WorldWideScience

Sample records for video image sequence

  1. Real-time UAV trajectory generation using feature points matching between video image sequences

    Science.gov (United States)

    Byun, Younggi; Song, Jeongheon; Han, Dongyeob

    2017-09-01

    Unmanned aerial vehicles (UAVs), equipped with navigation systems and video capability, are currently being deployed for intelligence, reconnaissance and surveillance mission. In this paper, we present a systematic approach for the generation of UAV trajectory using a video image matching system based on SURF (Speeded up Robust Feature) and Preemptive RANSAC (Random Sample Consensus). Video image matching to find matching points is one of the most important steps for the accurate generation of UAV trajectory (sequence of poses in 3D space). We used the SURF algorithm to find the matching points between video image sequences, and removed mismatching by using the Preemptive RANSAC which divides all matching points to outliers and inliers. The inliers are only used to determine the epipolar geometry for estimating the relative pose (rotation and translation) between image sequences. Experimental results from simulated video image sequences showed that our approach has a good potential to be applied to the automatic geo-localization of the UAVs system

  2. Computer Vision Tools for Finding Images and Video Sequences.

    Science.gov (United States)

    Forsyth, D. A.

    1999-01-01

    Computer vision offers a variety of techniques for searching for pictures in large collections of images. Appearance methods compare images based on the overall content of the image using certain criteria. Finding methods concentrate on matching subparts of images, defined in a variety of ways, in hope of finding particular objects. These ideas…

  3. On-board processing of video image sequences

    DEFF Research Database (Denmark)

    Andersen, Jakob Dahl; Chanrion, Olivier Arnaud; Forchhammer, Søren

    2008-01-01

    The ldquoatmosphere-space interactions monitorrdquo (ASIM) is a payload to be mounted on one of the external platforms of the Columbus module of the International Space Station (ISS). The instruments include six video cameras, six photometers and one X-ray detector. The main scientific objective...... of the mission is to study transient luminous events (TLE) above severe thunderstorms: the sprites, jets and elves. Other atmospheric phenomena are also studied including aurora, gravity waves and meteors. As part of the ASIM Phase B study, on-board processing of data from the cameras is being developed...

  4. Determination of exterior parameters for video image sequences from helicopter by block adjustment with combined vertical and oblique images

    Science.gov (United States)

    Zhang, Jianqing; Zhang, Yong; Zhang, Zuxun

    2003-09-01

    Determination of image exterior parameters is a key aspect for the realization of automatic texture mapping of buildings in the reconstruction of real 3D city models. This paper reports about an application of automatic aerial triangulation on a block with three video image sequences, one vertical image sequence to buildings' roofs and two oblique image sequences to buildings' walls. A new process procedure is developed in order to auto matching homologous points between images in oblique and vertical images. Two strategies are tested. One is treating three strips as independent blocks and executing strip block adjustment respectively, the other is creating a block with three strips, using the new image matching procedure to extract large number of tie points and executing block adjustment. The block adjustment results of these two strategies are also compared.

  5. Extracting a Good Quality Frontal Face Image from a Low-Resolution Video Sequence

    DEFF Research Database (Denmark)

    Nasrollahi, Kamal; Moeslund, Thomas B.

    2011-01-01

    Feeding low-resolution and low-quality images, from inexpensive surveillance cameras, to systems like, e.g., face recognition, produces erroneous and unstable results. Therefore, there is a need for a mechanism to bridge the gap between on one hand low-resolution and low-quality images and on the......Feeding low-resolution and low-quality images, from inexpensive surveillance cameras, to systems like, e.g., face recognition, produces erroneous and unstable results. Therefore, there is a need for a mechanism to bridge the gap between on one hand low-resolution and low-quality images...... and on the other hand facial analysis systems. The proposed system in this paper deals with exactly this problem. Our approach is to apply a reconstruction-based super-resolution algorithm. Such an algorithm, however, has two main problems: first, it requires relatively similar images with not too much noise...

  6. A video annotation methodology for interactive video sequence generation

    NARCIS (Netherlands)

    C.A. Lindley; R.A. Earnshaw; J.A. Vince

    2001-01-01

    textabstractThe FRAMES project within the RDN CRC (Cooperative Research Centre for Research Data Networks) has developed an experimental environment for dynamic virtual video sequence synthesis from databases of video data. A major issue for the development of dynamic interactive video applications

  7. Color image and video enhancement

    CERN Document Server

    Lecca, Michela; Smolka, Bogdan

    2015-01-01

    This text covers state-of-the-art color image and video enhancement techniques. The book examines the multivariate nature of color image/video data as it pertains to contrast enhancement, color correction (equalization, harmonization, normalization, balancing, constancy, etc.), noise removal and smoothing. This book also discusses color and contrast enhancement in vision sensors and applications of image and video enhancement.   ·         Focuses on enhancement of color images/video ·         Addresses algorithms for enhancing color images and video ·         Presents coverage on super resolution, restoration, in painting, and colorization.

  8. Image sequence analysis

    CERN Document Server

    1981-01-01

    The processing of image sequences has a broad spectrum of important applica­ tions including target tracking, robot navigation, bandwidth compression of TV conferencing video signals, studying the motion of biological cells using microcinematography, cloud tracking, and highway traffic monitoring. Image sequence processing involves a large amount of data. However, because of the progress in computer, LSI, and VLSI technologies, we have now reached a stage when many useful processing tasks can be done in a reasonable amount of time. As a result, research and development activities in image sequence analysis have recently been growing at a rapid pace. An IEEE Computer Society Workshop on Computer Analysis of Time-Varying Imagery was held in Philadelphia, April 5-6, 1979. A related special issue of the IEEE Transactions on Pattern Anal­ ysis and Machine Intelligence was published in November 1980. The IEEE Com­ puter magazine has also published a special issue on the subject in 1981. The purpose of this book ...

  9. Modeling camera orientation and 3D structure from a sequence of images taken by a perambulating commercial video camera

    Science.gov (United States)

    M-Rouhani, Behrouz; Anderson, James A. D. W.

    1997-04-01

    In this paper we report the degree of reliability of image sequences taken by off-the-shelf TV cameras for modeling camera rotation and reconstructing 3D structure using computer vision techniques. This is done in spite of the fact that computer vision systems usually use imaging devices that are specifically designed for the human vision. Our scenario consists of a static scene and a mobile camera moving through the scene. The scene is any long axial building dominated by features along the three principal orientations and with at least one wall containing prominent repetitive planar features such as doors, windows bricks etc. The camera is an ordinary commercial camcorder moving along the axial axis of the scene and is allowed to rotate freely within the range +/- 10 degrees in all directions. This makes it possible that the camera be held by a walking unprofessional cameraman with normal gait, or to be mounted on a mobile robot. The system has been tested successfully on sequence of images of a variety of structured, but fairly cluttered scenes taken by different walking cameramen. The potential application areas of the system include medicine, robotics and photogrammetry.

  10. Adaptive deblocking and deringing of H.264/AVC video sequences

    DEFF Research Database (Denmark)

    Nadernejad, Ehsan; Burini, Nino; Forchhammer, Søren

    2013-01-01

    We present a method to reduce blocking and ringing artifacts in H.264/AVC video sequences. For deblocking, the proposed method uses a quality measure of a block based coded image to find filtering modes. Based on filtering modes, the images are segmented to three classes and a specific deblocking...... filter is applied to each class. Deringing is obtained by an adaptive bilateral filter; spatial and intensity spread parameters are selected adaptively using texture and edge mapping. The analysis of objective and subjective experimental results shows that the proposed algorithm is effective...... in deblocking and deringing low bit-rate H.264 video sequences....

  11. Video library for video imaging detection at intersection stop lines.

    Science.gov (United States)

    2010-04-01

    The objective of this activity was to record video that could be used for controlled : evaluation of video image vehicle detection system (VIVDS) products and software upgrades to : existing products based on a list of conditions that might be diffic...

  12. MAP Estimation of Chin and Cheek Contours in Video Sequences

    Directory of Open Access Journals (Sweden)

    Kampmann Markus

    2004-01-01

    Full Text Available An algorithm for the estimation of chin and cheek contours in video sequences is proposed. This algorithm exploits a priori knowledge about shape and position of chin and cheek contours in images. Exploiting knowledge about the shape, a parametric 2D model representing chin and cheek contours is introduced. Exploiting knowledge about the position, a MAP estimator is developed taking into account the observed luminance gradient as well as a priori probabilities of chin and cheek contours positions. The proposed algorithm was tested with head and shoulder video sequences (image resolution CIF. In nearly 70% of all investigated video frames, a subjectively error free estimation could be achieved. The 2D estimate error is measured as on average between 2.4 and .

  13. Detectors for scanning video imagers

    Science.gov (United States)

    Webb, Robert H.; Hughes, George W.

    1993-11-01

    In scanning video imagers, a single detector sees each pixel for only 100 ns, so the bandwidth of the detector needs to be about 10 MHz. How this fact influences the choice of detectors for scanning systems is described here. Some important parametric quantities obtained from manufacturer specifications are related and it is shown how to compare detectors when specified quantities differ.

  14. Temporal compressive imaging for video

    Science.gov (United States)

    Zhou, Qun; Zhang, Linxia; Ke, Jun

    2018-01-01

    In many situations, imagers are required to have higher imaging speed, such as gunpowder blasting analysis and observing high-speed biology phenomena. However, measuring high-speed video is a challenge to camera design, especially, in infrared spectrum. In this paper, we reconstruct a high-frame-rate video from compressive video measurements using temporal compressive imaging (TCI) with a temporal compression ratio T=8. This means that, 8 unique high-speed temporal frames will be obtained from a single compressive frame using a reconstruction algorithm. Equivalently, the video frame rates is increased by 8 times. Two methods, two-step iterative shrinkage/threshold (TwIST) algorithm and the Gaussian mixture model (GMM) method, are used for reconstruction. To reduce reconstruction time and memory usage, each frame of size 256×256 is divided into patches of size 8×8. The influence of different coded mask to reconstruction is discussed. The reconstruction qualities using TwIST and GMM are also compared.

  15. Multimedia image and video processing

    CERN Document Server

    Guan, Ling

    2012-01-01

    As multimedia applications have become part of contemporary daily life, numerous paradigm-shifting technologies in multimedia processing have emerged over the last decade. Substantially updated with 21 new chapters, Multimedia Image and Video Processing, Second Edition explores the most recent advances in multimedia research and applications. This edition presents a comprehensive treatment of multimedia information mining, security, systems, coding, search, hardware, and communications as well as multimodal information fusion and interaction. Clearly divided into seven parts, the book begins w

  16. New algorithm for iris recognition based on video sequences

    Science.gov (United States)

    Bourennane, Salah; Fossati, Caroline; Ketchantang, William

    2010-07-01

    Among existing biometrics, iris recognition systems are among the most accurate personal biometric identification systems. However, the acquisition of a workable iris image requires strict cooperation of the user; otherwise, the image will be rejected by a verification module because of its poor quality, inducing a high false reject rate (FRR). The FRR may also increase when iris localization fails or when the pupil is too dilated. To improve the existing methods, we propose to use video sequences acquired in real time by a camera. In order to keep the same computational load to identify the iris, we propose a new method to estimate the iris characteristics. First, we propose a new iris texture characterization based on Fourier-Mellin transform, which is less sensitive to pupil dilatations than previous methods. Then, we develop a new iris localization algorithm that is robust to variations of quality (partial occlusions due to eyelids and eyelashes, light reflects, etc.), and finally, we introduce a fast and new criterion of suitable image selection from an iris video sequence for an accurate recognition. The accuracy of each step of the algorithm in the whole proposed recognition process is tested and evaluated using our own iris video database and several public image databases, such as CASIA, UBIRIS, and BATH.

  17. Motion-compensated scan conversion of interlaced video sequences

    Science.gov (United States)

    Schultz, Richard R.; Stevenson, Robert L.

    1996-03-01

    When an interlaced image sequence is viewed at the rate of sixty frames per second, the human visual system interpolates the data so that the missing fields are not noticeable. However, if frames are viewed individually, interlacing artifacts are quite prominent. This paper addresses the problem of deinterlacing image sequences for the purposes of analyzing video stills and generating high-resolution hardcopy of individual frames. Multiple interlaced frames are temporally integrated to estimate a single progressively-scanned still image, with motion compensation used between frames. A video observation model is defined which incorporates temporal information via estimated interframe motion vectors. The resulting ill- posed inverse problem is regularized through Bayesian maximum a posteriori (MAP) estimation, utilizing a discontinuity-preserving prior model for the spatial data. Progressively- scanned estimates computed from interlaced image sequences are shown at several spatial interpolation factors, since the multiframe Bayesian scan conversion algorithm is capable of simultaneously deinterlacing the data and enhancing spatial resolution. Problems encountered in the estimation of motion vectors from interlaced frames are addressed.

  18. Digital image sequence processing, compression, and analysis

    CERN Document Server

    Reed, Todd R

    2004-01-01

    IntroductionTodd R. ReedCONTENT-BASED IMAGE SEQUENCE REPRESENTATIONPedro M. Q. Aguiar, Radu S. Jasinschi, José M. F. Moura, andCharnchai PluempitiwiriyawejTHE COMPUTATION OF MOTIONChristoph Stiller, Sören Kammel, Jan Horn, and Thao DangMOTION ANALYSIS AND DISPLACEMENT ESTIMATION IN THE FREQUENCY DOMAINLuca Lucchese and Guido Maria CortelazzoQUALITY OF SERVICE ASSESSMENT IN NEW GENERATION WIRELESS VIDEO COMMUNICATIONSGaetano GiuntaERROR CONCEALMENT IN DIGITAL VIDEOFrancesco G.B. De NataleIMAGE SEQUENCE RESTORATION: A WIDER PERSPECTIVEAnil KokaramVIDEO SUMMARIZATIONCuneyt M. Taskiran and Edward

  19. Spatio-temporal image inpainting for video applications

    Directory of Open Access Journals (Sweden)

    Voronin Viacheslav

    2017-01-01

    Full Text Available Video inpainting or completion is a vital video improvement technique used to repair or edit digital videos. This paper describes a framework for temporally consistent video completion. The proposed method allows to remove dynamic objects or restore missing or tainted regions presented in a video sequence by utilizing spatial and temporal information from neighboring scenes. Masking algorithm is used for detection of scratches or damaged portions in video frames. The algorithm iteratively performs the following operations: achieve frame; update the scene model; update positions of moving objects; replace parts of the frame occupied by the objects marked for remove by using a background model. In this paper, we extend an image inpainting algorithm based texture and structure reconstruction by incorporating an improved strategy for video. Our algorithm is able to deal with a variety of challenging situations which naturally arise in video inpainting, such as the correct reconstruction of dynamic textures, multiple moving objects and moving background. Experimental comparisons to state-of-the-art video completion methods demonstrate the effectiveness of the proposed approach. It is shown that the proposed spatio-temporal image inpainting method allows restoring a missing blocks and removing a text from the scenes on videos.

  20. Finding and Improving the Key-Frames of Long Video Sequences for Face Recognition

    DEFF Research Database (Denmark)

    Nasrollahi, Kamal; Moeslund, Thomas B.

    2010-01-01

    of such video sequences by any enhancement or even face recognition algorithm is demanding. Thus, there is a need for a mechanism to summarize the input video sequence to a set of key-frames and then applying an enhancement algorithm to this subset. This paper presents a system doing exactly this. The system......Face recognition systems are very sensitive to the quality and resolution of their input face images. This makes such systems unreliable when working with long surveillance video sequences without employing some selection and enhancement algorithms. On the other hand, processing all the frames...... uses face quality assessment to select the key-frames and a hybrid super-resolution to enhance the face image quality. The suggested system that employs a linear associator face recognizer to evaluate the enhanced results has been tested on real surveillance video sequences and the experimental results...

  1. Region segmentation along image sequence

    Energy Technology Data Exchange (ETDEWEB)

    Monchal, L.; Aubry, P.

    1995-12-31

    A method to extract regions in sequence of images is proposed. Regions are not matched from one image to the following one. The result of a region segmentation is used as an initialization to segment the following and image to track the region along the sequence. The image sequence is exploited as a spatio-temporal event. (authors). 12 refs., 8 figs.

  2. Enhanced Video Surveillance (EVS) with speckle imaging

    Energy Technology Data Exchange (ETDEWEB)

    Carrano, C J

    2004-01-13

    Enhanced Video Surveillance (EVS) with Speckle Imaging is a high-resolution imaging system that substantially improves resolution and contrast in images acquired over long distances. This technology will increase image resolution up to an order of magnitude or greater for video surveillance systems. The system's hardware components are all commercially available and consist of a telescope or large-aperture lens assembly, a high-performance digital camera, and a personal computer. The system's software, developed at LLNL, extends standard speckle-image-processing methods (used in the astronomical community) to solve the atmospheric blurring problem associated with imaging over medium to long distances (hundreds of meters to tens of kilometers) through horizontal or slant-path turbulence. This novel imaging technology will not only enhance national security but also will benefit law enforcement, security contractors, and any private or public entity that uses video surveillance to protect their assets.

  3. ALOGORITHMS FOR AUTOMATIC RUNWAY DETECTION ON VIDEO SEQUENCES

    Directory of Open Access Journals (Sweden)

    A. I. Logvin

    2015-01-01

    Full Text Available The article discusses algorithm for automatic runway detection on video sequences. The main stages of algorithm are represented. Some methods to increase reliability of recognition are described.

  4. Still image and video compression with MATLAB

    CERN Document Server

    Thyagarajan, K

    2010-01-01

    This book describes the principles of image and video compression techniques and introduces current and popular compression standards, such as the MPEG series. Derivations of relevant compression algorithms are developed in an easy-to-follow fashion. Numerous examples are provided in each chapter to illustrate the concepts. The book includes complementary software written in MATLAB SIMULINK to give readers hands-on experience in using and applying various video compression methods. Readers can enhance the software by including their own algorithms.

  5. A reduced-reference perceptual image and video quality metric based on edge preservation

    Science.gov (United States)

    Martini, Maria G.; Villarini, Barbara; Fiorucci, Federico

    2012-12-01

    In image and video compression and transmission, it is important to rely on an objective image/video quality metric which accurately represents the subjective quality of processed images and video sequences. In some scenarios, it is also important to evaluate the quality of the received video sequence with minimal reference to the transmitted one. For instance, for quality improvement of video transmission through closed-loop optimisation, the video quality measure can be evaluated at the receiver and provided as feedback information to the system controller. The original image/video sequence--prior to compression and transmission--is not usually available at the receiver side, and it is important to rely at the receiver side on an objective video quality metric that does not need reference or needs minimal reference to the original video sequence. The observation that the human eye is very sensitive to edge and contour information of an image underpins the proposal of our reduced reference (RR) quality metric, which compares edge information between the distorted and the original image. Results highlight that the metric correlates well with subjective observations, also in comparison with commonly used full-reference metrics and with a state-of-the-art RR metric.

  6. An Imaging And Graphics Workstation For Image Sequence Analysis

    Science.gov (United States)

    Mostafavi, Hassan

    1990-01-01

    This paper describes an application-specific engineering workstation designed and developed to analyze imagery sequences from a variety of sources. The system combines the software and hardware environment of the modern graphic-oriented workstations with the digital image acquisition, processing and display techniques. The objective is to achieve automation and high throughput for many data reduction tasks involving metric studies of image sequences. The applications of such an automated data reduction tool include analysis of the trajectory and attitude of aircraft, missile, stores and other flying objects in various flight regimes including launch and separation as well as regular flight maneuvers. The workstation can also be used in an on-line or off-line mode to study three-dimensional motion of aircraft models in simulated flight conditions such as wind tunnels. The system's key features are: 1) Acquisition and storage of image sequences by digitizing real-time video or frames from a film strip; 2) computer-controlled movie loop playback, slow motion and freeze frame display combined with digital image sharpening, noise reduction, contrast enhancement and interactive image magnification; 3) multiple leading edge tracking in addition to object centroids at up to 60 fields per second from both live input video or a stored image sequence; 4) automatic and manual field-of-view and spatial calibration; 5) image sequence data base generation and management, including the measurement data products; 6) off-line analysis software for trajectory plotting and statistical analysis; 7) model-based estimation and tracking of object attitude angles; and 8) interface to a variety of video players and film transport sub-systems.

  7. Gait Analysis by Multi Video Sequence Analysis

    DEFF Research Database (Denmark)

    Jensen, Karsten; Juhl, Jens

    2009-01-01

    The project presented in this article aims to develop software so that close-range photogrammetry with sufficient accuracy can be used to point out the most frequent foot mal positions and monitor the effect of the traditional treatment. The project is carried out as a cooperation between...... the Orthopaedic Surgery in Northern Jutland and the Laboratory for Geoinformatics, Aalborg University. The superior requirements on the system are that it shall be without heavy expenses, be easy to install and easy to operate. A first version of the system is designed to measure the navicula height...... and the calcaneus angle during gait. In the introductory phase of the project the task has been to select, purchase and draw up hardware, select and purchase software concerning video streaming and to develop special software concerning automated registration of the position of the foot during gait by Multi Video...

  8. Sub-band/transform compression of video sequences

    Science.gov (United States)

    Sauer, Ken; Bauer, Peter

    1992-01-01

    The progress on compression of video sequences is discussed. The overall goal of the research was the development of data compression algorithms for high-definition television (HDTV) sequences, but most of our research is general enough to be applicable to much more general problems. We have concentrated on coding algorithms based on both sub-band and transform approaches. Two very fundamental issues arise in designing a sub-band coder. First, the form of the signal decomposition must be chosen to yield band-pass images with characteristics favorable to efficient coding. A second basic consideration, whether coding is to be done in two or three dimensions, is the form of the coders to be applied to each sub-band. Computational simplicity is of essence. We review the first portion of the year, during which we improved and extended some of the previous grant period's results. The pyramid nonrectangular sub-band coder limited to intra-frame application is discussed. Perhaps the most critical component of the sub-band structure is the design of bandsplitting filters. We apply very simple recursive filters, which operate at alternating levels on rectangularly sampled, and quincunx sampled images. We will also cover the techniques we have studied for the coding of the resulting bandpass signals. We discuss adaptive three-dimensional coding which takes advantage of the detection algorithm developed last year. To this point, all the work on this project has been done without the benefit of motion compensation (MC). Motion compensation is included in many proposed codecs, but adds significant computational burden and hardware expense. We have sought to find a lower-cost alternative featuring a simple adaptation to motion in the form of the codec. In sequences of high spatial detail and zooming or panning, it appears that MC will likely be necessary for the proposed quality and bit rates.

  9. Content-based image and video compression

    Science.gov (United States)

    Du, Xun; Li, Honglin; Ahalt, Stanley C.

    2002-08-01

    The term Content-Based appears often in applications for which MPEG-7 is expected to play a significant role. MPEG-7 standardizes descriptors of multimedia content, and while compression is not the primary focus of MPEG-7, the descriptors defined by MPEG-7 can be used to reconstruct a rough representation of an original multimedia source. In contrast, current image and video compression standards such as JPEG and MPEG are not designed to encode at the very low bit-rates that could be accomplished with MPEG-7 using descriptors. In this paper we show that content-based mechanisms can be introduced into compression algorithms to improve the scalability and functionality of current compression methods such as JPEG and MPEG. This is the fundamental idea behind Content-Based Compression (CBC). Our definition of CBC is a compression method that effectively encodes a sufficient description of the content of an image or a video in order to ensure that the recipient is able to reconstruct the image or video to some degree of accuracy. The degree of accuracy can be, for example, the classification error rate of the encoded objects, since in MPEG-7 the classification error rate measures the performance of the content descriptors. We argue that the major difference between a content-based compression algorithm and conventional block-based or object-based compression algorithms is that content-based compression replaces the quantizer with a more sophisticated classifier, or with a quantizer which minimizes classification error. Compared to conventional image and video compression methods such as JPEG and MPEG, our results show that content-based compression is able to achieve more efficient image and video coding by suppressing the background while leaving the objects of interest nearly intact.

  10. Quality-Aware Estimation of Facial Landmarks in Video Sequences

    DEFF Research Database (Denmark)

    Haque, Mohammad Ahsanul; Nasrollahi, Kamal; Moeslund, Thomas B.

    2015-01-01

    Face alignment in video is a primitive step for facial image analysis. The accuracy of the alignment greatly depends on the quality of the face image in the video frames and low quality faces are proven to cause erroneous alignment. Thus, this paper proposes a system for quality aware face...... alignment by using a Supervised Decent Method (SDM) along with a motion based forward extrapolation method. The proposed system first extracts faces from video frames. Then, it employs a face quality assessment technique to measure the face quality. If the face quality is high, the proposed system uses SDM...... for facial landmark detection. If the face quality is low the proposed system corrects the facial landmarks that are detected by SDM. Depending upon the face velocity in consecutive video frames and face quality measure, two algorithms are proposed for correction of landmarks in low quality faces by using...

  11. Structural image and video understanding

    NARCIS (Netherlands)

    Lou, Z.

    2016-01-01

    In this thesis, we have discussed how to exploit the structures in several computer vision topics. The five chapters addressed five computer vision topics using the image structures. In chapter 2, we proposed a structural model to jointly predict the age, expression and gender of a face. By modeling

  12. Image and Video for Hearing Impaired People

    Directory of Open Access Journals (Sweden)

    Thomas Burger

    2008-04-01

    Full Text Available We present a global overview of image- and video-processing-based methods to help the communication of hearing impaired people. Two directions of communication have to be considered: from a hearing person to a hearing impaired person and vice versa. In this paper, firstly, we describe sign language (SL and the cued speech (CS language which are two different languages used by the deaf community. Secondly, we present existing tools which employ SL and CS video processing and recognition for the automatic communication between deaf people and hearing people. Thirdly, we present the existing tools for reverse communication, from hearing people to deaf people that involve SL and CS video synthesis.

  13. Image and Video for Hearing Impaired People

    Directory of Open Access Journals (Sweden)

    Aran Oya

    2007-01-01

    Full Text Available We present a global overview of image- and video-processing-based methods to help the communication of hearing impaired people. Two directions of communication have to be considered: from a hearing person to a hearing impaired person and vice versa. In this paper, firstly, we describe sign language (SL and the cued speech (CS language which are two different languages used by the deaf community. Secondly, we present existing tools which employ SL and CS video processing and recognition for the automatic communication between deaf people and hearing people. Thirdly, we present the existing tools for reverse communication, from hearing people to deaf people that involve SL and CS video synthesis.

  14. Binocular video ophthalmoscope for simultaneous recording of sequences of the human retina to compare dynamic parameters

    Science.gov (United States)

    Tornow, Ralf P.; Milczarek, Aleksandra; Odstrcilik, Jan; Kolar, Radim

    2017-07-01

    A parallel video ophthalmoscope was developed to acquire short video sequences (25 fps, 250 frames) of both eyes simultaneously with exact synchronization. Video sequences were registered off-line to compensate for eye movements. From registered video sequences dynamic parameters like cardiac cycle induced reflection changes and eye movements can be calculated and compared between eyes.

  15. GPM GROUND VALIDATION PRECIPITATION VIDEO IMAGER (PVI) GCPEX V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The GPM Ground Validation Precipitation Video Imager (PVI) GCPEx dataset collected precipitation particle images and drop size distribution data from November 2011...

  16. Tracking of Individuals in Very Long Video Sequences

    DEFF Research Database (Denmark)

    Fihl, Preben; Corlin, Rasmus; Park, Sangho

    2006-01-01

    In this paper we present an approach for automatically detecting and tracking humans in very long video sequences. The detection is based on background subtraction using a multi-mode Codeword method. We enhance this method both in terms of representation and in terms of automatically updating the...

  17. STUDY OF BLOCKING EFFECT ELIMINATION METHODS BY MEANS OF INTRAFRAME VIDEO SEQUENCE INTERPOLATION

    Directory of Open Access Journals (Sweden)

    I. S. Rubina

    2015-01-01

    Full Text Available The paper deals with image interpolation methods and their applicability to eliminate some of the artifacts related to both the dynamic properties of objects in video sequences and algorithms used in the order of encoding steps. The main drawback of existing methods is the high computational complexity, unacceptable in video processing. Interpolation of signal samples for blocking - effect elimination at the output of the convertion encoding is proposed as a part of the study. It was necessary to develop methods for improvement of compression ratio and quality of the reconstructed video data by blocking effect elimination on the borders of the segments by intraframe interpolating of video sequence segments. The main point of developed methods is an adaptive recursive algorithm application with adaptive-sized interpolation kernel both with and without the brightness gradient consideration at the boundaries of objects and video sequence blocks. Within theoretical part of the research, methods of information theory (RD-theory and data redundancy elimination, methods of pattern recognition and digital signal processing, as well as methods of probability theory are used. Within experimental part of the research, software implementation of compression algorithms with subsequent comparison of the implemented algorithms with the existing ones was carried out. Proposed methods were compared with the simple averaging algorithm and the adaptive algorithm of central counting interpolation. The advantage of the algorithm based on the adaptive kernel size selection interpolation is in compression ratio increasing by 30%, and the advantage of the modified algorithm based on the adaptive interpolation kernel size selection is in the compression ratio increasing by 35% in comparison with existing algorithms, interpolation and quality of the reconstructed video sequence improving by 3% compared to the one compressed without interpolation. The findings will be

  18. Fuzzy Logic-Based Scenario Recognition from Video Sequences

    Directory of Open Access Journals (Sweden)

    E. Elbaşi

    2013-10-01

    Full Text Available In recent years, video surveillance and monitoring have gained importance because of security and safety concerns. Banks, borders, airports, stores, and parking areas are the important application areas. There are two main parts in scenario recognition: Low level processing, including moving object detection and object tracking, and feature extraction. We have developed new features through this work which are RUD (relative upper density, RMD (relative middle density and RLD (relative lower density, and we have used other features such as aspect ratio, width, height, and color of the object. High level processing, including event start-end point detection, activity detection for each frame and scenario recognition for sequence of images. This part is the focus of our research, and different pattern recognition and classification methods are implemented and experimental results are analyzed. We looked into several methods of classification which are decision tree, frequency domain classification, neural network-based classification, Bayes classifier, and pattern recognition methods, which are control charts, and hidden Markov models. The control chart approach, which is a decision methodology, gives more promising results than other methodologies. Overlapping between events is one of the problems, hence we applied fuzzy logic technique to solve this problem. After using this method the total accuracy increased from 95.6 to 97.2.

  19. Practical image and video processing using MATLAB

    CERN Document Server

    Marques, Oge

    2011-01-01

    "The book provides a practical introduction to the most important topics in image and video processing using MATLAB (and its Image Processing Toolbox) as a tool to demonstrate the most important techniques and algorithms. The contents are presented in a clear, technically accurate, objective way, with just enough mathematical detail. Most of the chapters are supported by figures, examples, illustrative problems, MATLAB scripts, suggestions for further reading, bibliographical references, useful Web sites, and exercises and computer projects to extend the understanding of their contents"--

  20. Multimodal location estimation of videos and images

    CERN Document Server

    Friedland, Gerald

    2015-01-01

    This book presents an overview of the field of multimodal location estimation, i.e. using acoustic, visual, and/or textual cues to estimate the shown location of a video recording. The authors' sample research results in this field in a unified way integrating research work on this topic that focuses on different modalities, viewpoints, and applications. The book describes fundamental methods of acoustic, visual, textual, social graph, and metadata processing as well as multimodal integration methods used for location estimation. In addition, the text covers benchmark metrics and explores the limits of the technology based on a human baseline. ·         Discusses localization of multimedia data; ·         Examines fundamental methods of establishing location metadata for images and videos (other than GPS tagging); ·         Covers Data-Driven as well as Semantic Location Estimation.

  1. Survey on attacks in image and video watermarking

    Science.gov (United States)

    Vassaux, Boris; Nguyen, Philippe; Baudry, Severine; Bas, Patrick; Chassery, Jean-Marc

    2002-11-01

    Watermarking techniques have been considerably improved for the last past years, aiming at being always more resistant to attacks. In fact, if the main goal of watermarking at the beginning was to secure digital data (audio, image and video), numerous attacks are still now able to cast doubts on the owner's authenticity ; we can distinguish three different groups of attacks : these one which consist to remove the watermark, these one which aim at impairing the data sufficiently to falsify the detection, and finally these one which try to alter the detection process so that another person becomes the apparent owner of the data. By considering the growing development of always more efficient attacks, this paper firstly presents a recent and exhaustive review of attacks in image and video watermarking. In a second part, the consequences of still image watermarking attacks on video sequences will be outlined and a particular attention will be given to the recently created benchmarks : Stirmark, the benchmark proposed by the University of Geneva Vision Group, this one proposed by the Department of Informatics of the University of Thessaloniki and finally we will speak of the current work of the European Project Certimark ; we will present a comparison of these various benchmarks and show how difficult it is to develop a self-sufficient benchmark, especially because of the complexity of intentional attacks.

  2. Hardware implementation of machine vision systems: image and video processing

    Science.gov (United States)

    Botella, Guillermo; García, Carlos; Meyer-Bäse, Uwe

    2013-12-01

    This contribution focuses on different topics covered by the special issue titled `Hardware Implementation of Machine vision Systems' including FPGAs, GPUS, embedded systems, multicore implementations for image analysis such as edge detection, segmentation, pattern recognition and object recognition/interpretation, image enhancement/restoration, image/video compression, image similarity and retrieval, satellite image processing, medical image processing, motion estimation, neuromorphic and bioinspired vision systems, video processing, image formation and physics based vision, 3D processing/coding, scene understanding, and multimedia.

  3. A novel visual saliency detection method for infrared video sequences

    Science.gov (United States)

    Wang, Xin; Zhang, Yuzhen; Ning, Chen

    2017-12-01

    Infrared video applications such as target detection and recognition, moving target tracking, and so forth can benefit a lot from visual saliency detection, which is essentially a method to automatically localize the ;important; content in videos. In this paper, a novel visual saliency detection method for infrared video sequences is proposed. Specifically, for infrared video saliency detection, both the spatial saliency and temporal saliency are considered. For spatial saliency, we adopt a mutual consistency-guided spatial cues combination-based method to capture the regions with obvious luminance contrast and contour features. For temporal saliency, a multi-frame symmetric difference approach is proposed to discriminate salient moving regions of interest from background motions. Then, the spatial saliency and temporal saliency are combined to compute the spatiotemporal saliency using an adaptive fusion strategy. Besides, to highlight the spatiotemporal salient regions uniformly, a multi-scale fusion approach is embedded into the spatiotemporal saliency model. Finally, a Gestalt theory-inspired optimization algorithm is designed to further improve the reliability of the final saliency map. Experimental results demonstrate that our method outperforms many state-of-the-art saliency detection approaches for infrared videos under various backgrounds.

  4. Dynamic Image Stitching for Panoramic Video

    Directory of Open Access Journals (Sweden)

    Jen-Yu Shieh

    2014-10-01

    Full Text Available The design of this paper is based on the Dynamic image titching for panoramic video. By utilizing OpenCV visual function data library and SIFT algorithm as the basis for presentation, this article brings forward Gaussian second differenced MoG which is processed basing on DoG Gaussian Difference Map to reduce order in synthesizing dynamic images and simplify the algorithm of the Gaussian pyramid structure. MSIFT matches with overlapping segmentation method to simplify the scope of feature extraction in order to enhance speed. And through this method traditional image synthesis can be improved without having to take lots of time in calculation and being limited by space and angle. This research uses four normal Webcams and two IPCAM coupled with several-wide angle lenses. By using wide-angle lenses to monitor over a wide range of an area and then by using image stitching panoramic effect is achieved. In terms of overall image application and control interface, Microsoft Visual Studio C# is adopted to a construct software interface. On a personal computer with 2.4-GHz CPU and 2-GB RAM and with the cameras fixed to it, the execution speed is three images per second, which reduces calculation time of the traditional algorithm.

  5. Does Instructor's Image Size in Video Lectures Affect Learning Outcomes?

    Science.gov (United States)

    Pi, Z.; Hong, J.; Yang, J.

    2017-01-01

    One of the most commonly used forms of video lectures is a combination of an instructor's image and accompanying lecture slides as a picture-in-picture. As the image size of the instructor varies significantly across video lectures, and so do the learning outcomes associated with this technology, the influence of the instructor's image size should…

  6. Multimodal interaction in image and video applications

    CERN Document Server

    Sappa, Angel D

    2013-01-01

    Traditional Pattern Recognition (PR) and Computer Vision (CV) technologies have mainly focused on full automation, even though full automation often proves elusive or unnatural in many applications, where the technology is expected to assist rather than replace the human agents. However, not all the problems can be automatically solved being the human interaction the only way to tackle those applications. Recently, multimodal human interaction has become an important field of increasing interest in the research community. Advanced man-machine interfaces with high cognitive capabilities are a hot research topic that aims at solving challenging problems in image and video applications. Actually, the idea of computer interactive systems was already proposed on the early stages of computer science. Nowadays, the ubiquity of image sensors together with the ever-increasing computing performance has open new and challenging opportunities for research in multimodal human interaction. This book aims to show how existi...

  7. Video Vortex reader II: moving images beyond YouTube

    NARCIS (Netherlands)

    Lovink, G.; Somers Miles, R.

    2011-01-01

    Video Vortex Reader II is the Institute of Network Cultures' second collection of texts that critically explore the rapidly changing landscape of online video and its use. With the success of YouTube ('2 billion views per day') and the rise of other online video sharing platforms, the moving image

  8. Image and video compression fundamentals, techniques, and applications

    CERN Document Server

    Joshi, Madhuri A; Dandawate, Yogesh H; Joshi, Kalyani R; Metkar, Shilpa P

    2014-01-01

    Image and video signals require large transmission bandwidth and storage, leading to high costs. The data must be compressed without a loss or with a small loss of quality. Thus, efficient image and video compression algorithms play a significant role in the storage and transmission of data.Image and Video Compression: Fundamentals, Techniques, and Applications explains the major techniques for image and video compression and demonstrates their practical implementation using MATLAB® programs. Designed for students, researchers, and practicing engineers, the book presents both basic principles

  9. Despeckle filtering for ultrasound imaging and video II selected applications

    CERN Document Server

    Loizou, Christos P

    2015-01-01

    In ultrasound imaging and video visual perception is hindered by speckle multiplicative noise that degrades the quality. Noise reduction is therefore essential for improving the visual observation quality or as a pre-processing step for further automated analysis, such as image/video segmentation, texture analysis and encoding in ultrasound imaging and video. The goal of the first book (book 1 of 2 books) was to introduce the problem of speckle in ultrasound image and video as well as the theoretical background, algorithmic steps, and the MatlabTM for the following group of despeckle filters:

  10. Image sequence analysis workstation for multipoint motion analysis

    Science.gov (United States)

    Mostafavi, Hassan

    1990-08-01

    This paper describes an application-specific engineering workstation designed and developed to analyze motion of objects from video sequences. The system combines the software and hardware environment of a modem graphic-oriented workstation with the digital image acquisition, processing and display techniques. In addition to automation and Increase In throughput of data reduction tasks, the objective of the system Is to provide less invasive methods of measurement by offering the ability to track objects that are more complex than reflective markers. Grey level Image processing and spatial/temporal adaptation of the processing parameters is used for location and tracking of more complex features of objects under uncontrolled lighting and background conditions. The applications of such an automated and noninvasive measurement tool include analysis of the trajectory and attitude of rigid bodies such as human limbs, robots, aircraft in flight, etc. The system's key features are: 1) Acquisition and storage of Image sequences by digitizing and storing real-time video; 2) computer-controlled movie loop playback, freeze frame display, and digital Image enhancement; 3) multiple leading edge tracking in addition to object centroids at up to 60 fields per second from both live input video or a stored Image sequence; 4) model-based estimation and tracking of the six degrees of freedom of a rigid body: 5) field-of-view and spatial calibration: 6) Image sequence and measurement data base management; and 7) offline analysis software for trajectory plotting and statistical analysis.

  11. CONTEXT-BASED URBAN TERRAIN RECONSTRUCTION FROM IMAGES AND VIDEOS

    Directory of Open Access Journals (Sweden)

    D. Bulatov

    2012-07-01

    Full Text Available Detection of buildings and vegetation, and even more reconstruction of urban terrain from sequences of aerial images and videos is known to be a challenging task. It has been established that those methods that have as input a high-quality Digital Surface Model (DSM, are more straight-forward and produce more robust and reliable results than those image-based methods that require matching line segments or even whole regions. This motivated us to develop a new dense matching technique for DSM generation that is capable of simultaneous integration of multiple images in the reconstruction process. The DSMs generated by this new multi-image matching technique can be used for urban object extraction. In the first contribution of this paper, two examples of external sources of information added to the reconstruction pipeline will be shown. The GIS layers are used for recognition of streets and suppressing false alarms in the depth maps that were caused by moving vehicles while the near infrared channel is applied for separating vegetation from buildings. Three examples of data sets including both UAV-borne video sequences with a relatively high number of frames and high-resolution (10 cm ground sample distance data sets consisting of (few spatial-temporarily diverse images from large-format aerial frame cameras, will be presented. By an extensive quantitative evaluation of the Vaihingen block from the ISPRS benchmark on urban object detection, it will become clear that our procedure allows a straight-forward, efficient, and reliable instantiation of 3D city models.

  12. Semi-Supervised Image-to-Video Adaptation for Video Action Recognition.

    Science.gov (United States)

    Zhang, Jianguang; Han, Yahong; Tang, Jinhui; Hu, Qinghua; Jiang, Jianmin

    2017-04-01

    Human action recognition has been well explored in applications of computer vision. Many successful action recognition methods have shown that action knowledge can be effectively learned from motion videos or still images. For the same action, the appropriate action knowledge learned from different types of media, e.g., videos or images, may be related. However, less effort has been made to improve the performance of action recognition in videos by adapting the action knowledge conveyed from images to videos. Most of the existing video action recognition methods suffer from the problem of lacking sufficient labeled training videos. In such cases, over-fitting would be a potential problem and the performance of action recognition is restrained. In this paper, we propose an adaptation method to enhance action recognition in videos by adapting knowledge from images. The adapted knowledge is utilized to learn the correlated action semantics by exploring the common components of both labeled videos and images. Meanwhile, we extend the adaptation method to a semi-supervised framework which can leverage both labeled and unlabeled videos. Thus, the over-fitting can be alleviated and the performance of action recognition is improved. Experiments on public benchmark datasets and real-world datasets show that our method outperforms several other state-of-the-art action recognition methods.

  13. GPM GROUND VALIDATION PRECIPITATION VIDEO IMAGER (PVI) GCPEX V1

    Data.gov (United States)

    National Aeronautics and Space Administration — The Precipitation Video Imager (PVI) collected precipitation particle images and drop size distribution data during November 2011 through March 2012 as part of the...

  14. Recognizing surgeon's actions during suture operations from video sequences

    Science.gov (United States)

    Li, Ye; Ohya, Jun; Chiba, Toshio; Xu, Rong; Yamashita, Hiromasa

    2014-03-01

    Because of the shortage of nurses in the world, the realization of a robotic nurse that can support surgeries autonomously is very important. More specifically, the robotic nurse should be able to autonomously recognize different situations of surgeries so that the robotic nurse can pass necessary surgical tools to the medical doctors in a timely manner. This paper proposes and explores methods that can classify suture and tying actions during suture operations from the video sequence that observes the surgery scene that includes the surgeon's hands. First, the proposed method uses skin pixel detection and foreground extraction to detect the hand area. Then, interest points are randomly chosen from the hand area so that their 3D SIFT descriptors are computed. A word vocabulary is built by applying hierarchical K-means to these descriptors, and the words' frequency histogram, which corresponds to the feature space, is computed. Finally, to classify the actions, either SVM (Support Vector Machine), Nearest Neighbor rule (NN) for the feature space or a method that combines "sliding window" with NN is performed. We collect 53 suture videos and 53 tying videos to build the training set and to test the proposed method experimentally. It turns out that the NN gives higher than 90% accuracies, which are better recognition than SVM. Negative actions, which are different from either suture or tying action, are recognized with quite good accuracies, while "Sliding window" did not show significant improvements for suture and tying and cannot recognize negative actions.

  15. Image and video search engine for the World Wide Web

    Science.gov (United States)

    Smith, John R.; Chang, Shih-Fu

    1997-01-01

    We describe a visual information system prototype for searching for images and videos on the World-Wide Web. New visual information in the form of images, graphics, animations and videos is being published on the Web at an incredible rate. However, cataloging this visual data is beyond the capabilities of current text-based Web search engines. In this paper, we describe a complete system by which visual information on the Web is (1) collected by automated agents, (2) processed in both text and visual feature domains, (3) catalogued and (4) indexed for fast search and retrieval. We introduce an image and video search engine which utilizes both text-based navigation and content-based technology for searching visually through the catalogued images and videos. Finally, we provide an initial evaluation based upon the cataloging of over one half million images and videos collected from the Web.

  16. Heart rate measurement based on face video sequence

    Science.gov (United States)

    Xu, Fang; Zhou, Qin-Wu; Wu, Peng; Chen, Xing; Yang, Xiaofeng; Yan, Hong-jian

    2015-03-01

    This paper proposes a new non-contact heart rate measurement method based on photoplethysmography (PPG) theory. With this method we can measure heart rate remotely with a camera and ambient light. We collected video sequences of subjects, and detected remote PPG signals through video sequences. Remote PPG signals were analyzed with two methods, Blind Source Separation Technology (BSST) and Cross Spectral Power Technology (CSPT). BSST is a commonly used method, and CSPT is used for the first time in the study of remote PPG signals in this paper. Both of the methods can acquire heart rate, but compared with BSST, CSPT has clearer physical meaning, and the computational complexity of CSPT is lower than that of BSST. Our work shows that heart rates detected by CSPT method have good consistency with the heart rates measured by a finger clip oximeter. With good accuracy and low computational complexity, the CSPT method has a good prospect for the application in the field of home medical devices and mobile health devices.

  17. On the relationship between perceptual impact of source and channel distortions in video sequences

    DEFF Research Database (Denmark)

    Korhonen, Jari; Reiter, Ulrich; You, Junyong

    2010-01-01

    It is known that peak signal-to-noise ratio (PSNR) can be used for assessing the relative qualities of distorted video sequences meaningfully only if the compared sequences contain similar types of distortions. In this paper, we propose a model for rough assessment of the bias in PSNR results, when...... video sequences with both channel and source distortion are compared against video sequences with source distortion only. The proposed method can be used to compare the relative perceptual quality levels of video sequences with different distortion types more reliably than using plain PSNR....

  18. Eye-Movement Tracking Using Compressed Video Images

    Science.gov (United States)

    Mulligan, Jeffrey B.; Beutter, Brent R.; Hull, Cynthia H. (Technical Monitor)

    1994-01-01

    Infrared video cameras offer a simple noninvasive way to measure the position of the eyes using relatively inexpensive equipment. Several commercial systems are available which use special hardware to localize features in the image in real time, but the constraint of realtime performance limits the complexity of the applicable algorithms. In order to get better resolution and accuracy, we have used off-line processing to apply more sophisticated algorithms to the images. In this case, a major technical challenge is the real-time acquisition and storage of the video images. This has been solved using a strictly digital approach, exploiting the burgeoning field of hardware video compression. In this paper we describe the algorithms we have developed for tracking the movements of the eyes in video images, and present experimental results showing how the accuracy is affected by the degree of video compression.

  19. Dactyl Alphabet Gesture Recognition in a Video Sequence Using Microsoft Kinect

    Science.gov (United States)

    Artyukhin, S. G.; Mestetskiy, L. M.

    2015-05-01

    This paper presents an efficient framework for solving the problem of static gesture recognition based on data obtained from the web cameras and depth sensor Kinect (RGB-D - data). Each gesture given by a pair of images: color image and depth map. The database store gestures by it features description, genereated by frame for each gesture of the alphabet. Recognition algorithm takes as input a video sequence (a sequence of frames) for marking, put in correspondence with each frame sequence gesture from the database, or decide that there is no suitable gesture in the database. First, classification of the frame of the video sequence is done separately without interframe information. Then, a sequence of successful marked frames in equal gesture is grouped into a single static gesture. We propose a method combined segmentation of frame by depth map and RGB-image. The primary segmentation is based on the depth map. It gives information about the position and allows to get hands rough border. Then, based on the color image border is specified and performed analysis of the shape of the hand. Method of continuous skeleton is used to generate features. We propose a method of skeleton terminal branches, which gives the opportunity to determine the position of the fingers and wrist. Classification features for gesture is description of the position of the fingers relative to the wrist. The experiments were carried out with the developed algorithm on the example of the American Sign Language. American Sign Language gesture has several components, including the shape of the hand, its orientation in space and the type of movement. The accuracy of the proposed method is evaluated on the base of collected gestures consisting of 2700 frames.

  20. VICAR - VIDEO IMAGE COMMUNICATION AND RETRIEVAL

    Science.gov (United States)

    Wall, R. J.

    1994-01-01

    VICAR (Video Image Communication and Retrieval) is a general purpose image processing software system that has been under continuous development since the late 1960's. Originally intended for data from the NASA Jet Propulsion Laboratory's unmanned planetary spacecraft, VICAR is now used for a variety of other applications including biomedical image processing, cartography, earth resources, and geological exploration. The development of this newest version of VICAR emphasized a standardized, easily-understood user interface, a shield between the user and the host operating system, and a comprehensive array of image processing capabilities. Structurally, VICAR can be divided into roughly two parts; a suite of applications programs and an executive which serves as the interfaces between the applications, the operating system, and the user. There are several hundred applications programs ranging in function from interactive image editing, data compression/decompression, and map projection, to blemish, noise, and artifact removal, mosaic generation, and pattern recognition and location. An information management system designed specifically for handling image related data can merge image data with other types of data files. The user accesses these programs through the VICAR executive, which consists of a supervisor and a run-time library. From the viewpoint of the user and the applications programs, the executive is an environment that is independent of the operating system. VICAR does not replace the host computer's operating system; instead, it overlays the host resources. The core of the executive is the VICAR Supervisor, which is based on NASA Goddard Space Flight Center's Transportable Applications Executive (TAE). Various modifications and extensions have been made to optimize TAE for image processing applications, resulting in a user friendly environment. The rest of the executive consists of the VICAR Run-Time Library, which provides a set of subroutines (image

  1. Detection and Localization of Anomalous Motion in Video Sequences from Local Histograms of Labeled Affine Flows

    Directory of Open Access Journals (Sweden)

    Juan-Manuel Pérez-Rúa

    2017-05-01

    Full Text Available We propose an original method for detecting and localizing anomalous motion patterns in videos from a camera view-based motion representation perspective. Anomalous motion should be taken in a broad sense, i.e., unexpected, abnormal, singular, irregular, or unusual motion. Identifying distinctive dynamic information at any time point and at any image location in a sequence of images is a key requirement in many situations and applications. The proposed method relies on so-called labeled affine flows (LAF involving both affine velocity vectors and affine motion classes. At every pixel, a motion class is inferred from the affine motion model selected in a set of candidate models estimated over a collection of windows. Then, the image is subdivided in blocks where motion class histograms weighted by the affine motion vector magnitudes are computed. They are compared blockwise to histograms of normal behaviors with a dedicated distance. More specifically, we introduce the local outlier factor (LOF to detect anomalous blocks. LOF is a local flexible measure of the relative density of data points in a feature space, here the space of LAF histograms. By thresholding the LOF value, we can detect an anomalous motion pattern in any block at any time instant of the video sequence. The threshold value is automatically set in each block by means of statistical arguments. We report comparative experiments on several real video datasets, demonstrating that our method is highly competitive for the intricate task of detecting different types of anomalous motion in videos. Specifically, we obtain very competitive results on all the tested datasets: 99.2% AUC for UMN, 82.8% AUC for UCSD, and 95.73% accuracy for PETS 2009, at the frame level.

  2. Comparison of optical flow algorithms performance on flame image sequences

    Science.gov (United States)

    Tanaś, J.; Kotyra, A.

    2017-08-01

    Analyzing flame image sequences of co-combusting pulverized coal and biomass can be used to determine the state of this very complex process. Considering dynamic changes between successive frames of such video streams the optical flow algorithms could be applied for di-agnostic purposes. The paper discusses effectiveness and performance of two approaches (sparse and dense optical flow) applied for several video streams of co-combusting biomass and pulverized coal, recorded with different combustion settings with a high-speed camera at the laboratory stand.

  3. Adaptive sensing and optimal power allocation for wireless video sensors with sigma-delta imager.

    Science.gov (United States)

    Marijan, Malisa; Demirkol, Ilker; Maricić I, Danijel; Sharma, Gaurav; Ignjatovi, Zeljko

    2010-10-01

    We consider optimal power allocation for wireless video sensors (WVSs), including the image sensor subsystem in the system analysis. By assigning a power-rate-distortion (P-R-D) characteristic for the image sensor, we build a comprehensive P-R-D optimization framework for WVSs. For a WVS node operating under a power budget, we propose power allocation among the image sensor, compression, and transmission modules, in order to minimize the distortion of the video reconstructed at the receiver. To demonstrate the proposed optimization method, we establish a P-R-D model for an image sensor based upon a pixel level sigma-delta (Σ∆) image sensor design that allows investigation of the tradeoff between the bit depth of the captured images and spatio-temporal characteristics of the video sequence under the power constraint. The optimization results obtained in this setting confirm that including the image sensor in the system optimization procedure can improve the overall video quality under power constraint and prolong the lifetime of the WVSs. In particular, when the available power budget for a WVS node falls below a threshold, adaptive sensing becomes necessary to ensure that the node communicates useful information about the video content while meeting its power budget.

  4. Research on defogging technology of video image based on FPGA

    Science.gov (United States)

    Liu, Shuo; Piao, Yan

    2015-03-01

    As the effect of atmospheric particles scattering, the video image captured by outdoor surveillance system has low contrast and brightness, which directly affects the application value of the system. The traditional defogging technology is mostly studied by software for the defogging algorithms of the single frame image. Moreover, the algorithms have large computation and high time complexity. Then, the defogging technology of video image based on Digital Signal Processing (DSP) has the problem of complex peripheral circuit. It can't be realized in real-time processing, and it's hard to debug and upgrade. In this paper, with the improved dark channel prior algorithm, we propose a kind of defogging technology of video image based on Field Programmable Gate Array (FPGA). Compared to the traditional defogging methods, the video image with high resolution can be processed in real-time. Furthermore, the function modules of the system have been designed by hardware description language. At last, the results show that the defogging system based on FPGA can process the video image with minimum resolution of 640×480 in real-time. After defogging, the brightness and contrast of video image are improved effectively. Therefore, the defogging technology proposed in the paper has a great variety of applications including aviation, forest fire prevention, national security and other important surveillance.

  5. Tracking cells in Life Cell Imaging videos using topological alignments

    Directory of Open Access Journals (Sweden)

    Ersoy Ilker

    2009-07-01

    Full Text Available Abstract Background With the increasing availability of live cell imaging technology, tracking cells and other moving objects in live cell videos has become a major challenge for bioimage informatics. An inherent problem for most cell tracking algorithms is over- or under-segmentation of cells – many algorithms tend to recognize one cell as several cells or vice versa. Results We propose to approach this problem through so-called topological alignments, which we apply to address the problem of linking segmentations of two consecutive frames in the video sequence. Starting from the output of a conventional segmentation procedure, we align pairs of consecutive frames through assigning sets of segments in one frame to sets of segments in the next frame. We achieve this through finding maximum weighted solutions to a generalized "bipartite matching" between two hierarchies of segments, where we derive weights from relative overlap scores of convex hulls of sets of segments. For solving the matching task, we rely on an integer linear program. Conclusion Practical experiments demonstrate that the matching task can be solved efficiently in practice, and that our method is both effective and useful for tracking cells in data sets derived from a so-called Large Scale Digital Cell Analysis System (LSDCAS. Availability The source code of the implementation is available for download from http://www.picb.ac.cn/patterns/Software/topaln.

  6. An Efficient Solution for Hand Gesture Recognition from Video Sequence

    Directory of Open Access Journals (Sweden)

    PRODAN, R.-C.

    2012-08-01

    Full Text Available The paper describes a system of hand gesture recognition by image processing for human robot interaction. The recognition and interpretation of the hand postures acquired through a video camera allow the control of the robotic arm activity: motion - translation and rotation in 3D - and tightening/releasing the clamp. A gesture dictionary was defined and heuristic algorithms for recognition were developed and tested. The system can be used for academic and industrial purposes, especially for those activities where the movements of the robotic arm were not previously scheduled, for training the robot easier than using a remote control. Besides the gesture dictionary, the novelty of the paper consists in a new technique for detecting the relative positions of the fingers in order to recognize the various hand postures, and in the achievement of a robust system for controlling robots by postures of the hands.

  7. Insertion of impairments in test video sequences for quality assessment based on psychovisual characteristics

    OpenAIRE

    López Velasco, Juan Pedro; Rodrigo Ferrán, Juan Antonio; Jiménez Bermejo, David; Menendez Garcia, Jose Manuel

    2014-01-01

    Assessing video quality is a complex task. While most pixel-based metrics do not present enough correlation between objective and subjective results, algorithms need to correspond to human perception when analyzing quality in a video sequence. For analyzing the perceived quality derived from concrete video artifacts in determined region of interest we present a novel methodology for generating test sequences which allow the analysis of impact of each individual distortion. Through results obt...

  8. PIZZARO: Forensic analysis and restoration of image and video data.

    Science.gov (United States)

    Kamenicky, Jan; Bartos, Michal; Flusser, Jan; Mahdian, Babak; Kotera, Jan; Novozamsky, Adam; Saic, Stanislav; Sroubek, Filip; Sorel, Michal; Zita, Ales; Zitova, Barbara; Sima, Zdenek; Svarc, Petr; Horinek, Jan

    2016-07-01

    This paper introduces a set of methods for image and video forensic analysis. They were designed to help to assess image and video credibility and origin and to restore and increase image quality by diminishing unwanted blur, noise, and other possible artifacts. The motivation came from the best practices used in the criminal investigation utilizing images and/or videos. The determination of the image source, the verification of the image content, and image restoration were identified as the most important issues of which automation can facilitate criminalists work. Novel theoretical results complemented with existing approaches (LCD re-capture detection and denoising) were implemented in the PIZZARO software tool, which consists of the image processing functionality as well as of reporting and archiving functions to ensure the repeatability of image analysis procedures and thus fulfills formal aspects of the image/video analysis work. Comparison of new proposed methods with the state of the art approaches is shown. Real use cases are presented, which illustrate the functionality of the developed methods and demonstrate their applicability in different situations. The use cases as well as the method design were solved in tight cooperation of scientists from the Institute of Criminalistics, National Drug Headquarters of the Criminal Police and Investigation Service of the Police of the Czech Republic, and image processing experts from the Czech Academy of Sciences. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  9. Method and apparatus for reading meters from a video image

    Science.gov (United States)

    Lewis, Trevor J.; Ferguson, Jeffrey J.

    1997-01-01

    A method and system to enable acquisition of data about an environment from one or more meters using video images. One or more meters are imaged by a video camera and the video signal is digitized. Then, each region of the digital image which corresponds to the indicator of the meter is calibrated and the video signal is analyzed to determine the value indicated by each meter indicator. Finally, from the value indicated by each meter indicator in the calibrated region, a meter reading is generated. The method and system offer the advantages of automatic data collection in a relatively non-intrusive manner without making any complicated or expensive electronic connections, and without requiring intensive manpower.

  10. Communicating pictures a course in image and video coding

    CERN Document Server

    Bull, David R

    2014-01-01

    Communicating Pictures starts with a unique historical perspective of the role of images in communications and then builds on this to explain the applications and requirements of a modern video coding system. It draws on the author's extensive academic and professional experience of signal processing and video coding to deliver a text that is algorithmically rigorous, yet accessible, relevant to modern standards, and practical. It offers a thorough grounding in visual perception, and demonstrates how modern image and video compression methods can be designed in order to meet the rate-quality performance levels demanded by today's applications, networks and users. With this book you will learn: Practical issues when implementing a codec, such as picture boundary extension and complexity reduction, with particular emphasis on efficient algorithms for transforms, motion estimators and error resilience Conflicts between conventional video compression, based on variable length coding and spatiotemporal prediction,...

  11. Chroma Subsampling Influence on the Perceived Video Quality for Compressed Sequences in High Resolutions

    Directory of Open Access Journals (Sweden)

    Miroslav Uhrina

    2017-01-01

    Full Text Available This paper deals with the influence of chroma subsampling on perceived video quality measured by subjective metrics. The evaluation was done for two most used video codecs H.264/AVC and H.265/HEVC. Eight types of video sequences with Full HD and Ultra HD resolutions depending on content were tested. The experimental results showed that observers did not see the difference between unsubsampled and subsampled sequences, so using subsampled videos is preferable even 50 % of the amount of data can be saved. Also, the minimum bitrates to achieve the good and fair quality by each codec and resolution were determined.

  12. Spatial-temporal forensic analysis of mass casualty incidents using video sequences.

    Science.gov (United States)

    Hao Dong; Juechen Yin; Schafer, James; Ganz, Aura

    2016-08-01

    In this paper we introduce DIORAMA based forensic analysis of mass casualty incidents (MCI) using video sequences. The video sequences captured on site are automatically annotated by metadata, which includes the capture time and the camera location and viewing direction. Using a visual interface the MCI investigators can easily understand the availability of video clips in specific areas of interest, and efficiently review them. The video-based forensic analysis system will enable the MCI investigators to better understand the rescue operations and subsequently improve training procedures.

  13. Compression of mixed video and graphics images for TV systems

    Science.gov (United States)

    van der Schaar-Mitrea, Mihaela; de With, Peter H. N.

    1998-01-01

    The diversity in TV images has augmented with the increased application of computer graphics. In this paper we study z coding system that supports both the lossless coding of such graphics data and regular lossy video compression. The lossless coding techniques are based on runlength and arithmetical coding. For video compression, we introduce a simple block predictive coding technique featuring individual pixel access, so that it enables a gradual shift from lossless coding of graphics to the lossy coding of video. An overall bit rate control completes the system. Computer simulations show a very high quality with a compression factor between 2-3.

  14. Summarization of Surveillance Video Sequences Using Face Quality Assessment

    DEFF Research Database (Denmark)

    Nasrollahi, Kamal; Moeslund, Thomas B.; Rahmati, Mohammad

    2011-01-01

    Constant working surveillance cameras in public places, such as airports and banks, produce huge amount of video data. Faces in such videos can be extracted in real time. However, most of these detected faces are either redundant or useless. Redundant information adds computational costs to facial...

  15. Applying deep learning to classify pornographic images and videos

    OpenAIRE

    Moustafa, Mohamed

    2015-01-01

    It is no secret that pornographic material is now a one-click-away from everyone, including children and minors. General social media networks are striving to isolate adult images and videos from normal ones. Intelligent image analysis methods can help to automatically detect and isolate questionable images in media. Unfortunately, these methods require vast experience to design the classifier including one or more of the popular computer vision feature descriptors. We propose to build a clas...

  16. Video image processing to create a speed sensor

    Science.gov (United States)

    1999-11-01

    Image processing has been applied to traffic analysis in recent years, with different goals. In the report, a new approach is presented for extracting vehicular speed information, given a sequence of real-time traffic images. We extract moving edges ...

  17. Mathematics from Still and Video Images.

    Science.gov (United States)

    Oldknow, Adrian

    2003-01-01

    Discusses simple tools for digitizing objects of interest from image files for treatment in other software such as graph plotters, data-handling software, or graphic calculators. Explores methods using MS Paint, Excel, DigitiseImage and TI Interactive (TII). (Author/NB)

  18. Recent advances in intelligent image search and video retrieval

    CERN Document Server

    2017-01-01

    This book initially reviews the major feature representation and extraction methods and effective learning and recognition approaches, which have broad applications in the context of intelligent image search and video retrieval. It subsequently presents novel methods, such as improved soft assignment coding, Inheritable Color Space (InCS) and the Generalized InCS framework, the sparse kernel manifold learner method, the efficient Support Vector Machine (eSVM), and the Scale-Invariant Feature Transform (SIFT) features in multiple color spaces. Lastly, the book presents clothing analysis for subject identification and retrieval, and performance evaluation methods of video analytics for traffic monitoring. Digital images and videos are proliferating at an amazing speed in the fields of science, engineering and technology, media and entertainment. With the huge accumulation of such data, keyword searches and manual annotation schemes may no longer be able to meet the practical demand for retrieving relevant conte...

  19. The advantages of using photographs and video images in ...

    African Journals Online (AJOL)

    Background: The purpose of this study was to evaluate the advantages of a telephone consultation with a specialist in paediatric surgery after taking photographs and video images by a general practitioner for the diagnosis of some diseases. Materials and Methods: This was a prospective study of the reliability of paediatric ...

  20. Low-noise video amplifiers for imaging CCD's

    Science.gov (United States)

    Scinicariello, F.

    1976-01-01

    Various techniques were developed which enable the CCD (charge coupled device) imaging array user to obtain optimum performance from the device. A CCD video channel was described, and detector-preamplifier interface requirements were examined. A noise model for the system was discussed at length and laboratory data presented and compared to predicted results.

  1. High-sensitivity hyperspectral imager for biomedical video diagnostic applications

    Science.gov (United States)

    Leitner, Raimund; Arnold, Thomas; De Biasio, Martin

    2010-04-01

    Video endoscopy allows physicians to visually inspect inner regions of the human body using a camera and only minimal invasive optical instruments. It has become an every-day routine in clinics all over the world. Recently a technological shift was done to increase the resolution from PAL/NTSC to HDTV. But, despite a vast literature on invivo and in-vitro experiments with multi-spectral point and imaging instruments that suggest that a wealth of information for diagnostic overlays is available in the visible spectrum, the technological evolution from colour to hyper-spectral video endoscopy is overdue. There were two approaches (NBI, OBI) that tried to increase the contrast for a better visualisation by using more than three wavelengths. But controversial discussions about the real benefit of a contrast enhancement alone, motivated a more comprehensive approach using the entire spectrum and pattern recognition algorithms. Up to now the hyper-spectral equipment was too slow to acquire a multi-spectral image stack at reasonable video rates rendering video endoscopy applications impossible. Recently, the availability of fast and versatile tunable filters with switching times below 50 microseconds made an instrumentation for hyper-spectral video endoscopes feasible. This paper describes a demonstrator for hyper-spectral video endoscopy and the results of clinical measurements using this demonstrator for measurements after otolaryngoscopic investigations and thorax surgeries. The application investigated here is the detection of dysplastic tissue, although hyper-spectral video endoscopy is of course not limited to cancer detection. Other applications are the detection of dysplastic tissue or polyps in the colon or the gastrointestinal tract.

  2. Image enhancement and moving target detection in IR image sequences

    NARCIS (Netherlands)

    Beck, W.

    1993-01-01

    Results are presented of noise reduction by motion compensated temporal filtering in a noisy IR image sequence and of moving target detection in an air-to-ground IR image sequence. In the case of motion compensated temporal filtering our approach consists of estimating the optical flow between

  3. Image-guided transorbital procedures with endoscopic video augmentation.

    Science.gov (United States)

    DeLisi, Michael P; Mawn, Louise A; Galloway, Robert L

    2014-09-01

    Surgical interventions to the orbital space behind the eyeball are limited to highly invasive procedures due to the confined nature of the region along with the presence of several intricate soft tissue structures. A minimally invasive approach to orbital surgery would enable several therapeutic options, particularly new treatment protocols for optic neuropathies such as glaucoma. The authors have developed an image-guided system for the purpose of navigating a thin flexible endoscope to a specified target region behind the eyeball. Navigation within the orbit is particularly challenging despite its small volume, as the presence of fat tissue occludes the endoscopic visual field while the surgeon must constantly be aware of optic nerve position. This research investigates the impact of endoscopic video augmentation to targeted image-guided navigation in a series of anthropomorphic phantom experiments. A group of 16 surgeons performed a target identification task within the orbits of four skull phantoms. The task consisted of identifying the correct target, indicated by the augmented video and the preoperative imaging frames, out of four possibilities. For each skull, one orbital intervention was performed with video augmentation, while the other was done with the standard image guidance technique, in random order. The authors measured a target identification accuracy of 95.3% and 85.9% for the augmented and standard cases, respectively, with statistically significant improvement in procedure time (Z=-2.044, p=0.041) and intraoperator mean procedure time (Z=2.456, p=0.014) when augmentation was used. Improvements in both target identification accuracy and interventional procedure time suggest that endoscopic video augmentation provides valuable additional orientation and trajectory information in an image-guided procedure. Utilization of video augmentation in transorbital interventions could further minimize complication risk and enhance surgeon comfort and

  4. Recognition of Bullet Holes Based on Video Image Analysis

    Science.gov (United States)

    Ruolin, Zhu; Jianbo, Liu; Yuan, Zhang; Xiaoyu, Wu

    2017-10-01

    The technology of computer vision is used in the training of military shooting. In order to overcome the limitation of the bullet holes recognition using Video Image Analysis that exists over-detection or leak-detection, this paper adopts the support vector machine algorithm and convolutional neural network to extract and recognize Bullet Holes in the digital video and compares their performance. It extracts HOG characteristics of bullet holes and train SVM classifier quickly, though the target is under outdoor environment. Experiments show that support vector machine algorithm used in this paper realize a fast and efficient extraction and recognition of bullet holes, improving the efficiency of shooting training.

  5. Guided filtering for solar image/video processing

    Science.gov (United States)

    Xu, Long; Yan, Yihua; Cheng, Jun

    2017-06-01

    A new image enhancement algorithm employing guided filtering is proposed in this work for enhancement of solar images and videos, so that users can easily figure out important fine structures imbedded in the recorded images/movies for solar observation. The proposed algorithm can efficiently remove image noises, including Gaussian and impulse noises. Meanwhile, it can further highlight fibrous structures on/beyond the solar disk. These fibrous structures can clearly demonstrate the progress of solar flare, prominence coronal mass emission, magnetic field, and so on. The experimental results prove that the proposed algorithm gives significant enhancement of visual quality of solar images beyond original input and several classical image enhancement algorithms, thus facilitating easier determi-nation of interesting solar burst activities from recorded images/movies.

  6. Thermal imagers: from ancient analog video output to state-of-the-art video streaming

    Science.gov (United States)

    Haan, Hubertus; Feuchter, Timo; Münzberg, Mario; Fritze, Jörg; Schlemmer, Harry

    2013-06-01

    The video output of thermal imagers stayed constant over almost two decades. When the famous Common Modules were employed a thermal image at first was presented to the observer in the eye piece only. In the early 1990s TV cameras were attached and the standard output was CCIR. In the civil camera market output standards changed to digital formats a decade ago with digital video streaming being nowadays state-of-the-art. The reasons why the output technique in the thermal world stayed unchanged over such a long time are: the very conservative view of the military community, long planning and turn-around times of programs and a slower growth of pixel number of TIs in comparison to consumer cameras. With megapixel detectors the CCIR output format is not sufficient any longer. The paper discusses the state-of-the-art compression and streaming solutions for TIs.

  7. Registration and recognition in images and videos

    CERN Document Server

    Battiato, Sebastiano; Farinella, Giovanni

    2014-01-01

    Computer vision is the science and technology of making machines that see. It is concerned with the theory, design and implementation of algorithms that can automatically process visual data to recognize objects, track and recover their shape and spatial layout. The International Computer Vision Summer School - ICVSS was established in 2007 to provide both an objective and clear overview and an in-depth analysis of the state-of-the-art  research in Computer Vision. The courses are delivered by world renowned experts in the field, from both academia and industry, and cover both theoretical and practical aspects of real Computer Vision problems.  The school is organized every year by University of Cambridge (Computer Vision and Robotics Group) and University of Catania (Image Processing Lab). Different topics are covered each year.This edited volume contains a selection of articles covering some of the talks and tutorials held during the last editions of the school. The chapters provide an in-depth overview o...

  8. Video-rate optical coherence tomography imaging with smart pixels

    Science.gov (United States)

    Beer, Stephan; Waldis, Severin; Seitz, Peter

    2003-10-01

    A novel concept for video-rate parallel acquisition of optical coherence tomography imaging is presented based on in-pixel demodulation. The main restrictions for parallel detection such as data rate, power consumption, circuit size and poor sensitivity are overcome with a smart pixel architecture incorporating an offset compensation circuit, a synchronous sampling stage, programmable time averaging and random pixel accessing, allowing envelope and phase detection in large 1D and 2D arrays.

  9. Fractal-based image sequence compression scheme

    Science.gov (United States)

    Li, Haibo; Novak, Mirek; Forchheimer, Robert

    1993-07-01

    The dominant image transformation used in the existing fractal coding schemes is the affine function. Although an affine transformation is easy to compute and understand, its linear approximation ability limits the employment of larger range blocks, that is, it limits further improvement in compression efficiency. We generalize the image transformation from the usual affine form to the more general quadratic form, and provide theoretical requirements for the generalized transformation to be contractive. Based on the self-transformation system (STS) model, an image sequence coding scheme--fractal-based image sequence coding--is proposed. In this coding scheme, our generalized transformation is used to model the self- transformation is used to model the self-transformation from the domain block to its range blocks. Experimental results on a real image sequence show that for the same size of blocks, the SNR can be improved by 10 dB, or, for the same SNR of the decoded image sequence, the compression ratio is raised twofold when the new generalized transformation is used to replace the usual affine transformation. In addition, due to the utilization of the STS model, the computational complexity is only linearly related to the size of the 3-D blocks. This provides for fast encoding and decoding.

  10. Integration of Video Images and CAD Wireframes for 3d Object Localization

    Science.gov (United States)

    Persad, R. A.; Armenakis, C.; Sohn, G.

    2012-07-01

    The tracking of moving objects from single images has received widespread attention in photogrammetric computer vision and considered to be at a state of maturity. This paper presents a model-driven solution for localizing moving objects detected from monocular, rotating and zooming video images in a 3D reference frame. To realize such a system, the recovery of 2D to 3D projection parameters is essential. Automatic estimation of these parameters is critical, particularly for pan-tilt-zoom (PTZ) surveillance cameras where parameters change spontaneously upon camera motion. In this work, an algorithm for automated parameter retrieval is proposed. This is achieved by matching linear features between incoming images from video sequences and simple geometric 3D CAD wireframe models of man-made structures. The feature matching schema uses a hypothesis-verify optimization framework referred to as LR-RANSAC. This novel method improves the computational efficiency of the matching process in comparison to the standard RANSAC robust estimator. To demonstrate the applicability and performance of the method, experiments have been performed on indoor and outdoor image sequences under varying conditions with lighting changes and occlusions. Reliability of the matching algorithm has been analyzed by comparing the automatically determined camera parameters with ground truth (GT). Dependability of the retrieved parameters for 3D localization has also been assessed by comparing the difference between 3D positions of moving image objects estimated using the LR-RANSAC-derived parameters and those computed using GT parameters.

  11. INTEGRATION OF VIDEO IMAGES AND CAD WIREFRAMES FOR 3D OBJECT LOCALIZATION

    Directory of Open Access Journals (Sweden)

    R. A. Persad

    2012-07-01

    Full Text Available The tracking of moving objects from single images has received widespread attention in photogrammetric computer vision and considered to be at a state of maturity. This paper presents a model-driven solution for localizing moving objects detected from monocular, rotating and zooming video images in a 3D reference frame. To realize such a system, the recovery of 2D to 3D projection parameters is essential. Automatic estimation of these parameters is critical, particularly for pan-tilt-zoom (PTZ surveillance cameras where parameters change spontaneously upon camera motion. In this work, an algorithm for automated parameter retrieval is proposed. This is achieved by matching linear features between incoming images from video sequences and simple geometric 3D CAD wireframe models of man-made structures. The feature matching schema uses a hypothesis-verify optimization framework referred to as LR-RANSAC. This novel method improves the computational efficiency of the matching process in comparison to the standard RANSAC robust estimator. To demonstrate the applicability and performance of the method, experiments have been performed on indoor and outdoor image sequences under varying conditions with lighting changes and occlusions. Reliability of the matching algorithm has been analyzed by comparing the automatically determined camera parameters with ground truth (GT. Dependability of the retrieved parameters for 3D localization has also been assessed by comparing the difference between 3D positions of moving image objects estimated using the LR-RANSAC-derived parameters and those computed using GT parameters.

  12. A Novel Face Segmentation Algorithm from a Video Sequence for Real-Time Face Recognition

    Directory of Open Access Journals (Sweden)

    Sudhaker Samuel RD

    2007-01-01

    Full Text Available The first step in an automatic face recognition system is to localize the face region in a cluttered background and carefully segment the face from each frame of a video sequence. In this paper, we propose a fast and efficient algorithm for segmenting a face suitable for recognition from a video sequence. The cluttered background is first subtracted from each frame, in the foreground regions, a coarse face region is found using skin colour. Then using a dynamic template matching approach the face is efficiently segmented. The proposed algorithm is fast and suitable for real-time video sequence. The algorithm is invariant to large scale and pose variation. The segmented face is then handed over to a recognition algorithm based on principal component analysis and linear discriminant analysis. The online face detection, segmentation, and recognition algorithms take an average of 0.06 second on a 3.2 GHz P4 machine.

  13. Image correlation method for DNA sequence alignment.

    Directory of Open Access Journals (Sweden)

    Millaray Curilem Saldías

    Full Text Available The complexity of searches and the volume of genomic data make sequence alignment one of bioinformatics most active research areas. New alignment approaches have incorporated digital signal processing techniques. Among these, correlation methods are highly sensitive. This paper proposes a novel sequence alignment method based on 2-dimensional images, where each nucleic acid base is represented as a fixed gray intensity pixel. Query and known database sequences are coded to their pixel representation and sequence alignment is handled as object recognition in a scene problem. Query and database become object and scene, respectively. An image correlation process is carried out in order to search for the best match between them. Given that this procedure can be implemented in an optical correlator, the correlation could eventually be accomplished at light speed. This paper shows an initial research stage where results were "digitally" obtained by simulating an optical correlation of DNA sequences represented as images. A total of 303 queries (variable lengths from 50 to 4500 base pairs and 100 scenes represented by 100 x 100 images each (in total, one million base pair database were considered for the image correlation analysis. The results showed that correlations reached very high sensitivity (99.01%, specificity (98.99% and outperformed BLAST when mutation numbers increased. However, digital correlation processes were hundred times slower than BLAST. We are currently starting an initiative to evaluate the correlation speed process of a real experimental optical correlator. By doing this, we expect to fully exploit optical correlation light properties. As the optical correlator works jointly with the computer, digital algorithms should also be optimized. The results presented in this paper are encouraging and support the study of image correlation methods on sequence alignment.

  14. Quality evaluation of edge detection in a road image sequences

    Directory of Open Access Journals (Sweden)

    Rodrigo B. de A. Gallis

    2004-12-01

    Full Text Available Terrestrial mobile mapping systems map interest features along roads such as poles, traffic signs, curb lines, garbage cans etc. The lab work, concerned to the object reconstruction, consists of transforming the video into still images on which homologous points and features of the road sequence are selected and measured. By means of photogrammetric intersection the object coordinates of these features and points are computed for 3D reconstruction. Using Canny algorithm for the automatic edge detection in a road image sequence the article initially focuses on the empiric determination of the required parameters (standard deviation s and high Ta and low Tb threshold. Then it presents the quality in terms of displacement of the automatically detected edges similar to those visually (manually selected straight features extracted by a human operator that takes them as correct, therefore, as reference for the automatic extraction comparison and the quality evaluation. The results of the tests are discussed and show that the quality of the automatic detection – measured by a quantity of rights and wrongs – vary accordingly to the empirically determined standard deviation and high and low thresholds and also to the image sequence environment (street or road.

  15. A Macro-Observation Scheme for Abnormal Event Detection in Daily-Life Video Sequences

    Directory of Open Access Journals (Sweden)

    Chiu Wei-Yao

    2010-01-01

    Full Text Available Abstract We propose a macro-observation scheme for abnormal event detection in daily life. The proposed macro-observation representation records the time-space energy of motions of all moving objects in a scene without segmenting individual object parts. The energy history of each pixel in the scene is instantly updated with exponential weights without explicitly specifying the duration of each activity. Since possible activities in daily life are numerous and distinct from each other and not all abnormal events can be foreseen, images from a video sequence that spans sufficient repetition of normal day-to-day activities are first randomly sampled. A constrained clustering model is proposed to partition the sampled images into groups. The new observed event that has distinct distance from any of the cluster centroids is then classified as an anomaly. The proposed method has been evaluated in daily work of a laboratory and BEHAVE benchmark dataset. The experimental results reveal that it can well detect abnormal events such as burglary and fighting as long as they last for a sufficient duration of time. The proposed method can be used as a support system for the scene that requires full time monitoring personnel.

  16. Coronary magnetic resonance vein imaging: imaging contrast, sequence, and timing.

    Science.gov (United States)

    Nezafat, Reza; Han, Yuchi; Peters, Dana C; Herzka, Daniel A; Wylie, John V; Goddu, Beth; Kissinger, Kraig K; Yeon, Susan B; Zimetbaum, Peter J; Manning, Warren J

    2007-12-01

    Recently, there has been increased interest in imaging the coronary vein anatomy to guide interventional cardiovascular procedures such as cardiac resynchronization therapy (CRT), a device therapy for congestive heart failure (CHF). With CRT the lateral wall of the left ventricle is electrically paced using a transvenous coronary sinus lead or surgically placed epicardial lead. Proper transvenous lead placement is facilitated by the knowledge of the coronary vein anatomy. Cardiovascular MR (CMR) has the potential to image the coronary veins. In this study we propose and test CMR techniques and protocols for imaging the coronary venous anatomy. Three aspects of design of imaging sequence were studied: magnetization preparation schemes (T(2) preparation and magnetization transfer), imaging sequences (gradient-echo (GRE) and steady-state free precession (SSFP)), and imaging time during the cardiac cycle. Numerical and in vivo studies both in healthy and CHF subjects were performed to optimize and demonstrate the utility of CMR for coronary vein imaging. Magnetization transfer was superior to T(2) preparation for contrast enhancement. Both GRE and SSFP were viable imaging sequences, although GRE provided more robust results with better contrast. Imaging during the end-systolic quiescent period was preferable as it coincided with the maximum size of the coronary veins. (c) 2007 Wiley-Liss, Inc.

  17. Feature Extraction in IR Images Via Synchronous Video Detection

    Science.gov (United States)

    Shepard, Steven M.; Sass, David T.

    1989-03-01

    IR video images acquired by scanning imaging radiometers are subject to several problems which make measurement of small temperature differences difficult. Among these problems are 1) aliasing, which occurs When events at frequencies higher than the video frame rate are observed, 2) limited temperature resolution imposed by the 3-bit digitization available in existing commercial systems, and 3) susceptibility to noise and background clutter. Bandwidth narrowing devices (e.g. lock-in amplifiers or boxcar averagers) are routinely used to achieve a high degree of signal to noise improvement for time-varying 1-dimensional signals. We will describe techniques which allow similar S/N improvement for 2-dimensional imagery acquired with an off the shelf scanning imaging radiometer system. These techniques are iplemented in near-real-time, utilizing a microcomputer and specially developed hardware and software . We will also discuss the application of the system to feature extraction in cluttered images, and to acquisition of events which vary faster than the frame rate.

  18. Realise : reconstruction of reality from image sequences

    NARCIS (Netherlands)

    Leymarie, F.; de la Fortelle, A.; Koenderink, Jan J.; Kappers, A. M L; Stavridi, M.; van Ginneken, B.; Muller, S.; Krake, S.; Faugeras, O.; Robert, L.; Gauclin, C.; Laveau, S.; Zeller, C.; Anon,

    1996-01-01

    REALISE has for principal goals to extract from sequences of images, acquired with a moving camera, information necessary for determining the 3D (CAD-like) structure of a real-life scene together with information about the radiometric signatures of surfaces bounding the extracted 3D objects (e.g.

  19. Video Enhancement and Dynamic Range Control of HDR Sequences for Automotive Applications

    Directory of Open Access Journals (Sweden)

    Giovanni Ramponi

    2007-01-01

    Full Text Available CMOS video cameras with high dynamic range (HDR output are particularly suitable for driving assistance applications, where lighting conditions can strongly vary, going from direct sunlight to dark areas in tunnels. However, common visualization devices can only handle a low dynamic range, and thus a dynamic range reduction is needed. Many algorithms have been proposed in the literature to reduce the dynamic range of still pictures. Anyway, extending the available methods to video is not straightforward, due to the peculiar nature of video data. We propose an algorithm for both reducing the dynamic range of video sequences and enhancing its appearance, thus improving visual quality and reducing temporal artifacts. We also provide an optimized version of our algorithm for a viable hardware implementation on an FPGA. The feasibility of this implementation is demonstrated by means of a case study.

  20. Automatic Representation and Segmentation of Video Sequences via a Novel Framework Based on the nD-EVM and Kohonen Networks

    Directory of Open Access Journals (Sweden)

    José-Yovany Luis-García

    2016-01-01

    Full Text Available Recently in the Computer Vision field, a subject of interest, at least in almost every video application based on scene content, is video segmentation. Some of these applications are indexing, surveillance, medical imaging, event analysis, and computer-guided surgery, for naming some of them. To achieve their goals, these applications need meaningful information about a video sequence, in order to understand the events in its corresponding scene. Therefore, we need semantic information which can be obtained from objects of interest that are present in the scene. In order to recognize objects we need to compute features which aid the finding of similarities and dissimilarities, among other characteristics. For this reason, one of the most important tasks for video and image processing is segmentation. The segmentation process consists in separating data into groups that share similar features. Based on this, in this work we propose a novel framework for video representation and segmentation. The main workflow of this framework is given by the processing of an input frame sequence in order to obtain, as output, a segmented version. For video representation we use the Extreme Vertices Model in the n-Dimensional Space while we use the Discrete Compactness descriptor as feature and Kohonen Self-Organizing Maps for segmentation purposes.

  1. Outward-looking circular motion analysis of large image sequences.

    Science.gov (United States)

    Jiang, Guang; Wei, Yichen; Quan, Long; Tsui, Hung-tat; Shum, Heung Yeung

    2005-02-01

    This paper presents a novel and simple method of analyzing the motion of a large image sequence captured by a calibrated outward-looking video camera moving on a circular trajectory for large-scale environment applications. Previous circular motion algorithms mainly focus on inward-looking turntable-like setups. They are not suitable for outward-looking motion where the conic trajectory of corresponding points degenerates to straight lines. The circular motion of a calibrated camera essentially has only one unknown rotation angle for each frame. The motion recovery for the entire sequence computes only one fundamental matrix of a pair of frames to extract the angular motion of the pair using Laguerre's formula and then propagates the computation of the unknown rotation angles to the other frames by tracking one point over at least three frames. Finally, a maximum-likelihood estimation is developed for the optimization of the whole sequence. Extensive experiments demonstrate the validity of the method and the feasibility of the application in image-based rendering.

  2. Sinusoidal Wave Estimation Using Photogrammetry and Short Video Sequences

    Directory of Open Access Journals (Sweden)

    Ewelina Rupnik

    2015-12-01

    Full Text Available The objective of the work is to model the shape of the sinusoidal shape of regular water waves generated in a laboratory flume. The waves are traveling in time and render a smooth surface, with no white caps or foam. Two methods are proposed, treating the water as a diffuse and specular surface, respectively. In either case, the water is presumed to take the shape of a traveling sine wave, reducing the task of the 3D reconstruction to resolve the wave parameters. The first conceived method performs the modeling part purely in 3D space. Having triangulated the points in a separate phase via bundle adjustment, a sine wave is fitted into the data in a least squares manner. The second method presents a more complete approach for the entire calculation workflow beginning in the image space. The water is perceived as a specular surface, and the traveling specularities are the only observations visible to the  cameras, observations that are notably single image. The depth ambiguity is removed given additional constraints encoded within the law of reflection and the modeled parametric surface. The observation and constraint equations compose a single system of equations that is solved with the method of least squares adjustment. The devised approaches are validated against the data coming from a capacitive level sensor and on physical targets floating on the surface. The outcomes agree to a high degree.

  3. Three-dimensional fuzzy filter in color video sequence denoising implemented on DSP

    Science.gov (United States)

    Ponomaryov, Volodymyr I.; Montenegro, Hector; Peralta-Fabi, Ricardo

    2013-02-01

    In this paper, we present a Fuzzy 3D filter for color video sequences to suppress impulsive noise. The difference between the designed algorithm in comparison with other state- of-the-art algorithms consists of employing the three RGB bands of the video sequence data and analyzing the fuzzy gradients values obtained in eight directions, finally processing two temporal neighboring frames together. The simulation results have confirmed sufficiently better performance of the novel 3D filter both in terms of objective metrics (PSNR, MAE, NCD, SSIM) as well as in subjective perception via human vision in the color sequences. An efficiency analysis of the designed and other promising filters have been performed on the DSP TMS320DM642 by Texas InstrumentsTM through MATLAB's SimulinkTM module, showing that the 3D filter can be used in real-time processing applications.

  4. JF-cut: a parallel graph cut approach for large-scale image and video.

    Science.gov (United States)

    Peng, Yi; Chen, Li; Ou-Yang, Fang-Xin; Chen, Wei; Yong, Jun-Hai

    2015-02-01

    Graph cut has proven to be an effective scheme to solve a wide variety of segmentation problems in vision and graphics community. The main limitation of conventional graph-cut implementations is that they can hardly handle large images or videos because of high computational complexity. Even though there are some parallelization solutions, they commonly suffer from the problems of low parallelism (on CPU) or low convergence speed (on GPU). In this paper, we present a novel graph-cut algorithm that leverages a parallelized jump flooding technique and an heuristic push-relabel scheme to enhance the graph-cut process, namely, back-and-forth relabel, convergence detection, and block-wise push-relabel. The entire process is parallelizable on GPU, and outperforms the existing GPU-based implementations in terms of global convergence, information propagation, and performance. We design an intuitive user interface for specifying interested regions in cases of occlusions when handling video sequences. Experiments on a variety of data sets, including images (up to 15 K × 10 K), videos (up to 2.5 K × 1.5 K × 50), and volumetric data, achieve high-quality results and a maximum 40-fold (139-fold) speedup over conventional GPU (CPU-)-based approaches.

  5. Enhancing Perceived Quality of Compressed Images and Video with Anisotropic Diffusion and Fuzzy Filtering

    DEFF Research Database (Denmark)

    Nadernejad, Ehsan; Korhonen, Jari; Forchhammer, Søren

    2013-01-01

    video sequences. For the video sequences, different filters are applied to luminance (Y) and chrominance (U,V) components. The performance of the proposed method has been compared against several other methods by using different objective quality metrics and a subjective comparison study. Both objective...

  6. Using underwater video imaging as an assessment tool for coastal condition

    Science.gov (United States)

    As part of an effort to monitor ecological conditions in nearshore habitats, from 2009-2012 underwater videos were captured at over 400 locations throughout the Laurentian Great Lakes. This study focuses on developing a video rating system and assessing video images. This ratin...

  7. Quantification of video-taped images in microcirculation research using inexpensive imaging software (Adobe Photoshop).

    Science.gov (United States)

    Brunner, J; Krummenauer, F; Lehr, H A

    2000-04-01

    Study end-points in microcirculation research are usually video-taped images rather than numeric computer print-outs. Analysis of these video-taped images for the quantification of microcirculatory parameters usually requires computer-based image analysis systems. Most software programs for image analysis are custom-made, expensive, and limited in their applicability to selected parameters and study end-points. We demonstrate herein that an inexpensive, commercially available computer software (Adobe Photoshop), run on a Macintosh G3 computer with inbuilt graphic capture board provides versatile, easy to use tools for the quantification of digitized video images. Using images obtained by intravital fluorescence microscopy from the pre- and postischemic muscle microcirculation in the skinfold chamber model in hamsters, Photoshop allows simple and rapid quantification (i) of microvessel diameters, (ii) of the functional capillary density and (iii) of postischemic leakage of FITC-labeled high molecular weight dextran from postcapillary venules. We present evidence of the technical accuracy of the software tools and of a high degree of interobserver reliability. Inexpensive commercially available imaging programs (i.e., Adobe Photoshop) provide versatile tools for image analysis with a wide range of potential applications in microcirculation research.

  8. Tracking of multiple points using color video image analyzer

    Science.gov (United States)

    Nennerfelt, Leif

    1990-08-01

    The Videomex-X is a new product intended for use in biomechanical measurement. It tracks up to six points at 60 frames per second using colored markers placed on the subject. The system can be used for applications such as gait analysis, studying facial movements, or tracking the pattern of movements of individuals in a group. The Videomex-X is comprised of a high speed color image analyzer, an RBG color video camera, an IBM AT compatible computer and motion analysis software. The markers are made from brightly colored plastic disks and each marker is a different color. Since the markers are unique, the problem of misidentification of markers does not occur. The Videomex-X performs realtime analysis so that the researcher can get immediate feedback on the subject's performance. High speed operation is possible because the system uses distributed processing. The image analyzer is a hardwired parallel image processor which identifies the markers within the video picture and computes their x-y locations. The image analyzer sends the x-y coordinates to the AT computer which performs additional analysis and presents the result. The x-y coordinate data acquired during the experiment may be streamed to the computer's hard disk. This allows the data to be re-analyzed repeatedly using different analysis criteria. The original Videomex-X tracked in two dimensions. However, a 3-D system has recently been completed. The algorithm used by the system to derive performance results from the x-y coordinates is contained in a separate ASCII file. These files can be modified by the operator to produce the required type of data reduction.

  9. Feature Extraction in Sequential Multimedia Images: with Applications in Satellite Images and On-line Videos

    Science.gov (United States)

    Liang, Yu-Li

    Multimedia data is increasingly important in scientific discovery and people's daily lives. Content of massive multimedia is often diverse and noisy, and motion between frames is sometimes crucial in analyzing those data. Among all, still images and videos are commonly used formats. Images are compact in size but do not contain motion information. Videos record motion but are sometimes too big to be analyzed. Sequential images, which are a set of continuous images with low frame rate, stand out because they are smaller than videos and still maintain motion information. This thesis investigates features in different types of noisy sequential images, and the proposed solutions that intelligently combined multiple features to successfully retrieve visual information from on-line videos and cloudy satellite images. The first task is detecting supraglacial lakes above ice sheet in sequential satellite images. The dynamics of supraglacial lakes on the Greenland ice sheet deeply affect glacier movement, which is directly related to sea level rise and global environment change. Detecting lakes above ice is suffering from diverse image qualities and unexpected clouds. A new method is proposed to efficiently extract prominent lake candidates with irregular shapes, heterogeneous backgrounds, and in cloudy images. The proposed system fully automatize the procedure that track lakes with high accuracy. We further cooperated with geoscientists to examine the tracked lakes and found new scientific findings. The second one is detecting obscene content in on-line video chat services, such as Chatroulette, that randomly match pairs of users in video chat sessions. A big problem encountered in such systems is the presence of flashers and obscene content. Because of various obscene content and unstable qualities of videos capture by home web-camera, detecting misbehaving users is a highly challenging task. We propose SafeVchat, which is the first solution that achieves satisfactory

  10. Persistent Target Tracking Using Likelihood Fusion in Wide-Area and Full Motion Video Sequences

    Science.gov (United States)

    2012-07-01

    problems associated with a moving platform including gimbal -based stabilization errors, relative motion where sensor and target are both moving, seams in...Image Processing, 2000, pp. 561–564. [46] A. Hafiane, K. Palaniappan, and G. Seetharaman, “ UAV -video registra- tion using block-based features,” in IEEE

  11. A video precipitation sensor for imaging and velocimetry of hydrometeors

    Science.gov (United States)

    Liu, X. C.; Gao, T. C.; Liu, L.

    2014-07-01

    A new method to determine the shape and fall velocity of hydrometeors by using a single CCD camera is proposed in this paper, and a prototype of a video precipitation sensor (VPS) is developed. The instrument consists of an optical unit (collimated light source with multi-mode fibre cluster), an imaging unit (planar array CCD sensor), an acquisition and control unit, and a data processing unit. The cylindrical space between the optical unit and imaging unit is sampling volume (300 mm × 40 mm × 30 mm). As the precipitation particles fall through the sampling volume, the CCD camera exposes twice in a single frame, which allows the double exposure of particles images to be obtained. The size and shape can be obtained by the images of particles; the fall velocity can be calculated by particle displacement in the double-exposure image and interval time; the drop size distribution and velocity distribution, precipitation intensity, and accumulated precipitation amount can be calculated by time integration. The innovation of VPS is that the shape, size, and velocity of precipitation particles can be measured by only one planar array CCD sensor, which can address the disadvantages of a linear scan CCD disdrometer and an impact disdrometer. Field measurements of rainfall demonstrate the VPS's capability to measure micro-physical properties of single particles and integral parameters of precipitation.

  12. Video dosimetry: evaluation of X-radiation dose by video fluoroscopic image; Videodosimetria: avaliacao da dose da radiacao X atraves da imagem videofluroscopica

    Energy Technology Data Exchange (ETDEWEB)

    Nova, Joao Luiz Leocadio da [Universidade Federal, Rio de Janeiro, RJ (Brazil). Centro de Ciencias da Saude. Nucleo de Tecnologia Educacional para a Saude; Lopes, Ricardo Tadeu [Universidade Federal, Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia. Lab. de Instrumentacao Nuclear

    1996-12-31

    A new methodology to evaluate the entrance surface dose on patients under radiodiagnosis is presented. A phantom is used in video fluoroscopic procedures in on line video signal system. The images are obtained from a Siemens Polymat 50 and are digitalized. The results show that the entrance surface dose can be obtained in real time from video imaging 3 refs., 2 figs., 2 tabs.

  13. Space debris detection in optical image sequences.

    Science.gov (United States)

    Xi, Jiangbo; Wen, Desheng; Ersoy, Okan K; Yi, Hongwei; Yao, Dalei; Song, Zongxi; Xi, Shaobo

    2016-10-01

    We present a high-accuracy, low false-alarm rate, and low computational-cost methodology for removing stars and noise and detecting space debris with low signal-to-noise ratio (SNR) in optical image sequences. First, time-index filtering and bright star intensity enhancement are implemented to remove stars and noise effectively. Then, a multistage quasi-hypothesis-testing method is proposed to detect the pieces of space debris with continuous and discontinuous trajectories. For this purpose, a time-index image is defined and generated. Experimental results show that the proposed method can detect space debris effectively without any false alarms. When the SNR is higher than or equal to 1.5, the detection probability can reach 100%, and when the SNR is as low as 1.3, 1.2, and 1, it can still achieve 99%, 97%, and 85% detection probabilities, respectively. Additionally, two large sets of image sequences are tested to show that the proposed method performs stably and effectively.

  14. Automatic flame tracking technique for atrium fire from video images

    Science.gov (United States)

    Li, Jin; Lu, Puyi; Fong, Naikong; Chow, Wanki; Wong, Lingtim; Xu, Dianguo

    2005-02-01

    Smoke control is one of the important aspects in atrium fire. For an efficient smoke control strategy, it is very important to identify the smoke and fire source in a very short period of time. However, traditional methods such as point type detectors are not effective for smoke and fire detection in large space such as atrium. Therefore, video smoke and fire detection systems are proposed. For the development of the system, automatic extraction and tracking of flame are two important problems needed to be solved. Based on entropy theory, region growing and Otsu method, a new automatic integrated algorithm, which is used to track flame from video images, is proposed in this paper. It can successfully identify flames from different environment, different background and in different form. The experimental results show that this integrated algorithm has stronger robustness and wider adaptability. In addition, because of the low computational demand of this algorithm, it is also possible to be used as part of a robust, real-time smoke and fire detection system.

  15. The Video Mesh: A Data Structure for Image-based Three-dimensional Video Editing

    OpenAIRE

    Chen, Jiawen; Paris, Sylvain; Wang, Jue; Matusik, Wojciech; Cohen, Michael; Durand, Fredo

    2011-01-01

    This paper introduces the video mesh, a data structure for representing video as 2.5D “paper cutouts.” The video mesh allows interactive editing of moving objects and modeling of depth, which enables 3D effects and post-exposure camera control. The video mesh sparsely encodes optical flow as well as depth, and handles occlusion using local layering and alpha mattes. Motion is described by a sparse set of points tracked over time. Each point also stores a depth value. The video mesh is a trian...

  16. Cryptanalysis of a spatiotemporal chaotic image/video cryptosystem

    Energy Technology Data Exchange (ETDEWEB)

    Rhouma, Rhouma [6' com laboratory, Ecole Nationale d' Ingenieurs de Tunis (ENIT) (Tunisia)], E-mail: rhoouma@yahoo.fr; Belghith, Safya [6' com laboratory, Ecole Nationale d' Ingenieurs de Tunis (ENIT) (Tunisia)

    2008-09-01

    This Letter proposes two different attacks on a recently proposed chaotic cryptosystem for images and videos in [S. Lian, Chaos Solitons Fractals (2007), (doi: 10.1016/j.chaos.2007.10.054)]. The cryptosystem under study displays weakness in the generation of the keystream. The encryption is made by generating a keystream mixed with blocks generated from the plaintext and the ciphertext in a CBC mode design. The so obtained keystream remains unchanged for every encryption procedure. Guessing the keystream leads to guessing the key. Two possible attacks are then able to break the whole cryptosystem based on this drawback in generating the keystream. We propose also to change the description of the cryptosystem to be robust against the described attacks by making it in a PCBC mode design.

  17. HIERARCHICAL ADAPTIVE ROOD PATTERN SEARCH FOR MOTION ESTIMATION AT VIDEO SEQUENCE ANALYSIS

    Directory of Open Access Journals (Sweden)

    V. T. Nguyen

    2016-05-01

    Full Text Available Subject of Research.The paper deals with the motion estimation algorithms for the analysis of video sequences in compression standards MPEG-4 Visual and H.264. Anew algorithm has been offered based on the analysis of the advantages and disadvantages of existing algorithms. Method. Thealgorithm is called hierarchical adaptive rood pattern search (Hierarchical ARPS, HARPS. This new algorithm includes the classic adaptive rood pattern search ARPS and hierarchical search MP (Hierarchical search or Mean pyramid. All motion estimation algorithms have been implemented using MATLAB package and tested with several video sequences. Main Results. The criteria for evaluating the algorithms were: speed, peak signal to noise ratio, mean square error and mean absolute deviation. The proposed method showed a much better performance at a comparable error and deviation. The peak signal to noise ratio in different video sequences shows better and worse results than characteristics of known algorithms so it requires further investigation. Practical Relevance. Application of this algorithm in MPEG-4 and H.264 codecs instead of the standard can significantly reduce compression time. This feature enables to recommend it in telecommunication systems for multimedia data storing, transmission and processing.

  18. Disparity estimation from monocular image sequence

    Science.gov (United States)

    Zhang, Qieshi; Kamata, Sei-ichiro

    2015-02-01

    This paper proposes a novel method for estimating disparity accurately. To achieve the ideal result, an optimal adjusting framework is proposed to address the noise, occlusions, and outliners. Different from the typical multi-view stereo (MVS) methods, the proposed approach not only use the color constraint, but also use the geometric constraint associating multiple frame from the image sequence. The result shows the disparity with a good visual quality that most of the noise is eliminated, the errors in occlusion area are suppressed and the details of scene objects are preserved.

  19. High-speed three-frame image recording system using colored flash units and low-cost video equipment

    Science.gov (United States)

    Racca, Roberto G.; Scotten, Larry N.

    1995-05-01

    This article describes a method that allows the digital recording of sequences of three black and white images at rates of several thousand frames per second using a system consisting of an ordinary CCD camcorder, three flash units with color filters, a PC-based frame grabber board and some additional electronics. The maximum framing rate is determined by the duration of the flashtube emission, and for common photographic flash units lasting about 20 microsecond(s) it can exceed 10,000 frames per second in actual use. The subject under study is strobe- illuminated using a red, a green and a blue flash unit controlled by a special sequencer, and the three images are captured by a color CCD camera on a single video field. Color is used as the distinguishing parameter that allows the overlaid exposures to be resolved. The video output for that particular field will contain three individual scenes, one for each primary color component, which potentially can be resolved with no crosstalk between them. The output is electronically decoded into the primary color channels, frame grabbed and stored into digital memory, yielding three time-resolved images of the subject. A synchronization pulse provided by the flash sequencer triggers the frame grabbing so that the correct video field is acquired. A scheme involving the use of videotape as intermediate storage allows the frame grabbing to be performed using a monochrome video digitizer. Ideally each flash- illuminated scene would be confined to one color channel, but in practice various factors, both optical and electronic, affect color separation. Correction equations have been derived that counteract these effects in the digitized images and minimize 'ghosting' between frames. Once the appropriate coefficients have been established through a calibration procedure that needs to be performed only once for a given configuration of the equipment, the correction process is carried out transparently in software every time a

  20. Digital Path Approach Despeckle Filter for Ultrasound Imaging and Video

    Directory of Open Access Journals (Sweden)

    Marek Szczepański

    2017-01-01

    Full Text Available We propose a novel filtering technique capable of reducing the multiplicative noise in ultrasound images that is an extension of the denoising algorithms based on the concept of digital paths. In this approach, the filter weights are calculated taking into account the similarity between pixel intensities that belongs to the local neighborhood of the processed pixel, which is called a path. The output of the filter is estimated as the weighted average of pixels connected by the paths. The way of creating paths is pivotal and determines the effectiveness and computational complexity of the proposed filtering design. Such procedure can be effective for different types of noise but fail in the presence of multiplicative noise. To increase the filtering efficiency for this type of disturbances, we introduce some improvements of the basic concept and new classes of similarity functions and finally extend our techniques to a spatiotemporal domain. The experimental results prove that the proposed algorithm provides the comparable results with the state-of-the-art techniques for multiplicative noise removal in ultrasound images and it can be applied for real-time image enhancement of video streams.

  1. 4DCAPTURE: a general purpose software package for capturing and analyzing two- and three-dimensional motion data acquired from video sequences

    Science.gov (United States)

    Walton, James S.; Hodgson, Peter; Hallamasek, Karen; Palmer, Jake

    2003-07-01

    4DVideo is creating a general purpose capability for capturing and analyzing kinematic data from video sequences in near real-time. The core element of this capability is a software package designed for the PC platform. The software ("4DCapture") is designed to capture and manipulate customized AVI files that can contain a variety of synchronized data streams -- including audio, video, centroid locations -- and signals acquired from more traditional sources (such as accelerometers and strain gauges.) The code includes simultaneous capture or playback of multiple video streams, and linear editing of the images (together with the ancilliary data embedded in the files). Corresponding landmarks seen from two or more views are matched automatically, and photogrammetric algorithms permit multiple landmarks to be tracked in two- and three-dimensions -- with or without lens calibrations. Trajectory data can be processed within the main application or they can be exported to a spreadsheet where they can be processed or passed along to a more sophisticated, stand-alone, data analysis application. Previous attempts to develop such applications for high-speed imaging have been limited in their scope, or by the complexity of the application itself. 4DVideo has devised a friendly ("FlowStack") user interface that assists the end-user to capture and treat image sequences in a natural progression. 4DCapture employs the AVI 2.0 standard and DirectX technology which effectively eliminates the file size limitations found in older applications. In early tests, 4DVideo has streamed three RS-170 video sources to disk for more than an hour without loss of data. At this time, the software can acquire video sequences in three ways: (1) directly, from up to three hard-wired cameras supplying RS-170 (monochrome) signals; (2) directly, from a single camera or video recorder supplying an NTSC (color) signal; and (3) by importing existing video streams in the AVI 1.0 or AVI 2.0 formats. The

  2. Composing with Images: A Study of High School Video Producers.

    Science.gov (United States)

    Reilly, Brian

    At Bell High School (Los Angeles, California), students have been using video cameras, computers and editing machines to create videos in a variety of forms and on a variety of topics; in this setting, video is the textual medium of expression. A study was conducted using participant-observation and interviewing over the course of one school year…

  3. Energy efficient image/video data transmission on commercial multi-core processors.

    Science.gov (United States)

    Lee, Sungju; Kim, Heegon; Chung, Yongwha; Park, Daihee

    2012-11-01

    In transmitting image/video data over Video Sensor Networks (VSNs), energy consumption must be minimized while maintaining high image/video quality. Although image/video compression is well known for its efficiency and usefulness in VSNs, the excessive costs associated with encoding computation and complexity still hinder its adoption for practical use. However, it is anticipated that high-performance handheld multi-core devices will be used as VSN processing nodes in the near future. In this paper, we propose a way to improve the energy efficiency of image and video compression with multi-core processors while maintaining the image/video quality. We improve the compression efficiency at the algorithmic level or derive the optimal parameters for the combination of a machine and compression based on the tradeoff between the energy consumption and the image/video quality. Based on experimental results, we confirm that the proposed approach can improve the energy efficiency of the straightforward approach by a factor of 2~5 without compromising image/video quality.

  4. Digital video image processing from dental operating microscope in endodontic treatment.

    Science.gov (United States)

    Suehara, Masataka; Nakagawa, Kan-Ichi; Aida, Natsuko; Ushikubo, Toshihiro; Morinaga, Kazuki

    2012-01-01

    Recently, optical microscopes have been used in endodontic treatment, as they offer advantages in terms of magnification, illumination, and documentation. Documentation is particularly important in presenting images to patients, and can take the form of both still images and motion video. Although high-quality still images can be obtained using a 35-mm film or CCD camera, the quality of still images produced by a video camera is significantly lower. The purpose of this study was to determine the potential of RegiStax in obtaining high-quality still images from a continuous video stream from an optical microscope. Video was captured continuously and sections with the highest luminosity chosen for frame alignment and stacking using the RegiStax program. The resulting stacked images were subjected to wavelet transformation. The results indicate that high-quality images with a large depth of field could be obtained using this method.

  5. Fall Detection for Elderly from Partially Observed Depth-Map Video Sequences Based on View-Invariant Human Activity Representation

    Directory of Open Access Journals (Sweden)

    Rami Alazrai

    2017-03-01

    Full Text Available This paper presents a new approach for fall detection from partially-observed depth-map video sequences. The proposed approach utilizes the 3D skeletal joint positions obtained from the Microsoft Kinect sensor to build a view-invariant descriptor for human activity representation, called the motion-pose geometric descriptor (MPGD. Furthermore, we have developed a histogram-based representation (HBR based on the MPGD to construct a length-independent representation of the observed video subsequences. Using the constructed HBR, we formulate the fall detection problem as a posterior-maximization problem in which the posteriori probability for each observed video subsequence is estimated using a multi-class SVM (support vector machine classifier. Then, we combine the computed posteriori probabilities from all of the observed subsequences to obtain an overall class posteriori probability of the entire partially-observed depth-map video sequence. To evaluate the performance of the proposed approach, we have utilized the Kinect sensor to record a dataset of depth-map video sequences that simulates four fall-related activities of elderly people, including: walking, sitting, falling form standing and falling from sitting. Then, using the collected dataset, we have developed three evaluation scenarios based on the number of unobserved video subsequences in the testing videos, including: fully-observed video sequence scenario, single unobserved video subsequence of random lengths scenarios and two unobserved video subsequences of random lengths scenarios. Experimental results show that the proposed approach achieved an average recognition accuracy of 93 . 6 % , 77 . 6 % and 65 . 1 % , in recognizing the activities during the first, second and third evaluation scenario, respectively. These results demonstrate the feasibility of the proposed approach to detect falls from partially-observed videos.

  6. Classification of video sequences into chosen generalized use classes of target size and lighting level.

    Science.gov (United States)

    Leszczuk, Mikołaj; Dudek, Łukasz; Witkowski, Marcin

    The VQiPS (Video Quality in Public Safety) Working Group, supported by the U.S. Department of Homeland Security, has been developing a user guide for public safety video applications. According to VQiPS, five parameters have particular importance influencing the ability to achieve a recognition task. They are: usage time-frame, discrimination level, target size, lighting level, and level of motion. These parameters form what are referred to as Generalized Use Classes (GUCs). The aim of our research was to develop algorithms that would automatically assist classification of input sequences into one of the GUCs. Target size and lighting level parameters were approached. The experiment described reveals the experts' ambiguity and hesitation during the manual target size determination process. However, the automatic methods developed for target size classification make it possible to determine GUC parameters with 70 % compliance to the end-users' opinion. Lighting levels of the entire sequence can be classified with an efficiency reaching 93 %. To make the algorithms available for use, a test application has been developed. It is able to process video files and display classification results, the user interface being very simple and requiring only minimal user interaction.

  7. Spatiotemporal Super-Resolution Reconstruction Based on Robust Optical Flow and Zernike Moment for Video Sequences

    Directory of Open Access Journals (Sweden)

    Meiyu Liang

    2013-01-01

    Full Text Available In order to improve the spatiotemporal resolution of the video sequences, a novel spatiotemporal super-resolution reconstruction model (STSR based on robust optical flow and Zernike moment is proposed in this paper, which integrates the spatial resolution reconstruction and temporal resolution reconstruction into a unified framework. The model does not rely on accurate estimation of subpixel motion and is robust to noise and rotation. Moreover, it can effectively overcome the problems of hole and block artifacts. First we propose an efficient robust optical flow motion estimation model based on motion details preserving, then we introduce the biweighted fusion strategy to implement the spatiotemporal motion compensation. Next, combining the self-adaptive region correlation judgment strategy, we construct a fast fuzzy registration scheme based on Zernike moment for better STSR with higher efficiency, and then the final video sequences with high spatiotemporal resolution can be obtained by fusion of the complementary and redundant information with nonlocal self-similarity between the adjacent video frames. Experimental results demonstrate that the proposed method outperforms the existing methods in terms of both subjective visual and objective quantitative evaluations.

  8. Surgical tool detection in cataract surgery videos through multi-image fusion inside a convolutional neural network.

    Science.gov (United States)

    Al Hajj, Hassan; Lamard, Mathieu; Charriere, Katia; Cochener, Beatrice; Quellec, Gwenole

    2017-07-01

    The automatic detection of surgical tools in surgery videos is a promising solution for surgical workflow analysis. It paves the way to various applications, including surgical workflow optimization, surgical skill evaluation and real-time warning generation. A solution based on convolutional neural networks (CNNs) is proposed in this paper. Unlike existing solutions, the proposed CNN does not analyze images independently. it analyzes sequences of consecutive images. Features extracted from each image by the CNN are fused inside the network using the optical flow. For improved performance, this multi-image fusion strategy is also applied while training the CNN. The proposed framework was evaluated in a dataset of 30 cataract surgery videos (6 hours of videos). Ten tool categories were defined by surgeons. The proposed system was able to detect each of these categories with a high area under the ROC curve (0.953 ≤ Az ≤ 0.987). The proposed detector, based on multi-image fusion, was significantly more sensitive and specific than a similar system analyzing images independently (p = 2.98 × 10(-6) and p = 2.07 × 10(-3), respectively).

  9. Spatially Varying Image Based Lighting by Light Probe Sequences, Capture, Processing and Rendering

    OpenAIRE

    Unger, Jonas; Gustavson, Stefan; Ynnerman, Anders

    2007-01-01

    We present a novel technique for capturing spatially or temporally resolved light probe sequences, and using them for image based lighting. For this purpose we have designed and built a real-time light probe, a catadioptric imaging system that can capture the full dynamic range of the lighting incident at each point in space at video frame rates, while being moved through a scene. The real-time light probe uses a digital imaging system which we have programmed to capture high quality, photome...

  10. Anticipatory Eye Movements While Watching Continuous Action Across Shots in Video Sequences: A Developmental Study.

    Science.gov (United States)

    Kirkorian, Heather L; Anderson, Daniel R

    2017-07-01

    Eye movements were recorded as 12-month-olds (n = 15), 4-year-olds (n = 17), and adults (n = 19) watched a 15-min video with sequences of shots conveying continuous motion. The central question was whether, and at what age, viewers anticipate the reappearance of objects following cuts to new shots. Adults were more likely than younger viewers to make anticipatory eye movements. Four-year-olds responded to transitions more slowly and tended to fixate the center of the screen. Infants' eye movement patterns reflected a tendency to react rather than anticipate. Findings are consistent with the hypothesis that adults integrate content across shots and understand how space is represented in edited video. Results are interpreted with respect to a developing understanding of film editing due to experience and cognitive maturation. © 2016 The Authors. Child Development © 2016 Society for Research in Child Development, Inc.

  11. Frequency Identification of Vibration Signals Using Video Camera Image Data

    Directory of Open Access Journals (Sweden)

    Chia-Hung Wu

    2012-10-01

    Full Text Available This study showed that an image data acquisition system connecting a high-speed camera or webcam to a notebook or personal computer (PC can precisely capture most dominant modes of vibration signal, but may involve the non-physical modes induced by the insufficient frame rates. Using a simple model, frequencies of these modes are properly predicted and excluded. Two experimental designs, which involve using an LED light source and a vibration exciter, are proposed to demonstrate the performance. First, the original gray-level resolution of a video camera from, for instance, 0 to 256 levels, was enhanced by summing gray-level data of all pixels in a small region around the point of interest. The image signal was further enhanced by attaching a white paper sheet marked with a black line on the surface of the vibration system in operation to increase the gray-level resolution. Experimental results showed that the Prosilica CV640C CMOS high-speed camera has the critical frequency of inducing the false mode at 60 Hz, whereas that of the webcam is 7.8 Hz. Several factors were proven to have the effect of partially suppressing the non-physical modes, but they cannot eliminate them completely. Two examples, the prominent vibration modes of which are less than the associated critical frequencies, are examined to demonstrate the performances of the proposed systems. In general, the experimental data show that the non-contact type image data acquisition systems are potential tools for collecting the low-frequency vibration signal of a system.

  12. Interpolation of missing data in image sequences.

    Science.gov (United States)

    Kokaram, A C; Morris, R D; Fitzgerald, W J; Rayner, P W

    1995-01-01

    This paper presents a number of model based interpolation schemes tailored to the problem of interpolating missing regions in image sequences. These missing regions may be of arbitrary size and of random, but known, location. This problem occurs regularly with archived film material. The film is abraded or obscured in patches, giving rise to bright and dark flashes, known as "dirt and sparkle" in the motion picture industry. Both 3-D autoregressive models and 3-D Markov random fields are considered in the formulation of the different reconstruction processes. The models act along motion directions estimated using a multiresolution block matching scheme. It is possible to address this sort of impulsive noise suppression problem with median filters, and comparisons with earlier work using multilevel median filters are performed. These comparisons demonstrate the higher reconstruction fidelity of the new interpolators.

  13. An infrared high rate video imager for various space applications

    Science.gov (United States)

    Svedhem, Hâkan; Koschny, Detlef

    2010-05-01

    Modern spacecraft with high data transmission capabilities have opened up the possibility to fly video rate imagers in space. Several fields concerned with observations of transient phenomena can benefit significantly from imaging at video frame rate. Some applications are observations and characterization of bolides/meteors, sprites, lightning, volcanic eruptions, and impacts on airless bodies. Applications can be found both on low and high Earth orbiting spacecraft as well as on planetary and lunar orbiters. The optimum wavelength range varies depending on the application but we will focus here on the near infrared, partly since it allows exploration of a new field and partly because it, in many cases, allows operation both during day and night. Such an instrument has to our knowledge never flown in space so far. The only sensors of a similar kind fly on US defense satellites for monitoring launches of ballistic missiles. The data from these sensors, however, is largely inaccessible to scientists. We have developed a bread-board version of such an instrument, the SPOSH-IR. The instrument is based on an earlier technology development - SPOSH - a Smart Panoramic Optical Sensor Head, for operation in the visible range, but with the sensor replace by a cooled IR detector and new optics. The instrument is using a Sofradir 320x256 pixel HgCdTe detector array with 30µm pixel size, mounted directly on top of a four stage thermoelectric Peltier cooler. The detector-cooler combination is integrated into an evacuated closed package with a glass window on its front side. The detector has a sensitive range between 0.8 and 2.5 µm. The optical part is a seven lens design with a focal length of 6 mm and a FOV 90deg by 72 deg optimized for use at SWIR. The detector operates at 200K while the optics operates at ambient temperature. The optics and electronics for the bread-board has been designed and built by Jena-Optronik, Jena, Germany. This talk will present the design and the

  14. The effects of frame-rate and image quality on perceived video quality in videoconferencing

    OpenAIRE

    Thakur, Aruna; Gao, Chaunsi; Larsson, Andreas; Parnes, Peter

    2001-01-01

    This report discusses the effect of frame-rate and image quality on the perceived video quality in a specific videoconferencing application (MarratechPro). Subjects with various videoconferencing experiences took part in four experiments wherein they gave their opinions on the quality of video upon the variations in frame-rate and image quality. The results of the experiments showed that the subjects preferred high frame rate over high image quality, under the condition of limited bandwidth. ...

  15. Quality Assessment of Adaptive Bitrate Videos using Image Metrics and Machine Learning

    DEFF Research Database (Denmark)

    Søgaard, Jacob; Forchhammer, Søren; Brunnström, Kjell

    2015-01-01

    Adaptive bitrate (ABR) streaming is widely used for distribution of videos over the internet. In this work, we investigate how well we can predict the quality of such videos using well-known image metrics, information about the bitrate levels, and a relatively simple machine learning method....... Quality assessment of ABR videos is a hard problem, but our initial results are promising. We obtain a Spearman rank order correlation of 0.88 using content-independent cross-validation....

  16. Traffic Video Image Segmentation Model Based on Bayesian and Spatio-Temporal Markov Random Field

    Science.gov (United States)

    Zhou, Jun; Bao, Xu; Li, Dawei; Yin, Yongwen

    2017-10-01

    Traffic video image is a kind of dynamic image and its background and foreground is changed at any time, which results in the occlusion. In this case, using the general method is more difficult to get accurate image segmentation. A segmentation algorithm based on Bayesian and Spatio-Temporal Markov Random Field is put forward, which respectively build the energy function model of observation field and label field to motion sequence image with Markov property, then according to Bayesian' rule, use the interaction of label field and observation field, that is the relationship of label field’s prior probability and observation field’s likelihood probability, get the maximum posterior probability of label field’s estimation parameter, use the ICM model to extract the motion object, consequently the process of segmentation is finished. Finally, the segmentation methods of ST - MRF and the Bayesian combined with ST - MRF were analyzed. Experimental results: the segmentation time in Bayesian combined with ST-MRF algorithm is shorter than in ST-MRF, and the computing workload is small, especially in the heavy traffic dynamic scenes the method also can achieve better segmentation effect.

  17. A multi-plane scout sequence using flash imaging.

    Science.gov (United States)

    Wright, S M; Wright, R M

    1988-01-01

    A new pulse sequence is presented for multi-plane imaging which simultaneously acquires images in the axial, coronal, and sagittal planes. Combined with FLASH imaging or other similar techniques, T1- and T2-weighted images in all three planes can be acquired in approximately 12 and 30 seconds, respectively. The sequence is easily implemented by modifying a multi-slice sequence to provide a rotation of gradient assignments between slice excitations. This sequence has been used extensively as a rapid "scout" scan. Several clinical examples are included.

  18. High-Performance Motion Estimation for Image Sensors with Video Compression

    OpenAIRE

    Weizhi Xu; Shouyi Yin; Leibo Liu; Zhiyong Liu; Shaojun Wei

    2015-01-01

    It is important to reduce the time cost of video compression for image sensors in video sensor network. Motion estimation (ME) is the most time-consuming part in video compression. Previous work on ME exploited intra-frame data reuse in a reference frame to improve the time efficiency but neglected inter-frame data reuse. We propose a novel inter-frame data reuse scheme which can exploit both intra-frame and inter-frame data reuse for ME in video compression (VC-ME). Pixels of reconstructed...

  19. What do we do with all this video? Better understanding public engagement for image and video annotation

    Science.gov (United States)

    Wiener, C.; Miller, A.; Zykov, V.

    2016-12-01

    Advanced robotic vehicles are increasingly being used by oceanographic research vessels to enable more efficient and widespread exploration of the ocean, particularly the deep ocean. With cutting-edge capabilities mounted onto robotic vehicles, data at high resolutions is being generated more than ever before, enabling enhanced data collection and the potential for broader participation. For example, high resolution camera technology not only improves visualization of the ocean environment, but also expands the capacity to engage participants remotely through increased use of telepresence and virtual reality techniques. Schmidt Ocean Institute is a private, non-profit operating foundation established to advance the understanding of the world's oceans through technological advancement, intelligent observation and analysis, and open sharing of information. Telepresence-enabled research is an important component of Schmidt Ocean Institute's science research cruises, which this presentation will highlight. Schmidt Ocean Institute is one of the only research programs that make their entire underwater vehicle dive series available online, creating a collection of video that enables anyone to follow deep sea research in real time. We encourage students, educators and the general public to take advantage of freely available dive videos. Additionally, other SOI-supported internet platforms, have engaged the public in image and video annotation activities. Examples of these new online platforms, which utilize citizen scientists to annotate scientific image and video data will be provided. This presentation will include an introduction to SOI-supported video and image tagging citizen science projects, real-time robot tracking, live ship-to-shore communications, and an array of outreach activities that enable scientists to interact with the public and explore the ocean in fascinating detail.

  20. Multimodal Translation System Using Texture-Mapped Lip-Sync Images for Video Mail and Automatic Dubbing Applications

    Directory of Open Access Journals (Sweden)

    Nakamura Satoshi

    2004-01-01

    Full Text Available We introduce a multimodal English-to-Japanese and Japanese-to-English translation system that also translates the speaker's speech motion by synchronizing it to the translated speech. This system also introduces both a face synthesis technique that can generate any viseme lip shape and a face tracking technique that can estimate the original position and rotation of a speaker's face in an image sequence. To retain the speaker's facial expression, we substitute only the speech organ's image with the synthesized one, which is made by a 3D wire-frame model that is adaptable to any speaker. Our approach provides translated image synthesis with an extremely small database. The tracking motion of the face from a video image is performed by template matching. In this system, the translation and rotation of the face are detected by using a 3D personal face model whose texture is captured from a video frame. We also propose a method to customize the personal face model by using our GUI tool. By combining these techniques and the translated voice synthesis technique, an automatic multimodal translation can be achieved that is suitable for video mail or automatic dubbing systems into other languages.

  1. Automatic real-time tracking of fetal mouth in fetoscopic video sequence for supporting fetal surgeries

    Science.gov (United States)

    Xu, Rong; Xie, Tianliang; Ohya, Jun; Zhang, Bo; Sato, Yoshinobu; Fujie, Masakatsu G.

    2013-03-01

    Recently, a minimally invasive surgery (MIS) called fetoscopic tracheal occlusion (FETO) was developed to treat severe congenital diaphragmatic hernia (CDH) via fetoscopy, by which a detachable balloon is placed into the fetal trachea for preventing pulmonary hypoplasia through increasing the pressure of the chest cavity. This surgery is so dangerous that a supporting system for navigating surgeries is deemed necessary. In this paper, to guide a surgical tool to be inserted into the fetal trachea, an automatic approach is proposed to detect and track the fetal face and mouth via fetoscopic video sequencing. More specifically, the AdaBoost algorithm is utilized as a classifier to detect the fetal face based on Haarlike features, which calculate the difference between the sums of the pixel intensities in each adjacent region at a specific location in a detection window. Then, the CamShift algorithm based on an iterative search in a color histogram is applied to track the fetal face, and the fetal mouth is fitted by an ellipse detected via an improved iterative randomized Hough transform approach. The experimental results demonstrate that the proposed automatic approach can accurately detect and track the fetal face and mouth in real-time in a fetoscopic video sequence, as well as provide an effective and timely feedback to the robot control system of the surgical tool for FETO surgeries.

  2. 17 CFR 232.304 - Graphic, image, audio and video material.

    Science.gov (United States)

    2010-04-01

    ... delivered to investors and others is deemed part of the electronic filing and subject to the civil liability..., image, audio or video material, they are not subject to the civil liability and anti-fraud provisions of...

  3. Do Stereotypic Images in Video Games Affect Attitudes and Behavior? Adolescents' Perspectives.

    Science.gov (United States)

    Henning, Alexandra; Brenick, Alaina; Killen, Melanie; O'Connor, Alexander; Collins, Michael J

    This study examined adolescents' attitudes about video games along with their self-reported play frequency. Ninth and eleventh grade students (N = 361), approximately evenly divided by grade and gender, were surveyed about whether video games have stereotypic images, involve harmful consequences or affect one's attitudes, whether game playing should be regulated by parents or the government, and whether game playing is a personal choice. Adolescents who played video games frequently showed decreased concern about the effects that games with negatively stereotyped images may have on the players' attitudes compared to adolescents who played games infrequently or not at all. With age, adolescents were more likely to view images as negative, but were also less likely to recognize stereotypic images of females as harmful and more likely to judge video-game playing as a personal choice. The paper discusses other findings in relation to research on adolescents' social cognitive judgments.

  4. Do Stereotypic Images in Video Games Affect Attitudes and Behavior? Adolescents’ Perspectives

    Science.gov (United States)

    Henning, Alexandra; Brenick, Alaina; Killen, Melanie; O’Connor, Alexander; Collins, Michael J.

    2015-01-01

    This study examined adolescents’ attitudes about video games along with their self-reported play frequency. Ninth and eleventh grade students (N = 361), approximately evenly divided by grade and gender, were surveyed about whether video games have stereotypic images, involve harmful consequences or affect one’s attitudes, whether game playing should be regulated by parents or the government, and whether game playing is a personal choice. Adolescents who played video games frequently showed decreased concern about the effects that games with negatively stereotyped images may have on the players’ attitudes compared to adolescents who played games infrequently or not at all. With age, adolescents were more likely to view images as negative, but were also less likely to recognize stereotypic images of females as harmful and more likely to judge video-game playing as a personal choice. The paper discusses other findings in relation to research on adolescents’ social cognitive judgments. PMID:25729336

  5. Fast Orientation of Video Images of Buildings Acquired from a UAV without Stabilization

    National Research Council Canada - National Science Library

    Kedzierski, Michal; Delis, Paulina

    2016-01-01

    The aim of this research was to assess the possibility of conducting an absolute orientation procedure for video imagery, in which the external orientation for the first image was typical for aerial...

  6. Video Object Tracking in Neural Axons with Fluorescence Microscopy Images

    Directory of Open Access Journals (Sweden)

    Liang Yuan

    2014-01-01

    tracking. In this paper, we describe two automated tracking methods for analyzing neurofilament movement based on two different techniques: constrained particle filtering and tracking-by-detection. First, we introduce the constrained particle filtering approach. In this approach, the orientation and position of a particle are constrained by the axon’s shape such that fewer particles are necessary for tracking neurofilament movement than object tracking techniques based on generic particle filtering. Secondly, a tracking-by-detection approach to neurofilament tracking is presented. For this approach, the axon is decomposed into blocks, and the blocks encompassing the moving neurofilaments are detected by graph labeling using Markov random field. Finally, we compare two tracking methods by performing tracking experiments on real time-lapse image sequences of neurofilament movement, and the experimental results show that both methods demonstrate good performance in comparison with the existing approaches, and the tracking accuracy of the tracing-by-detection approach is slightly better between the two.

  7. Research and implementation of video image acquisition and processing based on Java and JMF

    Science.gov (United States)

    Qin, Jinlei; Li, Zheng; Niu, Yuguang

    2012-01-01

    The article put forward a method which had been used for video image acquisition and processing, and a system based on Java media framework (JMF) had been implemented by it. The method could be achieved not only by B/S mode but also by C/S mode taking advantage of the predominance of the Java language. Some key issues such as locating video data source, playing video, video image acquisition and processing and so on had been expatiated in detail. The operation results of the system show that this method is fully compatible with common video capture device. At the same time the system possesses many excellences as lower cost, more powerful, easier to develop and cross-platform etc. Finally the application prospect of the method which is based on java and JMF is pointed out.

  8. Moving object detection in top-view aerial videos improved by image stacking

    Science.gov (United States)

    Teutsch, Michael; Krüger, Wolfgang; Beyerer, Jürgen

    2017-08-01

    Image stacking is a well-known method that is used to improve the quality of images in video data. A set of consecutive images is aligned by applying image registration and warping. In the resulting image stack, each pixel has redundant information about its intensity value. This redundant information can be used to suppress image noise, resharpen blurry images, or even enhance the spatial image resolution as done in super-resolution. Small moving objects in the videos usually get blurred or distorted by image stacking and thus need to be handled explicitly. We use image stacking in an innovative way: image registration is applied to small moving objects only, and image warping blurs the stationary background that surrounds the moving objects. Our video data are coming from a small fixed-wing unmanned aerial vehicle (UAV) that acquires top-view gray-value images of urban scenes. Moving objects are mainly cars but also other vehicles such as motorcycles. The resulting images, after applying our proposed image stacking approach, are used to improve baseline algorithms for vehicle detection and segmentation. We improve precision and recall by up to 0.011, which corresponds to a reduction of the number of false positive and false negative detections by more than 3 per second. Furthermore, we show how our proposed image stacking approach can be implemented efficiently.

  9. An Experimental Video Disc for Map and Image Display,

    Science.gov (United States)

    1984-01-01

    a member of the American Y Codes Society of Photogrammetry . D va±1 apnd/or ABSTRACT A cooperative effort between four government recently resulted in...video tapes# to movie film, to transparencies, to paper photographic prints, to paper maps, charts, and documents. Bach of these media has its own space...perspective terrain views, engineering "* drawihgs, harbor charts, ground photographs, slides, movies , video tapes# documents, and organizaticnal logos

  10. No Reference Prediction of Quality Metrics for H.264 Compressed Infrared Image Sequences for UAV Applications

    DEFF Research Database (Denmark)

    Hossain, Kabir; Mantel, Claire; Forchhammer, Søren

    2018-01-01

    The framework for this research work is the acquisition of Infrared (IR) images from Unmanned Aerial Vehicles (UAV). In this paper we consider the No-Reference (NR) prediction of Full Reference Quality Metrics for Infrared (IR) video sequences which are compressed and thus distorted by an H.264...... and temporal perceptual information. Those features are then mapped, using a machine learning (ML) algorithm, the Support Vector Regression (SVR), to the quality scores of Full Reference (FR) quality metrics. The novelty of this work is to design a NR framework for the prediction of quality metrics by applying...... with the true FR quality metrics scores of four images metrics: PSNR, NQM, SSIM and UQI and one video metric: VQM. Results show that our technique achieves a fairly reasonable performance. The improved performance obtained in SROCC and LCC is up to 0.99 and the RMSE is reduced to as little as 0.01 between...

  11. Video-rate computational super-resolution and integral imaging at longwave-infrared wavelengths

    OpenAIRE

    Preciado, Miguel A.; Carles, Guillem; Harvey, Andrew R.

    2017-01-01

    We report the first computational super-resolved, multi-camera integral imaging at long-wave infrared (LWIR) wavelengths. A synchronized array of FLIR Lepton cameras was assembled, and computational super-resolution and integral-imaging reconstruction employed to generate video with light-field imaging capabilities, such as 3D imaging and recognition of partially obscured objects, while also providing a four-fold increase in effective pixel count. This approach to high-resolution imaging enab...

  12. Uncompressed video image transmission of laparoscopic or endoscopic surgery for telemedicine.

    Science.gov (United States)

    Huang, Ke-Jian; Qiu, Zheng-Jun; Fu, Chun-Yu; Shimizu, Shuji; Okamura, Koji

    2008-06-01

    Traditional narrowband telemedicine cannot provide quality dynamic images. We conducted videoconferences of laparoscopic and endoscopic operations via an uncompressed video transmission technique. A superfast broadband Internet link was set up between Shanghai in the People's Republic of China and Fukuoka in Japan. Uncompressed dynamic video images of laparoscopic and endoscopic operations were transmitted by a digital video transfer system (DVTS). Seven teleconferences were conducted between June 2005 and June 2007. Of the 7 teleconferences, 5 were live surgical demonstrations and 3 were recorded video teleconsultations. Smoothness of the motion picture, sharpness of images, and clarity of sound were benefited by this form of telemedicine based upon DVTS. Telemedicine based upon DVTS is a superior choice for laparoscopic and endoscopic skill training across the borders.

  13. Measuring Sandy Bottom Dynamics by Exploiting Depth from Stereo Video Sequences

    DEFF Research Database (Denmark)

    Musumeci, Rosaria E.; Farinella, Giovanni M.; Foti, Enrico

    2013-01-01

    In this paper an imaging system for measuring sandy bottom dynamics is proposed. The system exploits stereo sequences and projected laser beams to build the 3D shape of the sandy bottom during time. The reconstruction is used by experts of the field to perform accurate measurements and analysis...

  14. Hardware architectures for real time processing of High Definition video sequences

    OpenAIRE

    Genovese, Mariangela

    2014-01-01

    Actually, application fields, such as medicine, space exploration, surveillance, authentication, HDTV, and automated industry inspection, require capturing, storing and processing continuous streams of video data. Consequently, different process techniques (video enhancement, segmentation, object detection, or video compression, as examples) are involved in these applications. Such techniques often require a significant number of operations depending on the algorithm complexity and the video ...

  15. Study of recognizing multiple persons' complicated hand gestures from the video sequence acquired by a moving camera

    Science.gov (United States)

    Dan, Luo; Ohya, Jun

    2010-02-01

    Recognizing hand gestures from the video sequence acquired by a dynamic camera could be a useful interface between humans and mobile robots. We develop a state based approach to extract and recognize hand gestures from moving camera images. We improved Human-Following Local Coordinate (HFLC) System, a very simple and stable method for extracting hand motion trajectories, which is obtained from the located human face, body part and hand blob changing factor. Condensation algorithm and PCA-based algorithm was performed to recognize extracted hand trajectories. In last research, this Condensation Algorithm based method only applied for one person's hand gestures. In this paper, we propose a principal component analysis (PCA) based approach to improve the recognition accuracy. For further improvement, temporal changes in the observed hand area changing factor are utilized as new image features to be stored in the database after being analyzed by PCA. Every hand gesture trajectory in the database is classified into either one hand gesture categories, two hand gesture categories, or temporal changes in hand blob changes. We demonstrate the effectiveness of the proposed method by conducting experiments on 45 kinds of sign language based Japanese and American Sign Language gestures obtained from 5 people. Our experimental recognition results show better performance is obtained by PCA based approach than the Condensation algorithm based method.

  16. Based on photogrammetry methodological sequence image 3D movement comparisons

    Science.gov (United States)

    Zhang, Chunsen; He, Shaojun

    2005-10-01

    The sequence image 3D movement analysis is method that estimates 3D movement parameter from 2D image sequence or 3D "image" (object side) sequence. In theory, monocular and binocular sequence image all can fulfill the three dimensions movement analyses, but there are distinctions in the complexity of computing and accuracy of computing result. In order to compare the accuracy of estimates 3D movement parameter from 2D image sequence or 3D "image" sequence, the article uses ideas of "relative orientation" and "space similitude transform" in photogrammetry for reference, presents an approach that connects the image data with real three dimensions space by making use of the result of calibration and other additional conditions to unify the computing result of monocular and binocular sequence image to object side coordinate system which origin point is one fixed point in object side, this make it possible to compare their results. The experiment results of real data, which use the method, are given.

  17. From computer images to video presentation: Enhancing technology transfer

    Science.gov (United States)

    Beam, Sherilee F.

    1994-01-01

    With NASA placing increased emphasis on transferring technology to outside industry, NASA researchers need to evaluate many aspects of their efforts in this regard. Often it may seem like too much self-promotion to many researchers. However, industry's use of video presentations in sales, advertising, public relations and training should be considered. Today, the most typical presentation at NASA is through the use of vu-graphs (overhead transparencies) which can be effective for text or static presentations. For full blown color and sound presentations, however, the best method is videotape. In fact, it is frequently more convenient due to its portability and the availability of viewing equipment. This talk describes techniques for creating a video presentation through the use of a combined researcher and video professional team.

  18. Robust real-time segmentation of images and videos using a smooth-spline snake-based algorithm.

    Science.gov (United States)

    Precioso, Frederic; Barlaud, Michel; Blu, Thierry; Unser, Michael

    2005-07-01

    This paper deals with fast image and video segmentation using active contours. Region-based active contours using level sets are powerful techniques for video segmentation, but they suffer from large computational cost. A parametric active contour method based on B-Spline interpolation has been proposed in to highly reduce the computational cost, but this method is sensitive to noise. Here, we choose to relax the rigid interpolation constraint in order to robustify our method in the presence of noise: by using smoothing splines, we trade a tunable amount of interpolation error for a smoother spline curve. We show by experiments on natural sequences that this new flexibility yields segmentation results of higher quality at no additional computational cost. Hence, real-time processing for moving objects segmentation is preserved.

  19. Predicting human activities in sequences of actions in RGB-D videos

    Science.gov (United States)

    Jardim, David; Nunes, Luís.; Dias, Miguel

    2017-03-01

    In our daily activities we perform prediction or anticipation when interacting with other humans or with objects. Prediction of human activity made by computers has several potential applications: surveillance systems, human computer interfaces, sports video analysis, human-robot-collaboration, games and health-care. We propose a system capable of recognizing and predicting human actions using supervised classifiers trained with automatically labeled data evaluated in our human activity RGB-D dataset (recorded with a Kinect sensor) and using only the position of the main skeleton joints to extract features. Using conditional random fields (CRFs) to model the sequential nature of actions in a sequence has been used before, but where other approaches try to predict an outcome or anticipate ahead in time (seconds), we try to predict what will be the next action of a subject. Our results show an activity prediction accuracy of 89.9% using an automatically labeled dataset.

  20. [A new laser scan system for video ophthalmoscopy. Initial clinical experiences also in relation to digital image processing].

    Science.gov (United States)

    Fabian, E; Mertz, M; Hofmann, H; Wertheimer, R; Foos, C

    1990-06-01

    The clinical advantages of a scanning laser ophthalmoscope (SLO) and video imaging of fundus pictures are described. Image quality (contrast, depth of field) and imaging possibilities (confocal stop) are assessed. Imaging with different lasers (argon, He-Ne) and changes in imaging rendered possible by confocal alignment of the imaging optics are discussed. Hard copies from video images are still of inferior quality compared to fundus photographs. Methods of direct processing and retrieval of digitally stored SLO video fundus images are illustrated by examples. Modifications for a definitive laser scanning system - in regard to the field of view and the quality of hard copies - are proposed.

  1. Exemplar-Based Image and Video Stylization Using Fully Convolutional Semantic Features.

    Science.gov (United States)

    Zhu, Feida; Yan, Zhicheng; Bu, Jiajun; Yu, Yizhou

    2017-05-10

    Color and tone stylization in images and videos strives to enhance unique themes with artistic color and tone adjustments. It has a broad range of applications from professional image postprocessing to photo sharing over social networks. Mainstream photo enhancement softwares, such as Adobe Lightroom and Instagram, provide users with predefined styles, which are often hand-crafted through a trial-and-error process. Such photo adjustment tools lack a semantic understanding of image contents and the resulting global color transform limits the range of artistic styles it can represent. On the other hand, stylistic enhancement needs to apply distinct adjustments to various semantic regions. Such an ability enables a broader range of visual styles. In this paper, we first propose a novel deep learning architecture for exemplar-based image stylization, which learns local enhancement styles from image pairs. Our deep learning architecture consists of fully convolutional networks (FCNs) for automatic semantics-aware feature extraction and fully connected neural layers for adjustment prediction. Image stylization can be efficiently accomplished with a single forward pass through our deep network. To extend our deep network from image stylization to video stylization, we exploit temporal superpixels (TSPs) to facilitate the transfer of artistic styles from image exemplars to videos. Experiments on a number of datasets for image stylization as well as a diverse set of video clips demonstrate the effectiveness of our deep learning architecture.

  2. Facial attractiveness ratings from video-clips and static images tell the same story.

    Science.gov (United States)

    Rhodes, Gillian; Lie, Hanne C; Thevaraja, Nishta; Taylor, Libby; Iredell, Natasha; Curran, Christine; Tan, Shi Qin Claire; Carnemolla, Pia; Simmons, Leigh W

    2011-01-01

    Most of what we know about what makes a face attractive and why we have the preferences we do is based on attractiveness ratings of static images of faces, usually photographs. However, several reports that such ratings fail to correlate significantly with ratings made to dynamic video clips, which provide richer samples of appearance, challenge the validity of this literature. Here, we tested the validity of attractiveness ratings made to static images, using a substantial sample of male faces. We found that these ratings agreed very strongly with ratings made to videos of these men, despite the presence of much more information in the videos (multiple views, neutral and smiling expressions and speech-related movements). Not surprisingly, given this high agreement, the components of video-attractiveness were also very similar to those reported previously for static-attractiveness. Specifically, averageness, symmetry and masculinity were all significant components of attractiveness rated from videos. Finally, regression analyses yielded very similar effects of attractiveness on success in obtaining sexual partners, whether attractiveness was rated from videos or static images. These results validate the widespread use of attractiveness ratings made to static images in evolutionary and social psychological research. We speculate that this validity may stem from our tendency to make rapid and robust judgements of attractiveness.

  3. Thinking Images: Doing Philosophy in Film and Video

    Science.gov (United States)

    Parkes, Graham

    2009-01-01

    Over the past several decades film and video have been steadily infiltrating the philosophy curriculum at colleges and universities. Traditionally, teachers of philosophy have not made much use of "audiovisual aids" in the classroom beyond the chalk board or overhead projector, with only the more adventurous playing audiotapes, for example, or…

  4. Video surveillance of epilepsy patients using color image processing

    DEFF Research Database (Denmark)

    Bager, Gitte; Vilic, Kenan; Vilic, Adnan

    2014-01-01

    This paper introduces a method for tracking patients under video surveillance based on a color marker system. The patients are not restricted in their movements, which requires a tracking system that can overcome non-ideal scenes e.g. occlusions, very fast movements, lighting issues and other mov...

  5. Nearshore subtidal bathymetry from time-exposure video images

    NARCIS (Netherlands)

    Aarninkhof, S.G.J.; Ruessink, B.G.; Roelvink, J.A.

    2005-01-01

    Time-averaged (over many wave periods) nearshore video observations show the process of wave breaking as one or more white alongshore bands of high intensity. Across a known depth profile, similar bands of dissipation can be predicted with a model describing the time-averaged cross-shore evolution

  6. Video Surveillance of Epilepsy Patients using Color Image Processing

    DEFF Research Database (Denmark)

    Bager, Gitte; Vilic, Kenan; Alving, Jørgen

    2007-01-01

    This report introduces a method for tracking of patients under video surveillance based on a marker system. The patients are not restricted in their movements, which requires a tracking system that can overcome non-ideal scenes e.g. occlusions, very fast movements, lightning issues and other moving...

  7. Quality Assessment of Mapping Building Textures from Infrared Image Sequences

    Science.gov (United States)

    Hoegner, L.; Iwaszczuk, D.; Stilla, U.

    2012-07-01

    Generation and texturing of building models is a fast developing field of research. Several techniques have been developed to extract building geometry and textures from multiple images and image sequences. In this paper, these techniques are discussed and extended to automatically add new textures from infrared (IR) image sequences to existing building models. In contrast to existing work, geometry and textures are not generated together from the same dataset but the textures are extracted from the image sequence and matched to an existing geo-referenced 3D building model. The texture generation is divided in two main parts. The first part deals with the estimation and refinement of the exterior camera orientation. Feature points are extracted in the images and used as tie points in the sequence. A recorded exterior orientation of the camera s added to these homologous points and a bundle adjustment is performed starting on image pairs and combining the hole sequence. A given 3d model of the observed building is additionally added to introduce further constraint as ground control points in the bundle adjustment. The second part includes the extraction of textures from the images and the combination of textures from different images of the sequence. Using the reconstructed exterior camera orientation for every image of the sequence, the visible facades are projected into the image and texture is extracted. These textures normally contain only parts of the facade. The partial textures extracted from all images are combined to one facade texture. This texture is stored with a 3D reference to the corresponding facade. This allows searching for features in textures and localising those features in 3D space. It will be shown, that the proposed strategy allows texture extraction and mapping even for big building complexes with restricted viewing possibilities and for images with low optical resolution.

  8. Measuring coupled oscillations using an automated video analysis technique based on image recognition

    Energy Technology Data Exchange (ETDEWEB)

    Monsoriu, Juan A; Gimenez, Marcos H; Riera, Jaime; Vidaurre, Ana [Departamento de Fisica Aplicada, Universidad Politecnica de Valencia, E-46022 Valencia (Spain)

    2005-11-01

    The applications of the digital video image to the investigation of physical phenomena have increased enormously in recent years. The advances in computer technology and image recognition techniques allow the analysis of more complex problems. In this work, we study the movement of a damped coupled oscillation system. The motion is considered as a linear combination of two normal modes, i.e. the symmetric and antisymmetric modes. The image of the experiment is recorded with a video camera and analysed by means of software developed in our laboratory. The results show a very good agreement with the theory.

  9. VIPER: a general-purpose digital image-processing system applied to video microscopy.

    Science.gov (United States)

    Brunner, M; Ittner, W

    1988-01-01

    This paper describes VIPER, the video image-processing system Erlangen. It consists of a general purpose microcomputer, commercially available image-processing hardware modules connected directly to the computer, video input/output-modules such as a TV camera, video recorders and monitors, and a software package. The modular structure and the capabilities of this system are explained. The software is user-friendly, menu-driven and performs image acquisition, transfers, greyscale processing, arithmetics, logical operations, filtering display, colour assignment, graphics, and a couple of management functions. More than 100 image-processing functions are implemented. They are available either by typing a key or by a simple call to the function-subroutine library in application programs. Examples are supplied in the area of biomedical research, e.g. in in-vivo microscopy.

  10. Spectral optical coherence tomography in video-rate and 3D imaging of contact lens wear.

    Science.gov (United States)

    Kaluzny, Bartlomiej J; Fojt, Wojciech; Szkulmowska, Anna; Bajraszewski, Tomasz; Wojtkowski, Maciej; Kowalczyk, Andrzej

    2007-12-01

    To present the applicability of spectral optical coherence tomography (SOCT) for video-rate and three-dimensional imaging of a contact lens on the eye surface. The SOCT prototype instrument constructed at Nicolaus Copernicus University (Torun, Poland) is based on Fourier domain detection, which enables high sensitivity (96 dB) and increases the speed of imaging 60 times compared with conventional optical coherence tomography techniques. Consequently, video-rate imaging and three-dimensional reconstructions can be achieved, preserving the high quality of the image. The instrument operates under clinical conditions in the Ophthalmology Department (Collegium Medicum Nicolaus Copernicus University, Bydgoszcz, Poland). A total of three eyes fitted with different contact lenses were examined with the aid of the instrument. Before SOCT measurements, slit lamp examinations were performed. Data, which are representative for each imaging mode, are presented. The instrument provided high-resolution (4 microm axial x 10 microm transverse) tomograms with an acquisition time of 40 micros per A-scan. Video-rate imaging allowed the simultaneous quantitative evaluation of the movement of the contact lens and assessment of the fitting relationship between the lens and the ocular surface. Three-dimensional scanning protocols further improved lens visualization and fit evaluation. SOCT allows video-rate and three-dimensional cross-sectional imaging of the eye fitted with a contact lens. The analysis of both imaging modes suggests the future applicability of this technology to the contact lens field.

  11. Achieving real-time capsule endoscopy (CE) video visualization through panoramic imaging

    Science.gov (United States)

    Yi, Steven; Xie, Jean; Mui, Peter; Leighton, Jonathan A.

    2013-02-01

    In this paper, we mainly present a novel and real-time capsule endoscopy (CE) video visualization concept based on panoramic imaging. Typical CE videos run about 8 hours and are manually reviewed by physicians to locate diseases such as bleedings and polyps. To date, there is no commercially available tool capable of providing stabilized and processed CE video that is easy to analyze in real time. The burden on physicians' disease finding efforts is thus big. In fact, since the CE camera sensor has a limited forward looking view and low image frame rate (typical 2 frames per second), and captures very close range imaging on the GI tract surface, it is no surprise that traditional visualization method based on tracking and registration often fails to work. This paper presents a novel concept for real-time CE video stabilization and display. Instead of directly working on traditional forward looking FOV (field of view) images, we work on panoramic images to bypass many problems facing traditional imaging modalities. Methods on panoramic image generation based on optical lens principle leading to real-time data visualization will be presented. In addition, non-rigid panoramic image registration methods will be discussed.

  12. Cross-utilizing hyperchaotic and DNA sequences for image encryption

    Science.gov (United States)

    Zhan, Kun; Wei, Dong; Shi, Jinhui; Yu, Jun

    2017-01-01

    The hyperchaotic sequence and the DNA sequence are utilized jointly for image encryption. A four-dimensional hyperchaotic system is used to generate a pseudorandom sequence. The main idea is to apply the hyperchaotic sequence to almost all steps of the encryption. All intensity values of an input image are converted to a serial binary digit stream, and the bitstream is scrambled globally by the hyperchaotic sequence. DNA algebraic operation and complementation are performed between the hyperchaotic sequence and the DNA sequence to obtain a robust encryption performance. The experiment results demonstrate that the encryption algorithm achieves the performance of the state-of-the-art methods in term of quality, security, and robustness against noise and cropping attack.

  13. Music video shot segmentation using independent component analysis and keyframe extraction based on image complexity

    Science.gov (United States)

    Li, Wei; Chen, Ting; Zhang, Wenjun; Shi, Yunyu; Li, Jun

    2012-04-01

    In recent years, Music video data is increasing at an astonishing speed. Shot segmentation and keyframe extraction constitute a fundamental unit in organizing, indexing, retrieving video content. In this paper a unified framework is proposed to detect the shot boundaries and extract the keyframe of a shot. Music video is first segmented to shots by illumination-invariant chromaticity histogram in independent component (IC) analysis feature space .Then we presents a new metric, image complexity, to extract keyframe in a shot which is computed by ICs. Experimental results show the framework is effective and has a good performance.

  14. Image denoising method based on FPGA in digital video transmission

    Science.gov (United States)

    Xiahou, Yaotao; Wang, Wanping; Huang, Tao

    2017-11-01

    In the image acquisition and transmission link, due to the acquisition of equipment and methods, the image would suffer some different degree of interference ,and the interference will reduce the quality of image which would influence the subsequent processing. Therefore, the image filtering and image enhancement are particularly important.The traditional image denoising algorithm smoothes the image while removing the noise, so that the details of the image are lost. In order to improve image quality and save image detail, this paper proposes an improved filtering algorithm based on edge detection, Gaussian filter and median filter. This method can not only reduce the noise effectively, but also the image details are saved relatively well, and the FPGA implementation scheme of this filter algorithm is also given in this paper.

  15. The Impact of Video Compression on Remote Cardiac Pulse Measurement Using Imaging Photoplethysmography

    Science.gov (United States)

    2017-05-30

    quality is human subjective perception assessed by a Mean Opinion Score (MOS). Alternatively, video quality may be assessed using one of numerous...cameras. Synchronization of the image capture from the array was achieved using a PCIe-6323 data acquisition card (National Instruments, Austin...large reductions of either video resolution or frame rate did not strongly impact iPPG pulse rate measurements [9]. A balanced approach may yield

  16. Learning with Technology: Video Modeling with Concrete-Representational-Abstract Sequencing for Students with Autism Spectrum Disorder

    Science.gov (United States)

    Yakubova, Gulnoza; Hughes, Elizabeth M.; Shinaberry, Megan

    2016-01-01

    The purpose of this study was to determine the effectiveness of a video modeling intervention with concrete-representational-abstract instructional sequence in teaching mathematics concepts to students with autism spectrum disorder (ASD). A multiple baseline across skills design of single-case experimental methodology was used to determine the…

  17. Enrichment of words by visual images: books, slides, and videos.

    Science.gov (United States)

    Brozek, J M

    1999-08-01

    This article reviews additions to 3 ways of visually enriching verbal accounts of the history of psychology: illustrated books, slides, and videos. Although each approach has its limitations and its merits, taken together they constitute a significant addition to the printed word. As such, they broaden the toolkits of both the learners and the teachers of the history of psychology. Reference is also made to 3 earlier publications.

  18. Assessing the Content of YouTube Videos in Educating Patients Regarding Common Imaging Examinations.

    Science.gov (United States)

    Rosenkrantz, Andrew B; Won, Eugene; Doshi, Ankur M

    2016-12-01

    To assess the content of currently available YouTube videos seeking to educate patients regarding commonly performed imaging examinations. After initial testing of possible search terms, the first two pages of YouTube search results for "CT scan," "MRI," "ultrasound patient," "PET scan," and "mammogram" were reviewed to identify educational patient videos created by health organizations. Sixty-three included videos were viewed and assessed for a range of features. Average views per video were highest for MRI (293,362) and mammography (151,664). Twenty-seven percent of videos used a nontraditional format (eg, animation, song, humor). All videos (100.0%) depicted a patient undergoing the examination, 84.1% a technologist, and 20.6% a radiologist; 69.8% mentioned examination lengths, 65.1% potential pain/discomfort, 41.3% potential radiation, 36.5% a radiology report/results, 27.0% the radiologist's role in interpretation, and 13.3% laboratory work. For CT, 68.8% mentioned intravenous contrast and 37.5% mentioned contrast safety. For MRI, 93.8% mentioned claustrophobia, 87.5% noise, 75.0% need to sit still, 68.8% metal safety, 50.0% intravenous contrast, and 0.0% contrast safety. For ultrasound, 85.7% mentioned use of gel. For PET, 92.3% mentioned radiotracer injection, 61.5% fasting, and 46.2% diabetic precautions. For mammography, unrobing, avoiding deodorant, and possible additional images were all mentioned by 63.6%; dense breasts were mentioned by 0.0%. Educational patient videos on YouTube regarding common imaging examinations received high public interest and may provide a valuable patient resource. Videos most consistently provided information detailing the examination experience and less consistently provided safety information or described the presence and role of the radiologist. Copyright © 2016 American College of Radiology. Published by Elsevier Inc. All rights reserved.

  19. VQone MATLAB toolbox: A graphical experiment builder for image and video quality evaluations: VQone MATLAB toolbox.

    Science.gov (United States)

    Nuutinen, Mikko; Virtanen, Toni; Rummukainen, Olli; Häkkinen, Jukka

    2016-03-01

    This article presents VQone, a graphical experiment builder, written as a MATLAB toolbox, developed for image and video quality ratings. VQone contains the main elements needed for the subjective image and video quality rating process. This includes building and conducting experiments and data analysis. All functions can be controlled through graphical user interfaces. The experiment builder includes many standardized image and video quality rating methods. Moreover, it enables the creation of new methods or modified versions from standard methods. VQone is distributed free of charge under the terms of the GNU general public license and allows code modifications to be made so that the program's functions can be adjusted according to a user's requirements. VQone is available for download from the project page (http://www.helsinki.fi/psychology/groups/visualcognition/).

  20. Safety Assessment of Advanced Imaging Sequences I: Measurements

    DEFF Research Database (Denmark)

    Jensen, Jørgen Arendt; Rasmussen, Morten Fischer; Pihl, Michael Johannes

    2016-01-01

    A method for rapid measurement of intensities (Ispta), mechanical index (MI), and probe surface temperature for any ultrasound scanning sequence is presented. It uses the scanner’s sampling capability to give an accurate measurement of the whole imaging sequence for all emissions to yield the tru...

  1. PIZZARO: Forensic analysis and restoration of image and video data

    Czech Academy of Sciences Publication Activity Database

    Kamenický, Jan; Bartoš, Michal; Flusser, Jan; Mahdian, Babak; Kotera, Jan; Novozámský, Adam; Saic, Stanislav; Šroubek, Filip; Šorel, Michal; Zita, Aleš; Zitová, Barbara; Šíma, Z.; Švarc, P.; Hořínek, J.

    2016-01-01

    Roč. 264, č. 1 (2016), s. 153-166 ISSN 0379-0738 R&D Projects: GA MV VG20102013064; GA ČR GA13-29225S Institutional support: RVO:67985556 Keywords : Image forensic analysis * Image restoration * Image tampering detection * Image source identification Subject RIV: JD - Computer Applications, Robotics Impact factor: 1.989, year: 2016 http://library.utia.cas.cz/separaty/2016/ZOI/kamenicky-0459504.pdf

  2. Fast Registration of Terrestrial LIDAR Point Cloud and Sequence Images

    Science.gov (United States)

    Shao, J.; Zhang, W.; Zhu, Y.; Shen, A.

    2017-09-01

    Image has rich color information, and it can help to promote recognition and classification of point cloud. The registration is an important step in the application of image and point cloud. In order to give the rich texture and color information for LiDAR point cloud, the paper researched a fast registration method of point cloud and sequence images based on the ground-based LiDAR system. First, calculating transformation matrix of one of sequence images based on 2D image and LiDAR point cloud; second, using the relationships of position and attitude information among multi-angle sequence images to calculate all transformation matrixes in the horizontal direction; last, completing the registration of point cloud and sequence images based on the collinear condition of image point, projective center and LiDAR point. The experimental results show that the method is simple and fast, and the stitching error between adjacent images is litter; meanwhile, the overall registration accuracy is high, and the method can be used in engineering application.

  3. Infrared thermal facial image sequence registration analysis and verification

    Science.gov (United States)

    Chen, Chieh-Li; Jian, Bo-Lin

    2015-03-01

    To study the emotional responses of subjects to the International Affective Picture System (IAPS), infrared thermal facial image sequence is preprocessed for registration before further analysis such that the variance caused by minor and irregular subject movements is reduced. Without affecting the comfort level and inducing minimal harm, this study proposes an infrared thermal facial image sequence registration process that will reduce the deviations caused by the unconscious head shaking of the subjects. A fixed image for registration is produced through the localization of the centroid of the eye region as well as image translation and rotation processes. Thermal image sequencing will then be automatically registered using the two-stage genetic algorithm proposed. The deviation before and after image registration will be demonstrated by image quality indices. The results show that the infrared thermal image sequence registration process proposed in this study is effective in localizing facial images accurately, which will be beneficial to the correlation analysis of psychological information related to the facial area.

  4. Learning Computational Models of Video Memorability from fMRI Brain Imaging.

    Science.gov (United States)

    Han, Junwei; Chen, Changyuan; Shao, Ling; Hu, Xintao; Han, Jungong; Liu, Tianming

    2015-08-01

    Generally, various visual media are unequally memorable by the human brain. This paper looks into a new direction of modeling the memorability of video clips and automatically predicting how memorable they are by learning from brain functional magnetic resonance imaging (fMRI). We propose a novel computational framework by integrating the power of low-level audiovisual features and brain activity decoding via fMRI. Initially, a user study experiment is performed to create a ground truth database for measuring video memorability and a set of effective low-level audiovisual features is examined in this database. Then, human subjects' brain fMRI data are obtained when they are watching the video clips. The fMRI-derived features that convey the brain activity of memorizing videos are extracted using a universal brain reference system. Finally, due to the fact that fMRI scanning is expensive and time-consuming, a computational model is learned on our benchmark dataset with the objective of maximizing the correlation between the low-level audiovisual features and the fMRI-derived features using joint subspace learning. The learned model can then automatically predict the memorability of videos without fMRI scans. Evaluations on publically available image and video databases demonstrate the effectiveness of the proposed framework.

  5. A professional and cost effective digital video editing and image storage system for the operating room.

    Science.gov (United States)

    Scollato, A; Perrini, P; Benedetto, N; Di Lorenzo, N

    2007-06-01

    We propose an easy-to-construct digital video editing system ideal to produce video documentation and still images. A digital video editing system applicable to many video sources in the operating room is described in detail. The proposed system has proved easy to use and permits one to obtain videography quickly and easily. Mixing different streams of video input from all the devices in use in the operating room, the application of filters and effects produces a final, professional end-product. Recording on a DVD provides an inexpensive, portable and easy-to-use medium to store or re-edit or tape at a later time. From stored videography it is easy to extract high-quality, still images useful for teaching, presentations and publications. In conclusion digital videography and still photography can easily be recorded by the proposed system, producing high-quality video recording. The use of firewire ports provides good compatibility with next-generation hardware and software. The high standard of quality makes the proposed system one of the lowest priced products available today.

  6. Word2VisualVec: Image and Video to Sentence Matching by Visual Feature Prediction

    OpenAIRE

    Dong, Jianfeng; Li, Xirong; Snoek, Cees G. M.

    2016-01-01

    This paper strives to find the sentence best describing the content of an image or video. Different from existing works, which rely on a joint subspace for image / video to sentence matching, we propose to do so in a visual space only. We contribute Word2VisualVec, a deep neural network architecture that learns to predict a deep visual encoding of textual input based on sentence vectorization and a multi-layer perceptron. We thoroughly analyze its architectural design, by varying the sentence...

  7. An efficient image cryptosystem based on wolfram sequence and RNS

    African Journals Online (AJOL)

    In this paper we propose a novel encryption algorithm for digital images using the moduli set {2n+2, 2n+1, 2n}. The technique uses the Wolfram sequence for resizing, bitwise-XOR for pixel scrambling and modulus operation for pixel encoding. In the proposed scheme, a digital image is first segmented into many parts.

  8. Estimation of visual motion in image sequences

    DEFF Research Database (Denmark)

    Larsen, Rasmus

    1994-01-01

    are given. In particular we have investigated the use of smoothness of the second order derivatives, and the use of edge model and prior destributions for the field that favor discontinuities to characterize the motion field. A succesful implementation of a temporal interpolation in a sequence of weather...... of motion under an assumption of translatory motion has been considered. Furthermore we have described methods for quantifying the directional certainty with which we have measured the local displacement. A method based on local estimation of the spatio temporal orientation is generalized to give...

  9. Image-based temporal alignment of echocardiographic sequences

    Science.gov (United States)

    Danudibroto, Adriyana; Bersvendsen, Jørn; Mirea, Oana; Gerard, Olivier; D'hooge, Jan; Samset, Eigil

    2016-04-01

    Temporal alignment of echocardiographic sequences enables fair comparisons of multiple cardiac sequences by showing corresponding frames at given time points in the cardiac cycle. It is also essential for spatial registration of echo volumes where several acquisitions are combined for enhancement of image quality or forming larger field of view. In this study, three different image-based temporal alignment methods were investigated. First, a method based on dynamic time warping (DTW). Second, a spline-based method that optimized the similarity between temporal characteristic curves of the cardiac cycle using 1D cubic B-spline interpolation. Third, a method based on the spline-based method with piecewise modification. These methods were tested on in-vivo data sets of 19 echo sequences. For each sequence, the mitral valve opening (MVO) time was manually annotated. The results showed that the average MVO timing error for all methods are well under the time resolution of the sequences.

  10. Using statistical analysis and artificial intelligence tools for automatic assessment of video sequences

    Science.gov (United States)

    Ekobo Akoa, Brice; Simeu, Emmanuel; Lebowsky, Fritz

    2014-01-01

    This paper proposes two novel approaches to Video Quality Assessment (VQA). Both approaches attempt to develop video evaluation techniques capable of replacing human judgment when rating video quality in subjective experiments. The underlying study consists of selecting fundamental quality metrics based on Human Visual System (HVS) models and using artificial intelligence solutions as well as advanced statistical analysis. This new combination enables suitable video quality ratings while taking as input multiple quality metrics. The first method uses a neural network based machine learning process. The second method consists in evaluating the video quality assessment using non-linear regression model. The efficiency of the proposed methods is demonstrated by comparing their results with those of existing work done on synthetic video artifacts. The results obtained by each method are compared with scores from a database resulting from subjective experiments.

  11. Video and image retrieval beyond the cognitive level: the needs and possibilities

    Science.gov (United States)

    Hanjalic, Alan

    2001-01-01

    The worldwide research efforts in the are of image and video retrieval have concentrated so far on increasing the efficiency and reliability of extracting the elements of image and video semantics and so on improving the search and retrieval performance at the cognitive level of content abstraction. At this abstraction level, the user is searching for 'factual' or 'objective' content such as image showing a panorama of San Francisco, an outdoor or an indoor image, a broadcast news report on a defined topic, a movie dialog between the actors A and B or the parts of a basketball game showing fast breaks, steals and scores. These efforts, however, do not address the retrieval applications at the so-called affective level of content abstraction where the 'ground truth' is not strictly defined. Such applications are, for instance, those where subjectivity of the user plays the major role, e.g. the task of retrieving all images that the user 'likes most', and those that are based on 'recognizing emotions' in audiovisual data. Typical examples are searching for all images that 'radiate happiness', identifying all 'sad' movie fragments and looking for the 'romantic landscapes', 'sentimental' movie segments, 'movie highlights' or 'most exciting' moments of a sport event. This paper discusses the needs and possibilities for widening the current scope of research in the area of image and video search and retrieval in order to enable applications at the affective level of content abstraction.

  12. Fusion of intraoperative cone-beam CT and endoscopic video for image-guided procedures

    Science.gov (United States)

    Daly, M. J.; Chan, H.; Prisman, E.; Vescan, A.; Nithiananthan, S.; Qiu, J.; Weersink, R.; Irish, J. C.; Siewerdsen, J. H.

    2010-02-01

    Methods for accurate registration and fusion of intraoperative cone-beam CT (CBCT) with endoscopic video have been developed and integrated into a system for surgical guidance that accounts for intraoperative anatomical deformation and tissue excision. The system is based on a prototype mobile C-Arm for intraoperative CBCT that provides low-dose 3D image updates on demand with sub-mm spatial resolution and soft-tissue visibility, and also incorporates subsystems for real-time tracking and navigation, video endoscopy, deformable image registration of preoperative images and surgical plans, and 3D visualization software. The position and pose of the endoscope are geometrically registered to 3D CBCT images by way of real-time optical tracking (NDI Polaris) for rigid endoscopes (e.g., head and neck surgery), and electromagnetic tracking (NDI Aurora) for flexible endoscopes (e.g., bronchoscopes, colonoscopes). The intrinsic (focal length, principal point, non-linear distortion) and extrinsic (translation, rotation) parameters of the endoscopic camera are calibrated from images of a planar calibration checkerboard (2.5×2.5 mm2 squares) obtained at different perspectives. Video-CBCT registration enables a variety of 3D visualization options (e.g., oblique CBCT slices at the endoscope tip, augmentation of video with CBCT images and planning data, virtual reality representations of CBCT [surface renderings]), which can reveal anatomical structures not directly visible in the endoscopic view - e.g., critical structures obscured by blood or behind the visible anatomical surface. Video-CBCT fusion is evaluated in pre-clinical sinus and skull base surgical experiments, and is currently being incorporated into an ongoing prospective clinical trial in CBCT-guided head and neck surgery.

  13. Interactive segmentation of tongue contours in ultrasound video sequences using quality maps

    Science.gov (United States)

    Ghrenassia, Sarah; Ménard, Lucie; Laporte, Catherine

    2014-03-01

    Ultrasound (US) imaging is an effective and non invasive way of studying the tongue motions involved in normal and pathological speech, and the results of US studies are of interest for the development of new strategies in speech therapy. State-of-the-art tongue shape analysis techniques based on US images depend on semi-automated tongue segmentation and tracking techniques. Recent work has mostly focused on improving the accuracy of the tracking techniques themselves. However, occasional errors remain inevitable, regardless of the technique used, and the tongue tracking process must thus be supervised by a speech scientist who will correct these errors manually or semi-automatically. This paper proposes an interactive framework to facilitate this process. In this framework, the user is guided towards potentially problematic portions of the US image sequence by a segmentation quality map that is based on the normalized energy of an active contour model and automatically produced during tracking. When a problematic segmentation is identified, corrections to the segmented contour can be made on one image and propagated both forward and backward in the problematic subsequence, thereby improving the user experience. The interactive tools were tested in combination with two different tracking algorithms. Preliminary results illustrate the potential of the proposed framework, suggesting that the proposed framework generally improves user interaction time, with little change in segmentation repeatability.

  14. The ImageNet Shuffle: Reorganized Pre-training for Video Event Detection

    NARCIS (Netherlands)

    Mettes, P.; Koelma, D.C.; Snoek, C.G.M.

    2016-01-01

    This paper strives for video event detection using a representation learned from deep convolutional neural networks. Different from the leading approaches, who all learn from the 1,000 classes defined in the ImageNet Large Scale Visual Recognition Challenge, we investigate how to leverage the

  15. Video-rate two-photon excited fluorescence lifetime imaging system with interleaved digitization.

    Science.gov (United States)

    Dow, Ximeng Y; Sullivan, Shane Z; Muir, Ryan D; Simpson, Garth J

    2015-07-15

    A fast (up to video rate) two-photon excited fluorescence lifetime imaging system based on interleaved digitization is demonstrated. The system is compatible with existing beam-scanning microscopes with minor electronics and software modification. Proof-of-concept demonstrations were performed using laser dyes and biological tissue.

  16. Geometric Distortion in Image and Video Watermarking. Robustness and Perceptual Quality Impact

    NARCIS (Netherlands)

    Setyawan, I.

    2004-01-01

    The main focus of this thesis is the problem of geometric distortion in image and video watermarking. In this thesis we discuss the two aspects of the geometric distortion problem, namely the watermark desynchronization aspect and the perceptual quality assessment aspect. Furthermore, this thesis

  17. Class Energy Image Analysis for Video Sensor-Based Gait Recognition: A Review

    Directory of Open Access Journals (Sweden)

    Zhuowen Lv

    2015-01-01

    Full Text Available Gait is a unique perceptible biometric feature at larger distances, and the gait representation approach plays a key role in a video sensor-based gait recognition system. Class Energy Image is one of the most important gait representation methods based on appearance, which has received lots of attentions. In this paper, we reviewed the expressions and meanings of various Class Energy Image approaches, and analyzed the information in the Class Energy Images. Furthermore, the effectiveness and robustness of these approaches were compared on the benchmark gait databases. We outlined the research challenges and provided promising future directions for the field. To the best of our knowledge, this is the first review that focuses on Class Energy Image. It can provide a useful reference in the literature of video sensor-based gait representation approach.

  18. Class Energy Image Analysis for Video Sensor-Based Gait Recognition: A Review

    Science.gov (United States)

    Lv, Zhuowen; Xing, Xianglei; Wang, Kejun; Guan, Donghai

    2015-01-01

    Gait is a unique perceptible biometric feature at larger distances, and the gait representation approach plays a key role in a video sensor-based gait recognition system. Class Energy Image is one of the most important gait representation methods based on appearance, which has received lots of attentions. In this paper, we reviewed the expressions and meanings of various Class Energy Image approaches, and analyzed the information in the Class Energy Images. Furthermore, the effectiveness and robustness of these approaches were compared on the benchmark gait databases. We outlined the research challenges and provided promising future directions for the field. To the best of our knowledge, this is the first review that focuses on Class Energy Image. It can provide a useful reference in the literature of video sensor-based gait representation approach. PMID:25574935

  19. System and method for image registration of multiple video streams

    Energy Technology Data Exchange (ETDEWEB)

    Dillavou, Marcus W.; Shum, Phillip Corey; Guthrie, Baron L.; Shenai, Mahesh B.; Deaton, Drew Steven; May, Matthew Benton

    2018-02-06

    Provided herein are methods and systems for image registration from multiple sources. A method for image registration includes rendering a common field of interest that reflects a presence of a plurality of elements, wherein at least one of the elements is a remote element located remotely from another of the elements and updating the common field of interest such that the presence of the at least one of the elements is registered relative to another of the elements.

  20. Laser Imaging Video Camera Sees Through Fire, Fog, Smoke

    Science.gov (United States)

    2015-01-01

    Under a series of SBIR contracts with Langley Research Center, inventor Richard Billmers refined a prototype for a laser imaging camera capable of seeing through fire, fog, smoke, and other obscurants. Now, Canton, Ohio-based Laser Imaging through Obscurants (LITO) Technologies Inc. is demonstrating the technology as a perimeter security system at Glenn Research Center and planning its future use in aviation, shipping, emergency response, and other fields.

  1. Real-Depth imaging: a new (no glasses) 3D imaging technology with video/data projection applications

    Science.gov (United States)

    Dolgoff, Eugene

    1997-05-01

    Floating Images, Inc. has developed the software and hardware for anew, patent pending, 'floating 3D, off-the- screen-experience' display technology. This technology has the potential to become the next standard for home and arcade video games, computers, corporate presentations, Internet/Intranet viewing, and television. Current '3D Graphics' technologies are actually flat on screen. Floating Images technology actually produce images at different depths from any display, such as CRT and LCD, for television, computer, projection, and other formats. In addition, unlike stereoscopic 3D imaging, no glasses, headgear, or other viewing aids are used. And, unlike current autostereoscopic imaging technologies, there is virtually no restriction on where viewers can sit to view the images, with no 'bad' or 'dead' zones, flipping, or pseudoscopy. In addition to providing traditional depth cues such as perspective and background image occlusion, the new technology also provides both horizontal and vertical binocular parallax and accommodation which coincides with convergence. Since accommodation coincides with convergence, viewing these images doesn't produce headaches, fatigue, or eye-strain, regardless of how long they are viewed. The imagery must either be formatted for the Floating Images platform when written, or existing software can be reformatted without much difficult. The optical hardware system can be made to accommodate virtually any projection system to produce Floating Images for the Boardroom, video arcade, stage shows, or the classroom.

  2. Operational prediction of rip currents using numerical model and nearshore bathymetry from video images

    Science.gov (United States)

    Sembiring, L.; Van Ormondt, M.; Van Dongeren, A. R.; Roelvink, J. A.

    2017-07-01

    Rip currents are one of the most dangerous coastal hazards for swimmers. In order to minimize the risk, a coastal operational-process based-model system can be utilized in order to provide forecast of nearshore waves and currents that may endanger beach goers. In this paper, an operational model for rip current prediction by utilizing nearshore bathymetry obtained from video image technique is demonstrated. For the nearshore scale model, XBeach1 is used with which tidal currents, wave induced currents (including the effect of the wave groups) can be simulated simultaneously. Up-to-date bathymetry will be obtained using video images technique, cBathy 2. The system will be tested for the Egmond aan Zee beach, located in the northern part of the Dutch coastline. This paper will test the applicability of bathymetry obtained from video technique to be used as input for the numerical modelling system by comparing simulation results using surveyed bathymetry and model results using video bathymetry. Results show that the video technique is able to produce bathymetry converging towards the ground truth observations. This bathymetry validation will be followed by an example of operational forecasting type of simulation on predicting rip currents. Rip currents flow fields simulated over measured and modeled bathymetries are compared in order to assess the performance of the proposed forecast system.

  3. Subjective quality of video sequences rendered on LCD with local backlight dimming at different lighting conditions

    DEFF Research Database (Denmark)

    Mantel, Claire; Korhonen, Jari; Pedersen, Jesper Mørkhøj

    2015-01-01

    This paper focuses on the influence of ambient light on the perceived quality of videos displayed on Liquid Crystal Display (LCD) with local backlight dimming. A subjective test assessing the quality of videos with two backlight dimming methods and three lighting conditions, i.e. no light, low...

  4. Model-free 3D face shape reconstruction from video sequences

    NARCIS (Netherlands)

    van Dam, C.; Veldhuis, Raymond N.J.; Spreeuwers, Lieuwe Jan

    In forensic comparison of facial video data, often only the best quality frontal face frames are selected, and hence much video data is ignored. To improve 2D facial comparison for law enforcement and forensic investigation, we introduce a model-free 3D shape reconstruction algorithm based on 2D

  5. Landmark-based model-free 3D face shape reconstruction from video sequences

    NARCIS (Netherlands)

    van Dam, C.; Veldhuis, Raymond N.J.; Spreeuwers, Lieuwe Jan; Broemme, A.; Busch, C.

    2013-01-01

    In forensic comparison of facial video data, often only the best quality frontal face frames are selected, and hence potentially useful video data is ignored. To improve 2D facial comparison for law enforcement and forensic investigation, we introduce a model-free 3D shape reconstruction algorithm

  6. Extracting flat-field images from scene-based image sequences using phase correlation

    Energy Technology Data Exchange (ETDEWEB)

    Caron, James N., E-mail: Caron@RSImd.com [Research Support Instruments, 4325-B Forbes Boulevard, Lanham, Maryland 20706 (United States); Montes, Marcos J. [Naval Research Laboratory, Code 7231, 4555 Overlook Avenue, SW, Washington, DC 20375 (United States); Obermark, Jerome L. [Naval Research Laboratory, Code 8231, 4555 Overlook Avenue, SW, Washington, DC 20375 (United States)

    2016-06-15

    Flat-field image processing is an essential step in producing high-quality and radiometrically calibrated images. Flat-fielding corrects for variations in the gain of focal plane array electronics and unequal illumination from the system optics. Typically, a flat-field image is captured by imaging a radiometrically uniform surface. The flat-field image is normalized and removed from the images. There are circumstances, such as with remote sensing, where a flat-field image cannot be acquired in this manner. For these cases, we developed a phase-correlation method that allows the extraction of an effective flat-field image from a sequence of scene-based displaced images. The method uses sub-pixel phase correlation image registration to align the sequence to estimate the static scene. The scene is removed from sequence producing a sequence of misaligned flat-field images. An average flat-field image is derived from the realigned flat-field sequence.

  7. Extracting flat-field images from scene-based image sequences using phase correlation.

    Science.gov (United States)

    Caron, James N; Montes, Marcos J; Obermark, Jerome L

    2016-06-01

    Flat-field image processing is an essential step in producing high-quality and radiometrically calibrated images. Flat-fielding corrects for variations in the gain of focal plane array electronics and unequal illumination from the system optics. Typically, a flat-field image is captured by imaging a radiometrically uniform surface. The flat-field image is normalized and removed from the images. There are circumstances, such as with remote sensing, where a flat-field image cannot be acquired in this manner. For these cases, we developed a phase-correlation method that allows the extraction of an effective flat-field image from a sequence of scene-based displaced images. The method uses sub-pixel phase correlation image registration to align the sequence to estimate the static scene. The scene is removed from sequence producing a sequence of misaligned flat-field images. An average flat-field image is derived from the realigned flat-field sequence.

  8. Safety Assessment of Advanced Imaging Sequences I: Measurements.

    Science.gov (United States)

    Jensen, Jorgen Arendt; Rasmussen, Morten Fischer; Pihl, Michael Johannes; Holbek, Simon; Hoyos, Carlos Armando Villagómez; Bradway, David P; Stuart, Matthias Bo; Tomov, Borislav Gueorguiev

    2016-01-01

    A method for rapid measurement of intensities (I(spta)), mechanical index (MI), and probe surface temperature for any ultrasound scanning sequence is presented. It uses the scanner's sampling capability to give an accurate measurement of the whole imaging sequence for all emissions to yield the true distributions. The method is several orders of magnitude faster than approaches using an oscilloscope, and it also facilitates validating the emitted pressure field and the scanner's emission sequence software. It has been implemented using the experimental synthetic aperture real-time ultrasound system (SARUS) scanner and the Onda AIMS III intensity measurement system (Onda Corporation, Sunnyvale, CA, USA). Four different sequences have been measured: a fixed focus emission, a duplex sequence containing B-mode and flow emissions, a vector flow sequence with B-mode and flow emissions in 17 directions, and finally a SA duplex flow sequence. A BK8820e (BK Medical, Herlev, Denmark) convex array probe is used for the first three sequences and a BK8670 linear array probe for the SA sequence. The method is shown to give the same intensity values within 0.24% of the AIMS III Soniq 5.0 (Onda Corporation, Sunnyvale, CA, USA) commercial intensity measurement program. The approach can measure and store data for a full imaging sequence in 3.8-8.2 s per spatial position. Based on I(spta), MI, and probe surface temperature, the method gives the ability to determine whether a sequence is within U.S. FDA limits, or alternatively indicate how to scale it to be within limits.

  9. Low-complexity video encoding method for wireless image transmission in capsule endoscope.

    Science.gov (United States)

    Takizawa, Kenichi; Hamaguchi, Kiyoshi

    2010-01-01

    This paper presents a low-complexity video encoding method applicable for wireless image transmission in capsule endoscopes. This encoding method is based on Wyner-Ziv theory, in which side information available at a transmitter is treated as side information at its receiver. Therefore complex processes in video encoding, such as estimation of the motion vector, are moved to the receiver side, which has a larger-capacity battery. As a result, the encoding process is only to decimate coded original data through channel coding. We provide a performance evaluation for a low-density parity check (LDPC) coding method in the AWGN channel.

  10. Using smart phone video to supplement communication of radiology imaging in a neurosurgical unit: technical note.

    Science.gov (United States)

    Shivapathasundram, Ganeshwaran; Heckelmann, Michael; Sheridan, Mark

    2012-04-01

    The use of smart phones within medicine continues to grow at the same rate as mobile phone technology continues to evolve. One use of smart phones within medicine is in the transmission of radiological images to consultant neurosurgeons who are off-site in an emergency setting. In our unit, this has allowed quick, efficient, and safe communication between consultant neurosurgeon and trainees, aiding in rapid patient assessment and management in emergency situations. To describe a new means of smart phone technology use in the neurosurgical setting, where the video application of smart phones allows transfer of a whole series of patient neuroimaging via multimedia messaging service to off-site consultant neurosurgeons. METHOD/TECHNIQUE: Using the video application of smart phones, a 30-second video of an entire series of patient neuroimaging was transmitted to consultant neurosurgeons. With this information, combined with a clinical history, accurate management decisions were made. This technique has been used on a number of emergency situations in our unit to date. Thus far, the imaging received by consultants has been a very useful adjunct to the clinical information provided by the on-site trainee, and has helped expedite management of patients. While the aim should always be for the specialist neurosurgeon to review the imaging in person, in emergency settings, this is not always possible, and we feel that this technique of smart phone video is a very useful means for rapid communication with neurosurgeons.

  11. Comparison of Image Transform-Based Features for Visual Speech Recognition in Clean and Corrupted Videos

    Directory of Open Access Journals (Sweden)

    Ji Ming

    2008-03-01

    Full Text Available We present results of a study into the performance of a variety of different image transform-based feature types for speaker-independent visual speech recognition of isolated digits. This includes the first reported use of features extracted using a discrete curvelet transform. The study will show a comparison of some methods for selecting features of each feature type and show the relative benefits of both static and dynamic visual features. The performance of the features will be tested on both clean video data and also video data corrupted in a variety of ways to assess each feature type's robustness to potential real-world conditions. One of the test conditions involves a novel form of video corruption we call jitter which simulates camera and/or head movement during recording.

  12. Video outside versus video inside the web: do media setting and image size have an impact on the emotion-evoking potential of video?

    NARCIS (Netherlands)

    Verleur, R.; Verhagen, Pleunes Willem; Crawford, Margaret; Simonson, Michael; Lamboy, Carmen

    2001-01-01

    To explore the educational potential of video-evoked affective responses in a Web-based environment, the question was raised whether video in a Web-based environment is experienced differently from video in a traditional context. An experiment was conducted that studied the affect-evoking power of

  13. Research on hyperspectral dynamic scene and image sequence simulation

    Science.gov (United States)

    Sun, Dandan; Gao, Jiaobo; Sun, Kefeng; Hu, Yu; Li, Yu; Xie, Junhu; Zhang, Lei

    2016-10-01

    This paper presents a simulation method of hyper-spectral dynamic scene and image sequence for hyper-spectral equipment evaluation and target detection algorithm. Because of high spectral resolution, strong band continuity, anti-interference and other advantages, in recent years, hyper-spectral imaging technology has been rapidly developed and is widely used in many areas such as optoelectronic target detection, military defense and remote sensing systems. Digital imaging simulation, as a crucial part of hardware in loop simulation, can be applied to testing and evaluation hyper-spectral imaging equipment with lower development cost and shorter development period. Meanwhile, visual simulation can produce a lot of original image data under various conditions for hyper-spectral image feature extraction and classification algorithm. Based on radiation physic model and material characteristic parameters this paper proposes a generation method of digital scene. By building multiple sensor models under different bands and different bandwidths, hyper-spectral scenes in visible, MWIR, LWIR band, with spectral resolution 0.01μm, 0.05μm and 0.1μm have been simulated in this paper. The final dynamic scenes have high real-time and realistic, with frequency up to 100 HZ. By means of saving all the scene gray data in the same viewpoint image sequence is obtained. The analysis results show whether in the infrared band or the visible band, the grayscale variations of simulated hyper-spectral images are consistent with the theoretical analysis results.

  14. Bit Plane Coding based Steganography Technique for JPEG2000 Images and Videos

    Directory of Open Access Journals (Sweden)

    Geeta Kasana

    2016-02-01

    Full Text Available In this paper, a Bit Plane Coding (BPC based steganography technique for JPEG2000 images and Motion JPEG2000 video is proposed. Embedding in this technique is performed in the lowest significant bit planes of the wavelet coefficients of a cover image. In JPEG2000 standard, the number of bit planes of wavelet coefficients to be used in encoding is dependent on the compression rate and are used in Tier-2 process of JPEG2000. In the proposed technique, Tier-1 and Tier-2 processes of JPEG2000 and Motion JPEG2000 are executed twice on the encoder side to collect the information about the lowest bit planes of all code blocks of a cover image, which is utilized in embedding and transmitted to the decoder. After embedding secret data, Optimal Pixel Adjustment Process (OPAP is applied on stego images to enhance its visual quality. Experimental results show that proposed technique provides large embedding capacity and better visual quality of stego images than existing steganography techniques for JPEG2000 compressed images and videos. Extracted secret image is similar to the original secret image.

  15. Ultrafast video imaging of cell division from zebrafish egg using multimodal microscopic system

    Science.gov (United States)

    Lee, Sung-Ho; Jang, Bumjoon; Kim, Dong Hee; Park, Chang Hyun; Bae, Gyuri; Park, Seung Woo; Park, Seung-Han

    2017-07-01

    Unlike those of other ordinary laser scanning microscopies in the past, nonlinear optical laser scanning microscopy (SHG, THG microscopy) applied ultrafast laser technology which has high peak powers with relatively inexpensive, low-average-power. It short pulse nature reduces the ionization damage in organic molecules. And it enables us to take bright label-free images. In this study, we measured cell division of zebrafish egg with ultrafast video images using multimodal nonlinear optical microscope. The result shows in-vivo cell division label-free imaging with sub-cellular resolution.

  16. Face reconstruction from image sequences for forensic face comparison

    NARCIS (Netherlands)

    van Dam, C.; Veldhuis, Raymond N.J.; Spreeuwers, Lieuwe Jan

    2016-01-01

    The authors explore the possibilities of a dense model-free three-dimensional (3D) face reconstruction method, based on image sequences from a single camera, to improve the current state of forensic face comparison. They propose a new model-free 3D reconstruction method for faces, based on the

  17. Safety Assessment of Advanced Imaging Sequences II: Simulations

    DEFF Research Database (Denmark)

    Jensen, Jørgen Arendt

    2016-01-01

    An automatic approach for simulating the emitted pressure, intensity, and MI of advanced ultrasound imaging sequences is presented. It is based on a linear simulation of pressure fields using Field II, and it is hypothesized that linear simulation can attain the needed accuracy for predicting Mec...

  18. Modeling the Color Image and Video Quality on Liquid Crystal Displays with Backlight Dimming

    DEFF Research Database (Denmark)

    Korhonen, Jari; Mantel, Claire; Burini, Nino

    2013-01-01

    Objective image and video quality metrics focus mostly on the digital representation of the signal. However, the display characteristics are also essential for the overall Quality of Experience (QoE). In this paper, we use a model of a backlight dimming system for Liquid Crystal Display (LCD......) and show how the modeled image can be used as an input to quality assessment algorithms. For quality assessment, we propose an image quality metric, based on Peak Signal-to-Noise Ratio (PSNR) computation in the CIE L*a*b* color space. The metric takes luminance reduction, color distortion and loss...... of uniformity in the resulting image in consideration. Subjective evaluations of images generated using different backlight dimming algorithms and clipping strategies show that the proposed metric estimates the perceived image quality more accurately than conventional PSNR....

  19. Finding trajectories of feature points in a monocular image sequence.

    Science.gov (United States)

    Sethi, I K; Jain, R

    1987-01-01

    Identifying the same physical point in more than one image, the correspondence problem, is vital in motion analysis. Most research for establishing correspondence uses only two frames of a sequence to solve this problem. By using a sequence of frames, it is possible to exploit the fact that due to inertia the motion of an object cannot change instantaneously. By using smoothness of motion, it is possible to solve the correspondence problem for arbitrary motion of several nonrigid objects in a scene. We formulate the correspondence problem as an optimization problem and propose an iterative algorithm to find trajectories of points in a monocular image sequence. A modified form of this algorithm is useful in case of occlusion also. We demonstrate the efficacy of this approach considering synthetic, laboratory, and real scenes.

  20. The effects of video compression on acceptability of images for monitoring life sciences experiments

    Science.gov (United States)

    Haines, Richard F.; Chuang, Sherry L.

    1992-01-01

    Future manned space operations for Space Station Freedom will call for a variety of carefully planned multimedia digital communications, including full-frame-rate color video, to support remote operations of scientific experiments. This paper presents the results of an investigation to determine if video compression is a viable solution to transmission bandwidth constraints. It reports on the impact of different levels of compression and associated calculational parameters on image acceptability to investigators in life-sciences research at ARC. Three nonhuman life-sciences disciplines (plant, rodent, and primate biology) were selected for this study. A total of 33 subjects viewed experimental scenes in their own scientific disciplines. Ten plant scientists viewed still images of wheat stalks at various stages of growth. Each image was compressed to four different compression levels using the Joint Photographic Expert Group (JPEG) standard algorithm, and the images were presented in random order. Twelve and eleven staffmembers viewed 30-sec videotaped segments showing small rodents and a small primate, respectively. Each segment was repeated at four different compression levels in random order using an inverse cosine transform (ICT) algorithm. Each viewer made a series of subjective image-quality ratings. There was a significant difference in image ratings according to the type of scene viewed within disciplines; thus, ratings were scene dependent. Image (still and motion) acceptability does, in fact, vary according to compression level. The JPEG still-image-compression levels, even with the large range of 5:1 to 120:1 in this study, yielded equally high levels of acceptability. In contrast, the ICT algorithm for motion compression yielded a sharp decline in acceptability below 768 kb/sec. Therefore, if video compression is to be used as a solution for overcoming transmission bandwidth constraints, the effective management of the ratio and compression parameters

  1. Viral video: Live imaging of virus-host encounters

    Science.gov (United States)

    Son, Kwangmin; Guasto, Jeffrey S.; Cubillos-Ruiz, Andres; Chisholm, Sallie W.; Sullivan, Matthew B.; Stocker, Roman

    2014-11-01

    Viruses are non-motile infectious agents that rely on Brownian motion to encounter and subsequently adsorb to their hosts. Paradoxically, the viral adsorption rate is often reported to be larger than the theoretical limit imposed by the virus-host encounter rate, highlighting a major gap in the experimental quantification of virus-host interactions. Here we present the first direct quantification of the viral adsorption rate, obtained using live imaging of individual host cells and viruses for thousands of encounter events. The host-virus pair consisted of Prochlorococcus MED4, a 800 nm small non-motile bacterium that dominates photosynthesis in the oceans, and its virus PHM-2, a myovirus that has a 80 nm icosahedral capsid and a 200 nm long rigid tail. We simultaneously imaged hosts and viruses moving by Brownian motion using two-channel epifluorescent microscopy in a microfluidic device. This detailed quantification of viral transport yielded a 20-fold smaller adsorption efficiency than previously reported, indicating the need for a major revision in infection models for marine and likely other ecosystems.

  2. Automatic Polyp Detection in Pillcam Colon 2 Capsule Images and Videos: Preliminary Feasibility Report

    Directory of Open Access Journals (Sweden)

    Pedro N. Figueiredo

    2011-01-01

    Full Text Available Background. The aim of this work is to present an automatic colorectal polyp detection scheme for capsule endoscopy. Methods. PillCam COLON2 capsule-based images and videos were used in our study. The database consists of full exam videos from five patients. The algorithm is based on the assumption that the polyps show up as a protrusion in the captured images and is expressed by means of a P-value, defined by geometrical features. Results. Seventeen PillCam COLON2 capsule videos are included, containing frames with polyps, flat lesions, diverticula, bubbles, and trash liquids. Polyps larger than 1 cm express a P-value higher than 2000, and 80% of the polyps show a P-value higher than 500. Diverticula, bubbles, trash liquids, and flat lesions were correctly interpreted by the algorithm as nonprotruding images. Conclusions. These preliminary results suggest that the proposed geometry-based polyp detection scheme works well, not only by allowing the detection of polyps but also by differentiating them from nonprotruding images found in the films.

  3. Mission planning optimization of video satellite for ground multi-object staring imaging

    Science.gov (United States)

    Cui, Kaikai; Xiang, Junhua; Zhang, Yulin

    2018-03-01

    This study investigates the emergency scheduling problem of ground multi-object staring imaging for a single video satellite. In the proposed mission scenario, the ground objects require a specified duration of staring imaging by the video satellite. The planning horizon is not long, i.e., it is usually shorter than one orbit period. A binary decision variable and the imaging order are used as the design variables, and the total observation revenue combined with the influence of the total attitude maneuvering time is regarded as the optimization objective. Based on the constraints of the observation time windows, satellite attitude adjustment time, and satellite maneuverability, a constraint satisfaction mission planning model is established for ground object staring imaging by a single video satellite. Further, a modified ant colony optimization algorithm with tabu lists (Tabu-ACO) is designed to solve this problem. The proposed algorithm can fully exploit the intelligence and local search ability of ACO. Based on full consideration of the mission characteristics, the design of the tabu lists can reduce the search range of ACO and improve the algorithm efficiency significantly. The simulation results show that the proposed algorithm outperforms the conventional algorithm in terms of optimization performance, and it can obtain satisfactory scheduling results for the mission planning problem.

  4. Acquiring a dataset of labeled video images showing discomfort in demented elderly.

    Science.gov (United States)

    Bonroy, Bert; Schiepers, Pieter; Leysens, Greet; Miljkovic, Dragana; Wils, Maartje; De Maesschalck, Lieven; Quanten, Stijn; Triau, Eric; Exadaktylos, Vasileios; Berckmans, Daniel; Vanrumste, Bart

    2009-05-01

    One of the effects of late-stage dementia is the loss of the ability to communicate verbally. Patients become unable to call for help if they feel uncomfortable. The first objective of this article was to record facial expressions of bedridden demented elderly. For this purpose, we developed a video acquisition system (ViAS) that records synchronized video coming from two cameras. Each camera delivers uncompressed color images of 1,024 x 768 pixels, up to 30 frames per second. It is the first time that such a system has been placed in a patient's room. The second objective was to simultaneously label these video recordings with respect to discomfort expressions of the patients. Therefore, we developed a Digital Discomfort Labeling Tool (DDLT). This tool provides an easy-to-use software representation on a tablet PC of validated "paper" discomfort scales. With ViAS and DDLT, 80 different datasets were obtained of about 15 minutes of recordings. Approximately 80% of the recorded datasets delivered the labeled video recordings. The remainder were not usable due to under- or overexposed images and due to the patients being out of view as the system was not properly replaced after care. In one of 6 observed patients, nurses recognized a higher discomfort level that would not have been observed without the DDLT.

  5. Congruence analysis of point clouds from unstable stereo image sequences

    Directory of Open Access Journals (Sweden)

    C. Jepping

    2014-06-01

    Full Text Available This paper deals with the correction of exterior orientation parameters of stereo image sequences over deformed free-form surfaces without control points. Such imaging situation can occur, for example, during photogrammetric car crash test recordings where onboard high-speed stereo cameras are used to measure 3D surfaces. As a result of such measurements 3D point clouds of deformed surfaces are generated for a complete stereo sequence. The first objective of this research focusses on the development and investigation of methods for the detection of corresponding spatial and temporal tie points within the stereo image sequences (by stereo image matching and 3D point tracking that are robust enough for a reliable handling of occlusions and other disturbances that may occur. The second objective of this research is the analysis of object deformations in order to detect stable areas (congruence analysis. For this purpose a RANSAC-based method for congruence analysis has been developed. This process is based on the sequential transformation of randomly selected point groups from one epoch to another by using a 3D similarity transformation. The paper gives a detailed description of the congruence analysis. The approach has been tested successfully on synthetic and real image data.

  6. Optical flow estimation on image sequences with differently exposed frames

    Science.gov (United States)

    Bengtsson, Tomas; McKelvey, Tomas; Lindström, Konstantin

    2015-09-01

    Optical flow (OF) methods are used to estimate dense motion information between consecutive frames in image sequences. In addition to the specific OF estimation method itself, the quality of the input image sequence is of crucial importance to the quality of the resulting flow estimates. For instance, lack of texture in image frames caused by saturation of the camera sensor during exposure can significantly deteriorate the performance. An approach to avoid this negative effect is to use different camera settings when capturing the individual frames. We provide a framework for OF estimation on such sequences that contain differently exposed frames. Information from multiple frames are combined into a total cost functional such that the lack of an active data term for saturated image areas is avoided. Experimental results demonstrate that using alternate camera settings to capture the full dynamic range of an underlying scene can clearly improve the quality of flow estimates. When saturation of image data is significant, the proposed methods show superior performance in terms of lower endpoint errors of the flow vectors compared to a set of baseline methods. Furthermore, we provide some qualitative examples of how and when our method should be used.

  7. Innovative anisotropic phantoms for calibration of diffusion tensor imaging sequences.

    Science.gov (United States)

    Kłodowski, Krzysztof; Krzyżak, Artur Tadeusz

    2016-05-01

    The paper describes a novel type of anisotropic phantoms designed for b-matrix spatial distribution diffusion tensor imaging (BSD-DTI). Cubic plate anisotropic phantom, cylinder capillary phantom and water reference phantom are described as a complete set necessary for calibration, validation and normalization of BSD-DTI. An innovative design of the phantoms basing on enclosing the anisotropic cores in glass balls filled with liquid made for the first time possible BSD calibration with usage of echo planar imaging (EPI) sequence. Susceptibility artifacts prone to occur in EPI sequences were visibly reduced in the central region of the phantoms. The phantoms were designed for usage in a clinical scanner's head coil, but can be scaled for other coil or scanner types. The phantoms can be also used for a pre-calibration of imaging of other types of phantoms having more specific applications. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. Sequences for real-time magnetic particle imaging

    Directory of Open Access Journals (Sweden)

    Weber Matthias

    2015-09-01

    Full Text Available Magnetic Particle Imaging (MPI is a new imaging modality with the potential to be a new medical tool for angiographic diagnostics. It is capable of visualizing the spatial distribution of super-paramagnetic nanoparticles in high temporal and spatial resolution. Furthermore, the new spatial encoding scheme of a field free line (FFL promises a ten-fold higher sensitivity. So far, all know imaging devices featuring this new technique feature slow data acquisition and thus, are far away from real-time imaging capability. An actual real-time approach requires a complex field generator and an application of currents with very precise amplitude and phase. Here, we present the first implementation and calibration of a dynamic FFL field sequence enabling the acquisition of 50 MPI images per second in a mouse sized scanner.

  9. Estimation of Web video multiplicity

    Science.gov (United States)

    Cheung, SenChing S.; Zakhor, Avideh

    1999-12-01

    With ever more popularity of video web-publishing, many popular contents are being mirrored, reformatted, modified and republished, resulting in excessive content duplication. While such redundancy provides fault tolerance for continuous availability of information, it could potentially create problems for multimedia search engines in that the search results for a given query might become repetitious, and cluttered with a large number of duplicates. As such, developing techniques for detecting similarity and duplication is important to multimedia search engines. In addition, content providers might be interested in identifying duplicates of their content for legal, contractual or other business related reasons. In this paper, we propose an efficient algorithm called video signature to detect similar video sequences for large databases such as the web. The idea is to first form a 'signature' for each video sequence by selection a small number of its frames that are most similar to a number of randomly chosen seed images. Then the similarity between any tow video sequences can be reliably estimated by comparing their respective signatures. Using this method, we achieve 85 percent recall and precision ratios on a test database of 377 video sequences. As a proof of concept, we have applied our proposed algorithm to a collection of 1800 hours of video corresponding to around 45000 clips from the web. Our results indicate that, on average, every video in our collection from the web has around five similar copies.

  10. Body movement analysis during sleep for children with ADHD using video image processing.

    Science.gov (United States)

    Nakatani, Masahiro; Okada, Shima; Shimizu, Sachiko; Mohri, Ikuko; Ohno, Yuko; Taniike, Masako; Makikawa, Masaaki

    2013-01-01

    In recent years, the amount of children with sleep disorders that cause arousal during sleep or light sleep is increasing. Attention-deficit hyperactivity disorder (ADHD) is a cause of this sleep disorder; children with ADHD have frequent body movement during sleep. Therefore, we investigated the body movement during sleep of children with and without ADHD using video imaging. We analysed large gross body movements (GM) that occur and obtained the GM rate and the rest duration. There were differences between the body movements of children with ADHD and normally developed children. The children with ADHD moved frequently, so their rest duration was shorter than that of the normally developed children. Additionally, the rate of gross body movement indicated a significant difference in REM sleep (p video image processing.

  11. Super-Resolution Still and Video Reconstruction from MPEG Coded Video

    National Research Council Canada - National Science Library

    Altunbasak, Yucel

    2004-01-01

    Transform coding is a popular and effective compression method for both still images and video sequences, as is evident from its widespread use in international media coding standards such as MPEG, H.263 and JPEG...

  12. Radar image sequence analysis of inhomogeneous water surfaces

    Science.gov (United States)

    Seemann, Joerg; Senet, Christian M.; Dankert, Heiko; Hatten, Helge; Ziemer, Friedwart

    1999-10-01

    The radar backscatter from the ocean surface, called sea clutter, is modulated by the surface wave field. A method was developed to estimate the near-surface current, the water depth and calibrated surface wave spectra from nautical radar image sequences. The algorithm is based on the three- dimensional Fast Fourier Transformation (FFT) of the spatio- temporal sea clutter pattern in the wavenumber-frequency domain. The dispersion relation is used to define a filter to separate the spectral signal of the imaged waves from the background noise component caused by speckle noise. The signal-to-noise ratio (SNR) contains information about the significant wave height. The method has been proved to be reliable for the analysis of homogeneous water surfaces in offshore installations. Radar images are inhomogeneous because of the dependency of the image transfer function (ITF) on the azimuth angle between the wave propagation and the antenna viewing direction. The inhomogeneity of radar imaging is analyzed using image sequences of a homogeneous deep-water surface sampled by a ship-borne radar. Changing water depths in shallow-water regions induce horizontal gradients of the tidal current. Wave refraction occurs due to the spatial variability of the current and water depth. These areas cannot be investigated with the standard method. A new method, based on local wavenumber estimation with the multiple-signal classification (MUSIC) algorithm, is outlined. The MUSIC algorithm provides superior wavenumber resolution on local spatial scales. First results, retrieved from a radar image sequence taken from an installation at a coastal site, are presented.

  13. The importance of video editing in automated image analysis in studies of the cerebral cortex.

    Science.gov (United States)

    Terry, R D; Deteresa, R

    1982-03-01

    Editing of the video image in computerized image analysis is readily accomplished with the appropriate apparatus, but slows the assay very significantly. In dealing with the cerebral cortex, however video editing is of considerable importance in that cells are very often contiguous to one another or are partially superimposed, and this gives an erroneous measurement unless those cells are artificially separated. Also important is elimination of vascular cells from consideration by the automated counting apparatus. A third available mode of editing allows the filling-in of the cytoplasm of cell bodies which are not fully stained with sufficient intensity to be wholly detected. This study, which utilizes 23 samples, demonstrates that, in a given area of a histologic section of cerebral cortex, the number of small cells is greater and the number of large neurons is smaller with editing than without. In that not all cases follow this general pattern, inadequate editing may lead to significant errors on individual specimens as well as to the calculated mean. Video editing is therefore an essential part of the morphometric study of cerebral cortex by means of automated image analysis.

  14. Measurement of thigmomorphogenesis and gravitropism by non-intrusive computerized video image processing

    Science.gov (United States)

    Jaffe, M. J.

    1984-01-01

    A video image processing instrument, DARWIN (Digital Analyser of Resolvable Whole-pictures by Image Numeration), was developed. It was programmed to measure stem or root growth and bending, and coupled to a specially mounted video camera to be able to automatically generate growth and bending curves during gravitropism. The growth of the plant is recorded on a video casette recorder with a specially modified time lapse function. At the end of the experiment, DARWIN analyses the growth or movement and prints out bending and growth curves. This system was used to measure thigmomorphagenesis in light grown corn plants. If the plant is rubbed with an applied force load of 0.38 N., it grows faster than the unrubbed control, whereas 1.14 N. retards its growth. Image analysis shows that most of the change in the rate of growth is caused in the first hour after rubbing. When DARWIN was used to measure gravitropism in dark grown oat seedlings, it was found that the top side of the shoot contracts during the first hour of gravitational stimulus, whereas the bottom side begins to elongate after 10 to 15 minutes.

  15. Visual Recognition in RGB Images and Videos by Learning from RGB-D Data.

    Science.gov (United States)

    Li, Wen; Chen, Lin; Xu, Dong; Van Gool, Luc

    2017-08-02

    In this work, we propose a new framework for recognizing RGB images or videos by leveraging a set of labeled RGB-D data, in which the depth features can be additionally extracted from the depth images or videos. We formulate this task as a new unsupervised domain adaptation (UDA) problem, in which we aim to take advantage of the additional depth features in the source domain and also cope with the data distribution mismatch between the source and target domains. To handle the domain distribution mismatch, we propose to learn an optimal projection matrix to map the samples from both domains into a common subspace such that the domain distribution mismatch can be reduced. Moreover, we also propose different strategies to effectively utilize the additional depth features. To simultaneously cope with the above two issues, we formulate a unified learning framework called domain adaptation from multi-view to single-view (DAM2S). By defining various forms of regularizers in our DAM2S framework, different strategies can be readily incorporated to learn robust SVM classifiers for classifying the target samples. We conduct comprehensive experiments, which demonstrate the effectiveness of our proposed methods for recognizing RGB images and videos by learning from RGB-D data.

  16. The effect of music video clips on adolescent boys' body image, mood, and schema activation.

    Science.gov (United States)

    Mulgrew, Kate E; Volcevski-Kostas, Diana; Rendell, Peter G

    2014-01-01

    There is limited research that has examined experimentally the effects of muscular images on adolescent boys' body image, with no research specifically examining the effects of music television. The aim of the current study was to examine the effects of viewing muscular and attractive singers in music video clips on early, mid, and late adolescent boys' body image, mood, and schema activation. Participants were 180 boys in grade 7 (mean age = 12.73 years), grade 9 (mean age = 14.40 years) or grade 11 (mean age = 16.15 years) who completed pre- and post-test measures of mood and body satisfaction after viewing music videos containing male singers of muscular or average appearance. They also completed measures of schema activation and social comparison after viewing the clips. The results showed that the boys who viewed the muscular clips reported poorer upper body satisfaction, lower appearance satisfaction, lower happiness, and more depressive feelings compared to boys who viewed the clips depicting singers of average appearance. There was no evidence of increased appearance schema activation but the boys who viewed the muscular clips did report higher levels of social comparison to the singers. The results suggest that music video clips are a powerful form of media in conveying information about the male ideal body shape and that negative effects are found in boys as young as 12 years.

  17. Using image processing technology combined with decision tree algorithm in laryngeal video stroboscope automatic identification of common vocal fold diseases.

    Science.gov (United States)

    Jeffrey Kuo, Chung-Feng; Wang, Po-Chun; Chu, Yueng-Hsiang; Wang, Hsing-Won; Lai, Chun-Yu

    2013-10-01

    This study used the actual laryngeal video stroboscope videos taken by physicians in clinical practice as the samples for experimental analysis. The samples were dynamic vocal fold videos. Image processing technology was used to automatically capture the image of the largest glottal area from the video to obtain the physiological data of the vocal folds. In this study, an automatic vocal fold disease identification system was designed, which can obtain the physiological parameters for normal vocal folds, vocal paralysis and vocal nodules from image processing according to the pathological features. The decision tree algorithm was used as the classifier of the vocal fold diseases. The identification rate was 92.6%, and the identification rate with an image recognition improvement processing procedure after classification can be improved to 98.7%. Hence, the proposed system has value in clinical practices. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  18. Video transect images from the Hawaii Coral Reef Assessment and Monitoring Program (CRAMP): data from 2000 (NODC Accession 0000728)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset consists of video transect images (TIF files) from CRAMP surveys taken in 2000 at 23 sites, some of which had multiple depths. Estimates of substrate...

  19. Video transect images from the Hawaii Coral Reef Assessment and Monitoring Program (CRAMP): data from 2002 (NODC Accession 0000961)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset consists of video transect images (TIF files) from CRAMP surveys taken in 2002 at 23 sites, some of which had multiple depths. Estimates of substrate...

  20. Video transect images from the Hawaii Coral Reef Assessment and Monitoring Program (CRAMP): data from year 1999 (NODC Accession 0000671)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset consists of video transect images (JPEG files) from CRAMP surveys taken in 1999 at 26 sites, some of which had multiple depths. Estimates of substrate...

  1. Video Transect Images from the Hawaii Coral Reef Assessment and Monitoring Program (CRAMP): Data from 2000 (NODC Accession 0000728)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset consists of video transect images (TIF files) from CRAMP surveys taken in 2000 at 23 sites, some of which had multiple depths. Estimates of substrate...

  2. Video Transect Images from the Hawaii Coral Reef Assessment and Monitoring Program (CRAMP):Data from 2003 (NODC Accession 0001732)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset consists of video transect images (TIF files) from CRAMP surveys taken in 2003 at 15 sites, some of which had multiple depths. Estimates of substrate...

  3. Video Transect Images from the Hawaii Coral Reef Assessment and Monitoring Program (CRAMP): Data from 2003 (NODC Accession 0001732)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset consists of video transect images (TIF files) from CRAMP surveys taken in 2003 at 15 sites, some of which had multiple depths. Estimates of substrate...

  4. Video Transect Images (1999) from the Hawaii Coral Reef Assessment and Monitoring Program (CRAMP) (NODC Accession 0000671)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset consists of video transect images (JPEG files) from CRAMP surveys taken in 1999 at 26 sites, some of which had multiple depths. Estimates of substrate...

  5. Video Transect Images from the Hawaii Coral Reef Assessment and Monitoring Program (CRAMP): Data from 2002 (NODC Accession 0000961)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset consists of video transect images (TIF files) from CRAMP surveys taken in 2002 at 23 sites, some of which had multiple depths. Estimates of substrate...

  6. Artifact reduction of compressed images and video combining adaptive fuzzy filtering and directional anisotropic diffusion

    DEFF Research Database (Denmark)

    Nadernejad, Ehsan; Forchhammer, Søren; Korhonen, Jari

    2011-01-01

    and ringing artifacts, we have applied directional anisotropic diffusion. Besides that, the selection of the adaptive threshold parameter for the diffusion coefficient has also improved the performance of the algorithm. Experimental results on JPEG compressed images as well as MJPEG and H.264 compressed......Fuzzy filtering is one of the recently developed methods for reducing distortion in compressed images and video. In this paper, we combine the powerful anisotropic diffusion equations with fuzzy filtering in order to reduce the impact of artifacts. Based on the directional nature of the blocking...

  7. Concurrent Calculations on Reconfigurable Logic Devices Applied to the Analysis of Video Images

    Directory of Open Access Journals (Sweden)

    Sergio R. Geninatti

    2010-01-01

    Full Text Available This paper presents the design and implementation on FPGA devices of an algorithm for computing similarities between neighboring frames in a video sequence using luminance information. By taking advantage of the well-known flexibility of Reconfigurable Logic Devices, we have designed a hardware implementation of the algorithm used in video segmentation and indexing. The experimental results show the tradeoff between concurrent sequential resources and the functional blocks needed to achieve maximum operational speed while achieving minimum silicon area usage. To evaluate system efficiency, we compare the performance of the hardware solution to that of calculations done via software using general-purpose processors with and without an SIMD instruction set.

  8. Comparison of ultrasound imaging and video otoscopy with cross-sectional imaging for the diagnosis of canine otitis media.

    Science.gov (United States)

    Classen, J; Bruehschwein, A; Meyer-Lindenberg, A; Mueller, R S

    2016-11-01

    Ultrasound imaging (US) of the tympanic bulla (TB) for diagnosis of canine otitis media (OM) is less expensive and less invasive than cross-sectional imaging techniques including computed tomography (CT) and magnetic resonance imaging (MRI). Video otoscopy (VO) is used to clean inflamed ears. The objective of this study was to investigate the diagnostic value of US and VO in OM using cross-sectional imaging as the reference standard. Client owned dogs with clinical signs of OE and/or OM were recruited for the study. Physical, neurological, otoscopic and otic cytological examinations were performed on each dog and both TB were evaluated using US with an 8 MHz micro convex probe, cross-sectional imaging (CT or MRI) and VO. Of 32 dogs enrolled, 24 had chronic otitis externa (OE; five also had clinical signs of OM), four had acute OE without clinical signs of OM, and four had OM without OE. Ultrasound imaging was positive in three of 14 ears, with OM identified on cross-sectional imaging. One US was false positive. Sensitivity, specificity, positive and negative predictive values and accuracy of US were 21%, 98%, 75%, 81% and 81%, respectively. The corresponding values of VO were 91%, 98%, 91%, 98% and 97%, respectively. Video otoscopy could not identify OM in one case, while in another case, although the tympanum was ruptured, the CT was negative. Ultrasound imaging should not replace cross-sectional imaging for the diagnosis of canine OM, but can be helpful, and VO was much more reliable than US. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. High-Performance Motion Estimation for Image Sensors with Video Compression

    Directory of Open Access Journals (Sweden)

    Weizhi Xu

    2015-08-01

    Full Text Available It is important to reduce the time cost of video compression for image sensors in video sensor network. Motion estimation (ME is the most time-consuming part in video compression. Previous work on ME exploited intra-frame data reuse in a reference frame to improve the time efficiency but neglected inter-frame data reuse. We propose a novel inter-frame data reuse scheme which can exploit both intra-frame and inter-frame data reuse for ME in video compression (VC-ME. Pixels of reconstructed frames are kept on-chip until they are used by the next current frame to avoid off-chip memory access. On-chip buffers with smart schedules of data access are designed to perform the new data reuse scheme. Three levels of the proposed inter-frame data reuse scheme are presented and analyzed. They give different choices with tradeoff between off-chip bandwidth requirement and on-chip memory size. All three levels have better data reuse efficiency than their intra-frame counterparts, so off-chip memory traffic is reduced effectively. Comparing the new inter-frame data reuse scheme with the traditional intra-frame data reuse scheme, the memory traffic can be reduced by 50% for VC-ME.

  10. High-Performance Motion Estimation for Image Sensors with Video Compression.

    Science.gov (United States)

    Xu, Weizhi; Yin, Shouyi; Liu, Leibo; Liu, Zhiyong; Wei, Shaojun

    2015-08-21

    It is important to reduce the time cost of video compression for image sensors in video sensor network. Motion estimation (ME) is the most time-consuming part in video compression. Previous work on ME exploited intra-frame data reuse in a reference frame to improve the time efficiency but neglected inter-frame data reuse. We propose a novel inter-frame data reuse scheme which can exploit both intra-frame and inter-frame data reuse for ME in video compression (VC-ME). Pixels of reconstructed frames are kept on-chip until they are used by the next current frame to avoid off-chip memory access. On-chip buffers with smart schedules of data access are designed to perform the new data reuse scheme. Three levels of the proposed inter-frame data reuse scheme are presented and analyzed. They give different choices with tradeoff between off-chip bandwidth requirement and on-chip memory size. All three levels have better data reuse efficiency than their intra-frame counterparts, so off-chip memory traffic is reduced effectively. Comparing the new inter-frame data reuse scheme with the traditional intra-frame data reuse scheme, the memory traffic can be reduced by 50% for VC-ME.

  11. A real-time remote video streaming platform for ultrasound imaging.

    Science.gov (United States)

    Ahmadi, Mehdi; Gross, Warren J; Kadoury, Samuel

    2016-08-01

    Ultrasound is a viable imaging technology in remote and resources-limited areas. Ultrasonography is a user-dependent skill which depends on a high degree of training and hands-on experience. However, there is a limited number of skillful sonographers located in remote areas. In this work, we aim to develop a real-time video streaming platform which allows specialist physicians to remotely monitor ultrasound exams. To this end, an ultrasound stream is captured and transmitted through a wireless network into remote computers, smart-phones and tablets. In addition, the system is equipped with a camera to track the position of the ultrasound probe. The main advantage of our work is using an open source platform for video streaming which gives us more control over streaming parameters than the available commercial products. The transmission delays of the system are evaluated for several ultrasound video resolutions and the results show that ultrasound videos close to the high-definition (HD) resolution can be received and displayed on an Android tablet with the delay of 0.5 seconds which is acceptable for accurate real-time diagnosis.

  12. [Superimpose of images by appending two simple video amplifier circuits to color television (author's transl)].

    Science.gov (United States)

    Kojima, K; Hiraki, T; Koshida, K; Maekawa, R; Hisada, K

    1979-09-15

    Images are very useful to obtain diagnostic informations in medical fields. Also by superimposing two or three images obtained from the same patient, various informations, for example a degree of overlapping and anatomical land mark, which can not be found in only one image, can be often found. In this paper characteristics of our trial color television system for the purpose of superimposing X-ray images and/or radionuclide images are described. This color television system, superimposing two images in each different color consists of two monochromatic vidicon cameras and 20 inches conventional color television in which only two simple video amplifier circuits are added. Signals from vidicon cameras are amplified about 40 dB and are directly applied to cathode terminals of color CRT in the television. This system is very simple and economical color displays, and enhance a degree of overlapping and displacement between images. As one of typical clinical applications, pancreas images were superimposed in color by this method. As a result, size and position of pancreas was enhanced. Also X-ray image and radionuclide image were superimposed to find exactly the position of tumors. Furthermore this system was very useful for color display of multinuclides scintigraphy.

  13. Availability and performance of image/video-based vital signs monitoring methods: a systematic review protocol.

    Science.gov (United States)

    Harford, Mirae; Catherall, Jacqueline; Gerry, Stephen; Young, Duncan; Watkinson, Peter

    2017-10-25

    For many vital signs, monitoring methods require contact with the patient and/or are invasive in nature. There is increasing interest in developing still and video image-guided monitoring methods that are non-contact and non-invasive. We will undertake a systematic review of still and video image-based monitoring methods. We will perform searches in multiple databases which include MEDLINE, Embase, CINAHL, Cochrane library, IEEE Xplore and ACM Digital Library. We will use OpenGrey and Google searches to access unpublished or commercial data. We will not use language or publication date restrictions. The primary goal is to summarise current image-based vital signs monitoring methods, limited to heart rate, respiratory rate, oxygen saturations and blood pressure. Of particular interest will be the effectiveness of image-based methods compared to reference devices. Other outcomes of interest include the quality of the method comparison studies with respect to published reporting guidelines, any limitations of non-contact non-invasive technology and application in different populations. To the best of our knowledge, this is the first systematic review of image-based non-contact methods of vital signs monitoring. Synthesis of currently available technology will facilitate future research in this highly topical area. PROSPERO CRD42016029167.

  14. Availability and performance of image/video-based vital signs monitoring methods: a systematic review protocol

    Directory of Open Access Journals (Sweden)

    Mirae Harford

    2017-10-01

    Full Text Available Abstract Background For many vital signs, monitoring methods require contact with the patient and/or are invasive in nature. There is increasing interest in developing still and video image-guided monitoring methods that are non-contact and non-invasive. We will undertake a systematic review of still and video image-based monitoring methods. Methods We will perform searches in multiple databases which include MEDLINE, Embase, CINAHL, Cochrane library, IEEE Xplore and ACM Digital Library. We will use OpenGrey and Google searches to access unpublished or commercial data. We will not use language or publication date restrictions. The primary goal is to summarise current image-based vital signs monitoring methods, limited to heart rate, respiratory rate, oxygen saturations and blood pressure. Of particular interest will be the effectiveness of image-based methods compared to reference devices. Other outcomes of interest include the quality of the method comparison studies with respect to published reporting guidelines, any limitations of non-contact non-invasive technology and application in different populations. Discussion To the best of our knowledge, this is the first systematic review of image-based non-contact methods of vital signs monitoring. Synthesis of currently available technology will facilitate future research in this highly topical area. Systematic review registration PROSPERO CRD42016029167

  15. A unified framework for capturing facial images in video surveillance systems using cooperative camera system

    Science.gov (United States)

    Chan, Fai; Moon, Yiu-Sang; Chen, Jiansheng; Ma, Yiu-Kwan; Tsang, Wai-Hung; Fu, Kah-Kuen

    2008-04-01

    Low resolution and un-sharp facial images are always captured from surveillance videos because of long human-camera distance and human movements. Previous works addressed this problem by using an active camera to capture close-up facial images without considering human movements and mechanical delays of the active camera. In this paper, we proposed a unified framework to capture facial images in video surveillance systems by using one static and active camera in a cooperative manner. Human faces are first located by a skin-color based real-time face detection algorithm. A stereo camera model is also employed to approximate human face location and his/her velocity with respect to the active camera. Given the mechanical delays of the active camera, the position of a target face with a given delay can be estimated using a Human-Camera Synchronization Model. By controlling the active camera with corresponding amount of pan, tilt, and zoom, a clear close-up facial image of a moving human can be captured then. We built the proposed system in an 8.4-meter indoor corridor. Results show that the proposed stereo camera configuration can locate faces with average error of 3%. In addition, it is capable of capturing facial images of a walking human clearly in first instance in 90% of the test cases.

  16. Segmentation of medical image sequence by parallel active contour.

    Science.gov (United States)

    Fekir, Abdelkader; Benamrane, Nacéra

    2011-01-01

    This paper presents an original approach for detecting and tracking of objects in medical image sequence. We propose a multi-agent system (MAS) based on NetLogo platform for implementing parametric contour active model or snake. In NetLogo, mobile agents (turtles) move over a grid of stationary agents (patches). In our proposed MAS, each mobile agent represents a point of snake (snaxel) and it minimizes, in parallel with other turtles, the energy functional attached to its snaxel. Then, these turtles move over the image represented by a grid of patches. The set of these agents is supervised by Observer, the NetLogo global agent. In addition, Observer loads successively the frames of sequence and initializes the turtles in the first frame. The efficiency of our system is shown through some experimental results.

  17. Analysis of the cryptography security and steganography in images sequences

    OpenAIRE

    Fábio Borges de Oliveira

    2007-01-01

    Information security is being considered of great importance to the private and governamental institutions. For this reason, we opted to conduct a study of security in this dissertation. We started with an introduction to the information theory, and then we proposed a new kind of Perfect Secrecy cryptographic and finally made a study of steganography in an image sequence, in which we suggest a more aggressive steganography in coefficients of the discrete cosine transform. A segurança da in...

  18. A Video Rate Confocal Laser Beam Scanning Light Microscope Using An Image Dissector

    Science.gov (United States)

    Goldstein, Seth R.; Hubin, Thomas; Rosenthal, Scott; Washburn, Clayton

    1989-12-01

    A video rate confocal reflected light microscope with no moving parts has been developed. Return light from an acousto-optically raster scanned laser beam is imaged from the microscope stage onto the photocathode of an Image Dissector Tube (IDT). Confocal operation is achieved by appropriately raster scanning with the IDT x and y deflection coils so as to continuously "sample" that portion of the photocathode that is being instantaneously illuminated by the return image of the scanning laser spot. Optimum IDT scan parameters and geometric distortion correction parameters are determined under computer control within seconds and are then continuously applied to insure system alignment. The system is operational and reflected light images from a variety of objects have been obtained. The operating principle can be extended to fluorescence and transmission microscopy.

  19. Venus in motion: An animated video catalog of Pioneer Venus Orbiter Cloud Photopolarimeter images

    Science.gov (United States)

    Limaye, Sanjay S.

    1992-01-01

    Images of Venus acquired by the Pioneer Venus Orbiter Cloud Photopolarimeter (OCPP) during the 1982 opportunity have been utilized to create a short video summary of the data. The raw roll by roll images were first navigated using the spacecraft attitude and orbit information along with the CPP instrument pointing information. The limb darkening introduced by the variation of solar illumination geometry and the viewing angle was then modelled and removed. The images were then projected to simulate a view obtained from a fixed perspective with the observer at 10 Venus radii away and located above a Venus latitude of 30 degrees south and a longitude 60 degrees west. A total of 156 images from the 1982 opportunity have been animated at different dwell rates.

  20. Perceptual distortion measure for edgelike artifacts in image sequences

    Science.gov (United States)

    Yeh, Edmund M.; Kokaram, Anil C.; Kingsbury, Nick G.

    1998-07-01

    This paper presents an objective perceptual distortion measure quantifying the visibility of edge-like blocking artifacts in coded image sequences resulting from popular transform coding techniques. The prime motivation for this work is the awareness that properties of the human visual system should be central to the design and evaluation of image coding algorithms. The perceptual metric is the output of a visual model incorporating both the spatial and temporal characteristics of the visual system. Parameters of the model are based on results from a number of visual experiments in which sensitivities to simulated blocking artifacts were measured under various spatio-temporal background conditions. The visual model takes a pair of original and distorted sequences as inputs. Distortions are calculated along the vertical and horizontal directions. Visibility dependencies on spatial, temporal and motion activities of the background are incorporated using linear filtering and motion estimation. Pixel-based distortions are combined over local spatial and temporal regions to generate an overall distortion measure for each orientation. The final model output is the sum of the vertical and horizontal distortion measures. The model was applied to coded image sequences and the resulting distortion measures were compared to outcomes of subjective ranking tests. Results indicate that the perceptual distortion measure agrees well with human evaluation.

  1. Towards Realising Secure and Efficient Image and Video Processing Applications on Quantum Computers

    Directory of Open Access Journals (Sweden)

    Abdullah M. Iliyasu

    2013-07-01

    Full Text Available Exploiting the promise of security and efficiency that quantum computing offers, the basic foundations leading to commercial applications for quantum image processing are proposed. Two mathematical frameworks and algorithms to accomplish the watermarking of quantum images, authentication of ownership of already watermarked images and recovery of their unmarked versions on quantum computers are proposed. Encoding the images as 2n-sized normalised Flexible Representation of Quantum Images (FRQI states, with n-qubits and 1-qubit dedicated to capturing the respective information about the colour and position of every pixel in the image respectively, the proposed algorithms utilise the flexibility inherent to the FRQI representation, in order to confine the transformations on an image to any predetermined chromatic or spatial (or a combination of both content of the image as dictated by the watermark embedding, authentication or recovery circuits. Furthermore, by adopting an apt generalisation of the criteria required to realise physical quantum computing hardware, three standalone components that make up the framework to prepare, manipulate and recover the various contents required to represent and produce movies on quantum computers are also proposed. Each of the algorithms and the mathematical foundations for their execution were simulated using classical (i.e., conventional or non-quantum computing resources, and their results were analysed alongside other longstanding classical computing equivalents. The work presented here, combined together with the extensions suggested, provide the basic foundations towards effectuating secure and efficient classical-like image and video processing applications on the quantum-computing framework.

  2. VORTEX: video retrieval and tracking from compressed multimedia databases--template matching from MPEG-2 video compression standard

    Science.gov (United States)

    Schonfeld, Dan; Lelescu, Dan

    1998-10-01

    In this paper, a novel visual search engine for video retrieval and tracking from compressed multimedia databases is proposed. Our approach exploits the structure of video compression standards in order to perform object matching directly on the compressed video data. This is achieved by utilizing motion compensation--a critical prediction filter embedded in video compression standards--to estimate and interpolate the desired method for template matching. Motion analysis is used to implement fast tracking of objects of interest on the compressed video data. Being presented with a query in the form of template images of objects, the system operates on the compressed video in order to find the images or video sequences where those objects are presented and their positions in the image. This in turn enables the retrieval and display of the query-relevant sequences.

  3. Analysis of Decorrelation Transform Gain for Uncoded Wireless Image and Video Communication.

    Science.gov (United States)

    Ruiqin Xiong; Feng Wu; Jizheng Xu; Xiaopeng Fan; Chong Luo; Wen Gao

    2016-04-01

    An uncoded transmission scheme called SoftCast has recently shown great potential for wireless video transmission. Unlike conventional approaches, SoftCast processes input images only by a series of transformations and modulates the coefficients directly to a dense constellation for transmission. The transmission is uncoded and lossy in nature, with its noise level commensurate with the channel condition. This paper presents a theoretical analysis for an uncoded visual communication, focusing on developing a quantitative measurements for the efficiency of decorrelation transform in a generalized uncoded transmission framework. Our analysis reveals that the energy distribution among signal elements is critical for the efficiency of uncoded transmission. A decorrelation transform can potentially bring a significant performance gain by boosting the energy diversity in signal representation. Numerical results on Markov random process and real image and video signals are reported to evaluate the performance gain of using different transforms in uncoded transmission. The analysis presented in this paper is verified by simulated SoftCast transmissions. This provide guidelines for designing efficient uncoded video transmission schemes.

  4. Validation of a pediatric vocal fold nodule rating scale based on digital video images.

    Science.gov (United States)

    Nuss, Roger C; Ward, Jessica; Recko, Thomas; Huang, Lin; Woodnorth, Geralyn Harvey

    2012-01-01

    We sought to create a validated scale of vocal fold nodules in children, based on digital video clips obtained during diagnostic fiberoptic laryngoscopy. We developed a 4-point grading scale of vocal fold nodules in children, based upon short digital video clips. A tutorial for use of the scale, including schematic drawings of nodules, static images, and 10-second video clips, was presented to 36 clinicians with various levels of experience. The clinicians then reviewed 40 short digital video samples from pediatric patients evaluated in a voice clinic and rated the nodule size. Statistical analysis of the ratings provided inter-rater reliability scores. Thirty-six clinicians with various levels of experience rated a total of 40 short video clips. The ratings of experienced raters (14 pediatric otolaryngology attending physicians and pediatric otolaryngology fellows) were compared with those of inexperienced raters (22 nurses, medical students, otolaryngology residents, physician assistants, and pediatric speech-language pathologists). The overall intraclass correlation coefficient for the ratings of nodule size was quite good (0.62; 95% confidence interval, 0.52 to 0.74). The p value for experienced raters versus inexperienced raters was 0.1345, indicating no statistically significant difference in the ratings by these two groups. The intraclass correlation coefficient for intra-rater reliability was very high (0.89). The use of a dynamic scale of pediatric vocal fold nodule size most realistically represents the clinical assessment of nodules during an office visit. The results of this study show a high level of agreement between experienced and inexperienced raters. This scale can be used with a high level of reliability by clinicians with various levels of experience. A validated grading scale will help to assess long-term outcomes of pediatric patients with vocal fold nodules.

  5. Non-rigid consistent registration of 2D image sequences

    Energy Technology Data Exchange (ETDEWEB)

    Arganda-Carreras, I; Sorzano, C O S; Marabini, R; Carazo, J M [Biocomputing Unit, National Centre for Biotechnology, CSIC, Darwin 3, Universidad Autonoma de Madrid, 28049 Madrid (Spain); Thevenaz, P [Biomedical Imaging Group, Ecole polytechnique federale de Lausanne (EPFL) (Switzerland); Munoz-Barrutia, A; Ortiz-de Solorzano, C [Cancer Imaging Laboratory, Centre for Applied Medical Research, University of Navarra, Pamplona (Spain); Kybic, J, E-mail: iarganda@cnb.csic.e [Center for Machine Perception, Czech Technical University, Prague (Czech Republic)

    2010-10-21

    We present a novel algorithm for the registration of 2D image sequences that combines the principles of multiresolution B-spline-based elastic registration and those of bidirectional consistent registration. In our method, consecutive triples of images are iteratively registered to gradually extend the information through the set of images of the entire sequence. The intermediate results are reused for the registration of the following triple. We choose to interpolate the images and model the deformation fields using B-spline multiresolution pyramids. Novel boundary conditions are introduced to better characterize the deformations at the boundaries. In the experimental section, we quantitatively show that our method recovers from barrel/pincushion and fish-eye deformations with subpixel error. Moreover, it is more robust against outliers-occasional strong noise and large rotations-than the state-of-the-art methods. Finally, we show that our method can be used to realign series of histological serial sections, which are often heavily distorted due to folding and tearing of the tissues.

  6. Non-rigid consistent registration of 2D image sequences

    Science.gov (United States)

    Arganda-Carreras, I.; Sorzano, C. O. S.; Thévenaz, P.; Muñoz-Barrutia, A.; Kybic, J.; Marabini, R.; Carazo, J. M.; Ortiz-de Solorzano, C.

    2010-10-01

    We present a novel algorithm for the registration of 2D image sequences that combines the principles of multiresolution B-spline-based elastic registration and those of bidirectional consistent registration. In our method, consecutive triples of images are iteratively registered to gradually extend the information through the set of images of the entire sequence. The intermediate results are reused for the registration of the following triple. We choose to interpolate the images and model the deformation fields using B-spline multiresolution pyramids. Novel boundary conditions are introduced to better characterize the deformations at the boundaries. In the experimental section, we quantitatively show that our method recovers from barrel/pincushion and fish-eye deformations with subpixel error. Moreover, it is more robust against outliers—occasional strong noise and large rotations—than the state-of-the-art methods. Finally, we show that our method can be used to realign series of histological serial sections, which are often heavily distorted due to folding and tearing of the tissues.

  7. A flexible software architecture for scalable real-time image and video processing applications

    Science.gov (United States)

    Usamentiaga, Rubén; Molleda, Julio; García, Daniel F.; Bulnes, Francisco G.

    2012-06-01

    Real-time image and video processing applications require skilled architects, and recent trends in the hardware platform make the design and implementation of these applications increasingly complex. Many frameworks and libraries have been proposed or commercialized to simplify the design and tuning of real-time image processing applications. However, they tend to lack flexibility because they are normally oriented towards particular types of applications, or they impose specific data processing models such as the pipeline. Other issues include large memory footprints, difficulty for reuse and inefficient execution on multicore processors. This paper presents a novel software architecture for real-time image and video processing applications which addresses these issues. The architecture is divided into three layers: the platform abstraction layer, the messaging layer, and the application layer. The platform abstraction layer provides a high level application programming interface for the rest of the architecture. The messaging layer provides a message passing interface based on a dynamic publish/subscribe pattern. A topic-based filtering in which messages are published to topics is used to route the messages from the publishers to the subscribers interested in a particular type of messages. The application layer provides a repository for reusable application modules designed for real-time image and video processing applications. These modules, which include acquisition, visualization, communication, user interface and data processing modules, take advantage of the power of other well-known libraries such as OpenCV, Intel IPP, or CUDA. Finally, we present different prototypes and applications to show the possibilities of the proposed architecture.

  8. Interaction between High-Level and Low-Level Image Analysis for Semantic Video Object Extraction

    Directory of Open Access Journals (Sweden)

    Ebrahimi Touradj

    2004-01-01

    Full Text Available The task of extracting a semantic video object is split into two subproblems, namely, object segmentation and region segmentation. Object segmentation relies on a priori assumptions, whereas region segmentation is data-driven and can be solved in an automatic manner. These two subproblems are not mutually independent, and they can benefit from interactions with each other. In this paper, a framework for such interaction is formulated. This representation scheme based on region segmentation and semantic segmentation is compatible with the view that image analysis and scene understanding problems can be decomposed into low-level and high-level tasks. Low-level tasks pertain to region-oriented processing, whereas the high-level tasks are closely related to object-level processing. This approach emulates the human visual system: what one “sees” in a scene depends on the scene itself (region segmentation as well as on the cognitive task (semantic segmentation at hand. The higher-level segmentation results in a partition corresponding to semantic video objects. Semantic video objects do not usually have invariant physical properties and the definition depends on the application. Hence, the definition incorporates complex domain-specific knowledge and is not easy to generalize. For the specific implementation used in this paper, motion is used as a clue to semantic information. In this framework, an automatic algorithm is presented for computing the semantic partition based on color change detection. The change detection strategy is designed to be immune to the sensor noise and local illumination variations. The lower-level segmentation identifies the partition corresponding to perceptually uniform regions. These regions are derived by clustering in an -dimensional feature space, composed of static as well as dynamic image attributes. We propose an interaction mechanism between the semantic and the region partitions which allows to cope with multiple

  9. An innovative experimental sequence on electromagnetic induction and eddy currents based on video analysis and cheap data acquisition

    Science.gov (United States)

    Bonanno, A.; Bozzo, G.; Sapia, P.

    2017-11-01

    In this work, we present a coherent sequence of experiments on electromagnetic (EM) induction and eddy currents, appropriate for university undergraduate students, based on a magnet falling through a drilled aluminum disk. The sequence, leveraging on the didactical interplay between the EM and mechanical aspects of the experiments, allows us to exploit the students’ awareness of mechanics to elicit their comprehension of EM phenomena. The proposed experiments feature two kinds of measurements: (i) kinematic measurements (performed by means of high-speed video analysis) give information on the system’s kinematics and, via appropriate numerical data processing, allow us to get dynamic information, in particular on energy dissipation; (ii) induced electromagnetic field (EMF) measurements (by using a homemade multi-coil sensor connected to a cheap data acquisition system) allow us to quantitatively determine the inductive effects of the moving magnet on its neighborhood. The comparison between experimental results and the predictions from an appropriate theoretical model (of the dissipative coupling between the moving magnet and the conducting disk) offers many educational hints on relevant topics related to EM induction, such as Maxwell’s displacement current, magnetic field flux variation, and the conceptual link between induced EMF and induced currents. Moreover, the didactical activity gives students the opportunity to be trained in video analysis, data acquisition and numerical data processing.

  10. Safety Assessment of Advanced Imaging Sequences II: Simulations.

    Science.gov (United States)

    Jensen, Jørgen Arendt

    2016-01-01

    An automatic approach for simulating the emitted pressure, intensity, and mechanical index (MI) of advanced ultrasound imaging sequences is presented. It is based on a linear simulation of pressure fields using Field II, and it is hypothesized that linear simulation can attain the needed accuracy for predicting MI and I(spta.3) as required by FDA. The method is performed on four different imaging schemes and compared to measurements conducted using the SARUS experimental scanner. The sequences include focused emissions with an F-number of 2 with 64 elements that generate highly nonlinear fields. The simulation time is between 0.67 and 2.8 ms per emission and imaging point, making it possible to simulate even complex emission sequences in less than 1 s for a single spatial position. The linear simulations yield a relative accuracy on MI between -12.1% and 52.3% and for I(spta.3) between -38.6% and 62.6%, when using the impulse response of the probe estimated from an independent measurement. The accuracy is increased to between -22% and 24.5% for MI and between -33.2% and 27.0% for I(spta.3), when using the pressure response measured at a single point to scale the simulation. The spatial distribution of MI and I(ta.3) closely matches that for the measurement, and simulations can, therefore, be used to select the region for measuring the intensities, resulting in a significant reduction in measurement time. It can validate emission sequences by showing symmetry of emitted pressure fields, focal position, and intensity distribution.

  11. A Low-Complexity Algorithm for Static Background Estimation from Cluttered Image Sequences in Surveillance Contexts

    Directory of Open Access Journals (Sweden)

    Reddy Vikas

    2011-01-01

    Full Text Available Abstract For the purposes of foreground estimation, the true background model is unavailable in many practical circumstances and needs to be estimated from cluttered image sequences. We propose a sequential technique for static background estimation in such conditions, with low computational and memory requirements. Image sequences are analysed on a block-by-block basis. For each block location a representative set is maintained which contains distinct blocks obtained along its temporal line. The background estimation is carried out in a Markov Random Field framework, where the optimal labelling solution is computed using iterated conditional modes. The clique potentials are computed based on the combined frequency response of the candidate block and its neighbourhood. It is assumed that the most appropriate block results in the smoothest response, indirectly enforcing the spatial continuity of structures within a scene. Experiments on real-life surveillance videos demonstrate that the proposed method obtains considerably better background estimates (both qualitatively and quantitatively than median filtering and the recently proposed "intervals of stable intensity" method. Further experiments on the Wallflower dataset suggest that the combination of the proposed method with a foreground segmentation algorithm results in improved foreground segmentation.

  12. The research on binocular stereo video imaging and display system based on low-light CMOS

    Science.gov (United States)

    Xie, Ruobing; Li, Li; Jin, Weiqi; Guo, Hong

    2015-10-01

    It is prevalent for the low-light night-vision helmet to equip the binocular viewer with image intensifiers. Such equipment can not only acquire night vision ability, but also obtain the sense of stereo vision to achieve better perception and understanding of the visual field. However, since the image intensifier is for direct-observation, it is difficult to apply the modern image processing technology. As a result, developing digital video technology in night vision is of great significance. In this paper, we design a low-light night-vision helmet with digital imaging device. It consists of three parts: a set of two low-illumination CMOS cameras, a binocular OLED micro display and an image processing PCB. Stereopsis is achieved through the binocular OLED micro display. We choose Speed-Up Robust Feature (SURF) algorithm for image registration. Based on the image matching information and the cameras' calibration parameters, disparity can be calculated in real-time. We then elaborately derive the constraints of binocular stereo display. The sense of stereo vision can be obtained by dynamically adjusting the content of the binocular OLED micro display. There is sufficient space for function extensions in our system. The performance of this low-light night-vision helmet can be further enhanced in combination with The HDR technology and image fusion technology, etc.

  13. Silhouette extraction from human gait images sequence using cosegmentation

    Science.gov (United States)

    Chen, Jinyan; Zhang, Yi

    2012-11-01

    Gait based human identification is very useful for automatic person recognize through visual surveillance and has attracted more and more researchers. A key step in gait based human identification is to extract human silhouette from images sequence. Current silhouette extraction methods are mainly based on simple color subtraction. These methods have a very poor performance when the color of some body parts is similar to the background. In this paper a cosegmentation based human silhouette extraction method is proposed. Cosegmentation is typically defined as the task of jointly segmenting "something similar" in a given set of images. We can divide the human gait images sequence into several step cycles and every step cycle consist of 10-15 frames. The frames in human gait images sequence have following similarity: every frame is similar to the next or previous frame; every frame is similar to the corresponding frame in the next or previous step cycle; every pixel can find similar pixel in other frames. The progress of cosegmentation based human silhouette extraction can be described as follows: Initially only points which have high contrast to background are used as foreground kernel points, the points in the background are used as background kernel points, then points similar to foreground points will be added to foreground points set and the points similar to background points will be added to background points set. The definition of the similarity consider the context of the point. Experimental result shows that our method has a better performance comparing to traditional human silhouette extraction methods. Keywords: Human gait

  14. Compression and Processing of Space Image Sequences of Northern Lights and Sprites

    DEFF Research Database (Denmark)

    Forchhammer, Søren Otto; Martins, Bo; Jensen, Ole Riis

    1999-01-01

    Compression of image sequences of auroral activity as northern lights and thunderstorms with sprites is investigated.......Compression of image sequences of auroral activity as northern lights and thunderstorms with sprites is investigated....

  15. Image deblurring in video stream based on two-level image model

    Science.gov (United States)

    Mukovozov, Arseniy; Nikolaev, Dmitry; Limonova, Elena

    2017-03-01

    An iterative algorithm is proposed for blind multi-image deblurring of binary images. The binarity is the only prior restriction imposed on the image. Image formation model assumes convolution with arbitrary kernel and addition of a constant value. Penalty functional is composed using binarity constraint for regularization. The algorithm estimates the original image and distortion parameters by alternate reduction of two parts of this functional. Experimental results for natural (non-synthetic) data are present.

  16. ΤND: a thyroid nodule detection system for analysis of ultrasound images and videos.

    Science.gov (United States)

    Keramidas, Eystratios G; Maroulis, Dimitris; Iakovidis, Dimitris K

    2012-06-01

    In this paper, we present a computer-aided-diagnosis (CAD) system prototype, named TND (Thyroid Nodule Detector), for the detection of nodular tissue in ultrasound (US) thyroid images and videos acquired during thyroid US examinations. The proposed system incorporates an original methodology that involves a novel algorithm for automatic definition of the boundaries of the thyroid gland, and a novel approach for the extraction of noise resilient image features effectively representing the textural and the echogenic properties of the thyroid tissue. Through extensive experimental evaluation on real thyroid US data, its accuracy in thyroid nodule detection has been estimated to exceed 95%. These results attest to the feasibility of the clinical application of TND, for the provision of a second more objective opinion to the radiologists by exploiting image evidences.

  17. Video and thermal imaging system for monitoring interiors of high temperature reaction vessels

    Science.gov (United States)

    Saveliev, Alexei V [Chicago, IL; Zelepouga, Serguei A [Hoffman Estates, IL; Rue, David M [Chicago, IL

    2012-01-10

    A system and method for real-time monitoring of the interior of a combustor or gasifier wherein light emitted by the interior surface of a refractory wall of the combustor or gasifier is collected using an imaging fiber optic bundle having a light receiving end and a light output end. Color information in the light is captured with primary color (RGB) filters or complimentary color (GMCY) filters placed over individual pixels of color sensors disposed within a digital color camera in a BAYER mosaic layout, producing RGB signal outputs or GMCY signal outputs. The signal outputs are processed using intensity ratios of the primary color filters or the complimentary color filters, producing video images and/or thermal images of the interior of the combustor or gasifier.

  18. SU-C-18A-02: Image-Based Camera Tracking: Towards Registration of Endoscopic Video to CT

    Energy Technology Data Exchange (ETDEWEB)

    Ingram, S; Rao, A; Wendt, R; Castillo, R; Court, L [UT MD Anderson Cancer Center, Houston, TX (United States); UT Graduate School of Biomedical Sciences, Houston, TX (United States); Yang, J; Beadle, B [UT MD Anderson Cancer Center, Houston, TX (United States)

    2014-06-01

    Purpose: Endoscopic examinations are routinely performed on head and neck and esophageal cancer patients. However, these images are underutilized for radiation therapy because there is currently no way to register them to a CT of the patient. The purpose of this work is to develop a method to track the motion of an endoscope within a structure using images from standard clinical equipment. This method will be incorporated into a broader endoscopy/CT registration framework. Methods: We developed a software algorithm to track the motion of an endoscope within an arbitrary structure. We computed frame-to-frame rotation and translation of the camera by tracking surface points across the video sequence and utilizing two-camera epipolar geometry. The resulting 3D camera path was used to recover the surrounding structure via triangulation methods. We tested this algorithm on a rigid cylindrical phantom with a pattern spray-painted on the inside. We did not constrain the motion of the endoscope while recording, and we did not constrain our measurements using the known structure of the phantom. Results: Our software algorithm can successfully track the general motion of the endoscope as it moves through the phantom. However, our preliminary data do not show a high degree of accuracy in the triangulation of 3D point locations. More rigorous data will be presented at the annual meeting. Conclusion: Image-based camera tracking is a promising method for endoscopy/CT image registration, and it requires only standard clinical equipment. It is one of two major components needed to achieve endoscopy/CT registration, the second of which is tying the camera path to absolute patient geometry. In addition to this second component, future work will focus on validating our camera tracking algorithm in the presence of clinical imaging features such as patient motion, erratic camera motion, and dynamic scene illumination.

  19. Optimal context quantization in lossless compression of image data sequences

    DEFF Research Database (Denmark)

    Forchhammer, Søren; Wu, X.; Andersen, Jakob Dahl

    2004-01-01

    In image compression context-based entropy coding is commonly used. A critical issue to the performance of context-based image coding is how to resolve the conflict of a desire for large templates to model high-order statistic dependency of the pixels and the problem of context dilution due...... to insufficient sample statistics of a given input image. We consider the problem of finding the optimal quantizer Q that quantizes the K-dimensional causal context C/sub t/=(X/sub t-t1/,X/sub t-t2/,...,X/sub t-tK/) of a source symbol X/sub t/ into one of a set of conditioning states. The optimality of context...... a random variable can be decomposed into a sequence of binary decisions, each of which is coded using optimal context quantization designed for the corresponding binary random variable. This optimized coding scheme is applied to digital maps and /spl alpha-/plane sequences. The proposed optimal context...

  20. Understanding Discrete Facial Expressions in Video Using an Emotion Avatar Image.

    Science.gov (United States)

    Songfan Yang; Bhanu, B

    2012-08-01

    Existing video-based facial expression recognition techniques analyze the geometry-based and appearance-based information in every frame as well as explore the temporal relation among frames. On the contrary, we present a new image-based representation and an associated reference image called the emotion avatar image (EAI), and the avatar reference, respectively. This representation leverages the out-of-plane head rotation. It is not only robust to outliers but also provides a method to aggregate dynamic information from expressions with various lengths. The approach to facial expression analysis consists of the following steps: 1) face detection; 2) face registration of video frames with the avatar reference to form the EAI representation; 3) computation of features from EAIs using both local binary patterns and local phase quantization; and 4) the classification of the feature as one of the emotion type by using a linear support vector machine classifier. Our system is tested on the Facial Expression Recognition and Analysis Challenge (FERA2011) data, i.e., the Geneva Multimodal Emotion Portrayal-Facial Expression Recognition and Analysis Challenge (GEMEP-FERA) data set. The experimental results demonstrate that the information captured in an EAI for a facial expression is a very strong cue for emotion inference. Moreover, our method suppresses the person-specific information for emotion and performs well on unseen data.

  1. Error protection and interleaving for wireless transmission of JPEG 2000 images and video.

    Science.gov (United States)

    Baruffa, Giuseppe; Micanti, Paolo; Frescura, Fabrizio

    2009-02-01

    The transmission of JPEG 2000 images or video over wireless channels has to cope with the high probability and burstyness of errors introduced by Gaussian noise, linear distortions, and fading. At the receiver side, there is distortion due to the compression performed at the sender side, and to the errors introduced in the data stream by the channel. Progressive source coding can also be successfully exploited to protect different portions of the data stream with different channel code rates, based upon the relative importance that each portion has on the reconstructed image. Unequal Error Protection (UEP) schemes are generally adopted, which offer a close to the optimal solution. In this paper, we present a dichotomic technique for searching the optimal UEP strategy, which lends ideas from existing algorithms, for the transmission of JPEG 2000 images and video over a wireless channel. Moreover, we also adopt a method of virtual interleaving to be used for the transmission of high bit rate streams over packet loss channels, guaranteeing a large PSNR advantage over a plain transmission scheme. These two protection strategies can also be combined to maximize the error correction capabilities.

  2. Image ranking in video sequences using pairwise image comparisons and temporal smoothing

    CSIR Research Space (South Africa)

    Burke, Michael

    2016-12-01

    Full Text Available ’ values within a standard Bayesian ranking framework, and a Rauch-Tung-Striebel smoother is used to improve these interest scores. Results show that the training data requirements typically associated with pairwise ranking systems are dramatically reduced...

  3. Deep linear autoencoder and patch clustering-based unified one-dimensional coding of image and video

    Science.gov (United States)

    Li, Honggui

    2017-09-01

    This paper proposes a unified one-dimensional (1-D) coding framework of image and video, which depends on deep learning neural network and image patch clustering. First, an improved K-means clustering algorithm for image patches is employed to obtain the compact inputs of deep artificial neural network. Second, for the purpose of best reconstructing original image patches, deep linear autoencoder (DLA), a linear version of the classical deep nonlinear autoencoder, is introduced to achieve the 1-D representation of image blocks. Under the circumstances of 1-D representation, DLA is capable of attaining zero reconstruction error, which is impossible for the classical nonlinear dimensionality reduction methods. Third, a unified 1-D coding infrastructure for image, intraframe, interframe, multiview video, three-dimensional (3-D) video, and multiview 3-D video is built by incorporating different categories of videos into the inputs of patch clustering algorithm. Finally, it is shown in the results of simulation experiments that the proposed methods can simultaneously gain higher compression ratio and peak signal-to-noise ratio than those of the state-of-the-art methods in the situation of low bitrate transmission.

  4. Individual differences in the processing of smoking-cessation video messages: An imaging genetics study.

    Science.gov (United States)

    Shi, Zhenhao; Wang, An-Li; Aronowitz, Catherine A; Romer, Daniel; Langleben, Daniel D

    2017-09-01

    Studies testing the benefits of enriching smoking-cessation video ads with attention-grabbing sensory features have yielded variable results. Dopamine transporter gene (DAT1) has been implicated in attention deficits. We hypothesized that DAT1 polymorphism is partially responsible for this variability. Using functional magnetic resonance imaging, we examined brain responses to videos high or low in attention-grabbing features, indexed by "message sensation value" (MSV), in 53 smokers genotyped for DAT1. Compared to other smokers, 10/10 homozygotes showed greater neural response to High- vs. Low-MSV smoking-cessation videos in two a priori regions of interest: the right temporoparietal junction and the right ventrolateral prefrontal cortex. These regions are known to underlie stimulus-driven attentional processing. Exploratory analysis showed that the right temporoparietal response positively predicted follow-up smoking behavior indexed by urine cotinine. Our findings suggest that responses to attention-grabbing features in smoking-cessation messages is affected by the DAT1 genotype. Copyright © 2017. Published by Elsevier B.V.

  5. Simulation of video sequences for an accurate evaluation of tracking algorithms on complex scenes

    Science.gov (United States)

    Dubreu, Christine; Manzanera, Antoine; Bohain, Eric

    2008-04-01

    As target tracking is arousing more and more interest, the necessity to reliably assess tracking algorithms in any conditions is becoming essential. The evaluation of such algorithms requires a database of sequences representative of the whole range of conditions in which the tracking system is likely to operate, together with its associated ground truth. However, building such a database with real sequences, and collecting the associated ground truth appears to be hardly possible and very time-consuming. Therefore, more and more often, synthetic sequences are generated by complex and heavy simulation platforms to evaluate the performance of tracking algorithms. Some methods have also been proposed using simple synthetic sequences generated without such complex simulation platforms. These sequences are generated from a finite number of discriminating parameters, and are statistically representative, as regards these parameters, of real sequences. They are very simple and not photorealistic, but can be reliably used for low-level tracking algorithms evaluation in any operating conditions. The aim of this paper is to assess the reliability of these non-photorealistic synthetic sequences for evaluation of tracking systems on complex-textured objects, and to show how the number of parameters can be increased to synthesize more elaborated scenes and deal with more complex dynamics, including occlusions and three-dimensional deformations.

  6. In situ calibration of an infrared imaging video bolometer in the Large Helical Device

    Energy Technology Data Exchange (ETDEWEB)

    Mukai, K., E-mail: mukai.kiyofumi@LHD.nifs.ac.jp; Peterson, B. J. [National Institute for Fusion Science, 322-6 Oroshi-cho, Toki 509-5292 (Japan); Pandya, S. N.; Sano, R. [The Graduate University for Advance Studies, 322-6 Oroshi-cho, Toki 509-5292 (Japan)

    2014-11-15

    The InfraRed imaging Video Bolometer (IRVB) is a powerful diagnostic to measure multi-dimensional radiation profiles in plasma fusion devices. In the Large Helical Device (LHD), four IRVBs have been installed with different fields of view to reconstruct three-dimensional profiles using a tomography technique. For the application of the measurement to plasma experiments using deuterium gas in LHD in the near future, the long-term effect of the neutron irradiation on the heat characteristics of an IRVB foil should be taken into account by regular in situ calibration measurements. Therefore, in this study, an in situ calibration system was designed.

  7. Positive effect on patient experience of video information given prior to cardiovascular magnetic resonance imaging: A clinical trial.

    Science.gov (United States)

    Ahlander, Britt-Marie; Engvall, Jan; Maret, Eva; Ericsson, Elisabeth

    2017-11-17

    To evaluate the effect of video information given before cardiovascular magnetic resonance imaging on patient anxiety and to compare patient experiences of cardiovascular magnetic resonance imaging versus myocardial perfusion scintigraphy. To evaluate whether additional information has an impact on motion artefacts. Cardiovascular magnetic resonance imaging and myocardial perfusion scintigraphy are technically advanced methods for the evaluation of heart diseases. Although cardiovascular magnetic resonance imaging is considered to be painless, patients may experience anxiety due to the closed environment. A prospective randomised intervention study, not registered. The sample (n = 148) consisted of 97 patients referred for cardiovascular magnetic resonance imaging, randomised to receive either video information in addition to standard text-information (CMR-video/n = 49) or standard text-information alone (CMR-standard/n = 48). A third group undergoing myocardial perfusion scintigraphy (n = 51) was compared with the cardiovascular magnetic resonance imaging-standard group. Anxiety was evaluated before, immediately after the procedure and 1 week later. Five questionnaires were used: Cardiac Anxiety Questionnaire, State-Trait Anxiety Inventory, Hospital Anxiety and Depression scale, MRI Fear Survey Schedule and the MRI-Anxiety Questionnaire. Motion artefacts were evaluated by three observers, blinded to the information given. Data were collected between April 2015-April 2016. The study followed the CONSORT guidelines. The CMR-video group scored lower (better) than the cardiovascular magnetic resonance imaging-standard group in the factor Relaxation (p = .039) but not in the factor Anxiety. Anxiety levels were lower during scintigraphic examinations compared to the CMR-standard group (p magnetic resonance imaging increased by adding video information prior the exam, which is important in relation to perceived quality in nursing. No effect was seen on motion

  8. Lossless Compression of Broadcast Video

    DEFF Research Database (Denmark)

    Martins, Bo; Eriksen, N.; Faber, E.

    1998-01-01

    We investigate several techniques for lossless and near-lossless compression of broadcast video.The emphasis is placed on the emerging international standard for compression of continous-tone still images, JPEG-LS, due to its excellent compression performance and moderatecomplexity. Except for one...... artificial sequence containing uncompressible data all the 4:2:2, 8-bit test video material easily compresses losslessly to a rate below 125 Mbit/s. At this rate, video plus overhead can be contained in a single telecom 4th order PDH channel or a single STM-1 channel. Difficult 4:2:2, 10-bit test material...

  9. Development and preliminary evaluation of an online educational video about whole-genome sequencing for research participants, patients, and the general public.

    Science.gov (United States)

    Sanderson, Saskia C; Suckiel, Sabrina A; Zweig, Micol; Bottinger, Erwin P; Jabs, Ethylin Wang; Richardson, Lynne D

    2016-05-01

    As whole-genome sequencing (WGS) increases in availability, WGS educational aids are needed for research participants, patients, and the general public. Our aim was therefore to develop an accessible and scalable WGS educational aid. We engaged multiple stakeholders in an iterative process over a 1-year period culminating in the production of a novel 10-minute WGS educational animated video, "Whole Genome Sequencing and You" (https://goo.gl/HV8ezJ). We then presented the animated video to 281 online-survey respondents (the video-information group). There were also two comparison groups: a written-information group (n = 281) and a no-information group (n = 300). In the video-information group, 79% reported the video was easy to understand, satisfaction scores were high (mean 4.00 on 1-5 scale, where 5 = high satisfaction), and knowledge increased significantly. There were significant differences in knowledge compared with the no-information group but few differences compared with the written-information group. Intention to receive personal results from WGS and decisional conflict in response to a hypothetical scenario did not differ between the three groups. The educational animated video, "Whole Genome Sequencing and You," was well received by this sample of online-survey respondents. Further work is needed to evaluate its utility as an aid to informed decision making about WGS in other populations.Genet Med 18 5, 501-512.

  10. Dynamical Segmentation of the Left Ventricle in Echocardiographic Image Sequences

    Science.gov (United States)

    2001-10-25

    1 DYNAMICAL SEGMENTATION OF THE LEFT VENTRICLE IN ECHOCARDIOGRAPHIC IMAGE SEQUENCES A. Bosnjak1,2, V. Burdin 1, V. Torrealba 2, G. Montilla 2, B...V, Bosnjak A, Acuña M, Hernández L, Roux C, Montilla G. “3D Dynamics Echocardiography. Workstation for the Acquisition, Reconstruction and...Torrealba V., Hernández L., Acuña M., Montilla G., Bosnjak A., Roux C. “Interpolación Espacial de Imágenes Médicas 3D basada en movimiento”. Avances

  11. LUM Smoother with Smooth Control for Noisy Image Sequences

    Directory of Open Access Journals (Sweden)

    Lukàč Rastislav

    2001-01-01

    Full Text Available This paper focuses on adaptive structure of LUM (lower-upper-middle smoothers for noisy image sequences. For the balance between noise suppression and signal-detail preservation, the LUM smoothers are widely used in smoothing applications. The amount of smoothing done by LUM smoothers is controlled by tuning parameter. However, the smoothing level is fixed for whole image. Thus, the excessive or insufficient smoothing can be performed. This problem is solved by a new method based on the adaptive controlled level of smoothing. A new method has excellent performance of the noise reduction in the environments corrupted by the impulse noise. In addition, minimal signal-detail and motion blurring can be observed. The performance of proposed method is evaluated through objective criteria and compared with traditional temporal, spatial, and spatiotemporal LUM smoothers.

  12. Influence of image compression on the quality of UNB pan-sharpened imagery: a case study with security video image frames

    Science.gov (United States)

    Adhamkhiabani, Sina Adham; Zhang, Yun; Fathollahi, Fatemeh

    2014-05-01

    UNB Pan-sharp, also named FuzeGo, is an image fusion technique to produce high resolution color satellite images by fusing a high resolution panchromatic (monochrome) image and a low resolution multispectral (color) image. This is an effective solution that modern satellites have been using to capture high resolution color images at an ultra-high speed. Initial research on security camera systems shows that the UNB Pan-sharp technique can also be utilized to produce high resolution and high sensitive color video images for various imaging and monitoring applications. Based on UNB Pansharp technique, a video camera prototype system, called the UNB Super-camera system, was developed that captures high resolution panchromatic images and low resolution color images simultaneously, and produces real-time high resolution color video images on the fly. In a separate study, it was proved that UNB Super Camera outperforms conventional 1-chip and 3-chip color cameras in image quality, especially when the illumination is low such as in room lighting. In this research the influence of image compression on the quality of UNB Pan-sharped high resolution color images is evaluated, since image compression is widely used in still and video cameras to reduce data volume and speed up data transfer. The results demonstrate that UNB Pan-sharp can consistently produce high resolution color images that have the same detail as the input high resolution panchromatic image and the same color of the input low resolution color image, regardless the compression ratio and lighting condition. In addition, the high resolution color images produced by UNB Pan-sharp have higher sensitivity (signal to noise ratio) and better edge sharpness and color rendering than those of the same generation 1-chip color camera, regardless the compression ratio and lighting condition.

  13. Automated method for tracing leading and trailing processes of migrating neurons in confocal image sequences

    Science.gov (United States)

    Kerekes, Ryan A.; Gleason, Shaun S.; Trivedi, Niraj; Solecki, David J.

    2010-03-01

    Segmentation, tracking, and tracing of neurons in video imagery are important steps in many neuronal migration studies and can be inaccurate and time-consuming when performed manually. In this paper, we present an automated method for tracing the leading and trailing processes of migrating neurons in time-lapse image stacks acquired with a confocal fluorescence microscope. In our approach, we first locate and track the soma of the cell of interest by smoothing each frame and tracking the local maxima through the sequence. We then trace the leading process in each frame by starting at the center of the soma and stepping repeatedly in the most likely direction of the leading process. This direction is found at each step by examining second derivatives of fluorescent intensity along curves of constant radius around the current point. Tracing terminates after a fixed number of steps or when fluorescent intensity drops below a fixed threshold. We evolve the resulting trace to form an improved trace that more closely follows the approximate centerline of the leading process. We apply a similar algorithm to the trailing process of the cell by starting the trace in the opposite direction. We demonstrate our algorithm on two time-lapse confocal video sequences of migrating cerebellar granule neurons (CGNs). We show that the automated traces closely approximate ground truth traces to within 1 or 2 pixels on average. Additionally, we compute line intensity profiles of fluorescence along the automated traces and quantitatively demonstrate their similarity to manually generated profiles in terms of fluorescence peak locations.

  14. Security SVGA image sensor with on-chip video data authentication and cryptographic circuit

    Science.gov (United States)

    Stifter, P.; Eberhardt, K.; Erni, A.; Hofmann, K.

    2005-10-01

    Security applications of sensors in a networking environment has a strong demand of sensor authentication and secure data transmission due to the possibility of man-in-the-middle and address spoofing attacks. Therefore a secure sensor system should fulfil the three standard requirements of cryptography, namely data integrity, authentication and non-repudiation. This paper is intended to present the unique sensor development by AIM, the so called SecVGA, which is a high performance, monochrome (B/W) CMOS active pixel image sensor. The device is capable of capturing still and motion images with a resolution of 800x600 active pixels and converting the image into a digital data stream. The distinguishing feature of this development in comparison to standard imaging sensors is the on-chip cryptographic engine which provides the sensor authentication, based on a one-way challenge/response protocol. The implemented protocol results in the exchange of a session-key which will secure the following video data transmission. This is achieved by calculating a cryptographic checksum derived from a stateful hash value of the complete image frame. Every sensor contains an EEPROM memory cell for the non-volatile storage of a unique identifier. The imager is programmable via a two-wire I2C compatible interface which controls the integration time, the active window size of the pixel array, the frame rate and various operating modes including the authentication procedure.

  15. A phase field method for joint denoising, edge detection, and motion estimation in image sequence processing

    NARCIS (Netherlands)

    Preusser, T.; Droske, M.; Garbe, C. S.; Telea, A.; Rumpf, M.

    2007-01-01

    The estimation of optical flow fields from image sequences is incorporated in a Mumford-Shah approach for image denoising and edge detection. Possibly noisy image sequences are considered as input and a piecewise smooth image intensity, a piecewise smooth motion field, and a joint discontinuity set

  16. [Images of Alu-sequence in 7 DNA clones from the human genome].

    Science.gov (United States)

    Korotkov, E V

    1987-01-01

    Information theory methods were used for computer search of Alu-like sequences in human DNA and RNA. Eight new regions related to the Alu repeat sequence was revealed in 85 clones from the EMBL-5 data bank. Some of these regions are purine-pyrimidine images of Alu repeats sequence, the rest are more complex images of Alu repeat sequence. A new definition for the likeness of different sequences--information image of sequence--was introduced. This information theory application greatly increases the power of DNA sequences computer analysis.

  17. Real-Time Human Detection for Aerial Captured Video Sequences via Deep Models

    Directory of Open Access Journals (Sweden)

    Nouar AlDahoul

    2018-01-01

    Full Text Available Human detection in videos plays an important role in various real life applications. Most of traditional approaches depend on utilizing handcrafted features which are problem-dependent and optimal for specific tasks. Moreover, they are highly susceptible to dynamical events such as illumination changes, camera jitter, and variations in object sizes. On the other hand, the proposed feature learning approaches are cheaper and easier because highly abstract and discriminative features can be produced automatically without the need of expert knowledge. In this paper, we utilize automatic feature learning methods which combine optical flow and three different deep models (i.e., supervised convolutional neural network (S-CNN, pretrained CNN feature extractor, and hierarchical extreme learning machine for human detection in videos captured using a nonstatic camera on an aerial platform with varying altitudes. The models are trained and tested on the publicly available and highly challenging UCF-ARG aerial dataset. The comparison between these models in terms of training, testing accuracy, and learning speed is analyzed. The performance evaluation considers five human actions (digging, waving, throwing, walking, and running. Experimental results demonstrated that the proposed methods are successful for human detection task. Pretrained CNN produces an average accuracy of 98.09%. S-CNN produces an average accuracy of 95.6% with soft-max and 91.7% with Support Vector Machines (SVM. H-ELM has an average accuracy of 95.9%. Using a normal Central Processing Unit (CPU, H-ELM’s training time takes 445 seconds. Learning in S-CNN takes 770 seconds with a high performance Graphical Processing Unit (GPU.

  18. RST-Resilient Video Watermarking Using Scene-Based Feature Extraction

    OpenAIRE

    Jung Han-Seung; Lee Young-Yoon; Lee Sang Uk

    2004-01-01

    Watermarking for video sequences should consider additional attacks, such as frame averaging, frame-rate change, frame shuffling or collusion attacks, as well as those of still images. Also, since video is a sequence of analogous images, video watermarking is subject to interframe collusion. In order to cope with these attacks, we propose a scene-based temporal watermarking algorithm. In each scene, segmented by scene-change detection schemes, a watermark is embedded temporally to one-dimens...

  19. High-quality and small-capacity e-learning video featuring lecturer-superimposing PC screen images

    Science.gov (United States)

    Nomura, Yoshihiko; Murakami, Michinobu; Sakamoto, Ryota; Sugiura, Tokuhiro; Matsui, Hirokazu; Kato, Norihiko

    2006-10-01

    Information processing and communication technology are progressing quickly, and are prevailing throughout various technological fields. Therefore, the development of such technology should respond to the needs for improvement of quality in the e-learning education system. The authors propose a new video-image compression processing system that ingeniously employs the features of the lecturing scene. While dynamic lecturing scene is shot by a digital video camera, screen images are electronically stored by a PC screen image capturing software in relatively long period at a practical class. Then, a lecturer and a lecture stick are extracted from the digital video images by pattern recognition techniques, and the extracted images are superimposed on the appropriate PC screen images by off-line processing. Thus, we have succeeded to create a high-quality and small-capacity (HQ/SC) video-on-demand educational content featuring the advantages: the high quality of image sharpness, the small electronic file capacity, and the realistic lecturer motion.

  20. Facial Expression Recognition from Video Sequences Based on Spatial-Temporal Motion Local Binary Pattern and Gabor Multiorientation Fusion Histogram

    Directory of Open Access Journals (Sweden)

    Lei Zhao

    2017-01-01

    Full Text Available This paper proposes novel framework for facial expressions analysis using dynamic and static information in video sequences. First, based on incremental formulation, discriminative deformable face alignment method is adapted to locate facial points to correct in-plane head rotation and break up facial region from background. Then, spatial-temporal motion local binary pattern (LBP feature is extracted and integrated with Gabor multiorientation fusion histogram to give descriptors, which reflect static and dynamic texture information of facial expressions. Finally, a one-versus-one strategy based multiclass support vector machine (SVM classifier is applied to classify facial expressions. Experiments on Cohn-Kanade (CK + facial expression dataset illustrate that integrated framework outperforms methods using single descriptors. Compared with other state-of-the-art methods on CK+, MMI, and Oulu-CASIA VIS datasets, our proposed framework performs better.

  1. Direct ultrasound to video registration using photoacoustic markers from a single image pose

    Science.gov (United States)

    Cheng, Alexis; Guo, Xiaoyu; Kang, Hyun Jae; Choti, Michael A.; Kang, Jin U.; Taylor, Russell H.; Boctor, Emad M.

    2015-03-01

    Fusion of video and other imaging modalities is common in modern surgical scenarios to provide surgeons with additional information. Doing so requires the use of interventional guidance equipment and surgical navigation systems to register the tools and devices used in surgery with each other. In this work, we focus explicitly on registering ultrasound with a stereocamera system using photoacoustic markers. Previous work has shown that photoacoustic markers can be used to register three-dimensional ultrasound with video resulting in target registration errors lower than the current available systems. Photoacoustic markers are non-collinear laser spots projected onto some surface. They can be simultaneously visualized by a stereocamera system and in an ultra-sound volume because of the photoacoustic effect. This work replaces the three-dimensional ultrasound volume with images from a single ultrasound image pose. While an ultrasound volume provides more information than an ultrasound image, it has its disadvantages such as higher cost and slower acquisition rate. However, in general, it is difficult to register two-dimensional with three-dimensional spatial data. We propose the use of photoacoustic markers viewed by a convex array ultrasound transducer. Each photoacoustic markers wavefront provides information on its elevational position, resulting in three-dimensional spatial data. This development enhances this methods practicality as convex array transducers are more common in surgical practice than three-dimensional transducers. This work is demonstrated on a synthetic phantom. The resulting target registration error for this experiment was 2.47mm and the standard deviations was 1.29mm, which is comparable to current available systems.

  2. Realization of a video-rate distributed aperture millimeter-wave imaging system using optical upconversion

    Science.gov (United States)

    Schuetz, Christopher; Martin, Richard; Dillon, Thomas; Yao, Peng; Mackrides, Daniel; Harrity, Charles; Zablocki, Alicia; Shreve, Kevin; Bonnett, James; Curt, Petersen; Prather, Dennis

    2013-05-01

    Passive imaging using millimeter waves (mmWs) has many advantages and applications in the defense and security markets. All terrestrial bodies emit mmW radiation and these wavelengths are able to penetrate smoke, fog/clouds/marine layers, and even clothing. One primary obstacle to imaging in this spectrum is that longer wavelengths require larger apertures to achieve the resolutions desired for many applications. Accordingly, lens-based focal plane systems and scanning systems tend to require large aperture optics, which increase the achievable size and weight of such systems to beyond what can be supported by many applications. To overcome this limitation, a distributed aperture detection scheme is used in which the effective aperture size can be increased without the associated volumetric increase in imager size. This distributed aperture system is realized through conversion of the received mmW energy into sidebands on an optical carrier. This conversion serves, in essence, to scale the mmW sparse aperture array signals onto a complementary optical array. The side bands are subsequently stripped from the optical carrier and recombined to provide a real time snapshot of the mmW signal. Using this technique, we have constructed a real-time, video-rate imager operating at 75 GHz. A distributed aperture consisting of 220 upconversion channels is used to realize 2.5k pixels with passive sensitivity. Details of the construction and operation of this imager as well as field testing results will be presented herein.

  3. Deformation analysis of the vocal folds from videostroboscopic image sequences of the larynx.

    Science.gov (United States)

    Saadah, A K; Galatsanos, N P; Bless, D; Ramos, C A

    1998-06-01

    Videostroboscopy is an examination which yields a permanent record of the moving vocal folds. Thus, it allows the diagnosis of abnormalities which contribute to voice disorders. In this paper, in order to find and quantify the deformation of the vocal folds in videostroboscopic recordings, an active contours- (snakes) based approach is used to delineate the vocal folds in each frame of the videostroboscopic image sequence. After this delineation, a new elastic registration algorithm is used to register the vocal fold contours between adjacent frames of the video sequence. This algorithm is based on the regularization principle and is very effective when large deformations are present. A least-squares approach is used to fit an affine model to the displacement vectors found by elastic registration. The parameters of this model, rotation, translation, and deformation along two principle axes, quantify the deformation and allow the succinct characterization of the videostroboscopic recordings based on the deformations that occurred. Experiments are shown with synthetic and real videostroboscopic data that demonstrate the value of the proposed approach.

  4. Detection of distorted frames in retinal video-sequences via machine learning

    Science.gov (United States)

    Kolar, Radim; Liberdova, Ivana; Odstrcilik, Jan; Hracho, Michal; Tornow, Ralf P.

    2017-07-01

    This paper describes detection of distorted frames in retinal sequences based on set of global features extracted from each frame. The feature vector is consequently used in classification step, in which three types of classifiers are tested. The best classification accuracy 96% has been achieved with support vector machine approach.

  5. Probabilistic multi-person localisation and tracking in image sequences

    Science.gov (United States)

    Klinger, T.; Rottensteiner, F.; Heipke, C.

    2017-05-01

    The localisation and tracking of persons in image sequences in commonly guided by recursive filters. Especially in a multi-object tracking environment, where mutual occlusions are inherent, the predictive model is prone to drift away from the actual target position when not taking context into account. Further, if the image-based observations are imprecise, the trajectory is prone to be updated towards a wrong position. In this work we address both these problems by using a new predictive model on the basis of Gaussian Process Regression, and by using generic object detection, as well as instance-specific classification, for refined localisation. The predictive model takes into account the motion of every tracked pedestrian in the scene and the prediction is executed with respect to the velocities of neighbouring persons. In contrast to existing methods our approach uses a Dynamic Bayesian Network in which the state vector of a recursive Bayes filter, as well as the location of the tracked object in the image, are modelled as unknowns. This allows the detection to be corrected before it is incorporated into the recursive filter. Our method is evaluated on a publicly available benchmark dataset and outperforms related methods in terms of geometric precision and tracking accuracy.

  6. Real-Time Recognition of Action Sequences Using a DistributedVideo Sensor Network

    Directory of Open Access Journals (Sweden)

    Vinod Kulathumani

    2013-07-01

    Full Text Available In this paper, we describe how information obtained from multiple views usinga network of cameras can be effectively combined to yield a reliable and fast humanactivity recognition system. First, we present a score-based fusion technique for combininginformation from multiple cameras that can handle the arbitrary orientation of the subjectwith respect to the cameras and that does not rely on a symmetric deployment of thecameras. Second, we describe how longer, variable duration, inter-leaved action sequencescan be recognized in real-time based on multi-camera data that is continuously streaming in.Our framework does not depend on any particular feature extraction technique, and as aresult, the proposed system can easily be integrated on top of existing implementationsfor view-specific classifiers and feature descriptors. For implementation and testing of theproposed system, we have used computationally simple locality-specific motion informationextracted from the spatio-temporal shape of a human silhouette as our feature descriptor.This lends itself to an efficient distributed implementation, while maintaining a high framecapture rate. We demonstrate the robustness of our algorithms by implementing them ona portable multi-camera, video sensor network testbed and evaluating system performanceunder different camera network configurations.

  7. Video-rate bioluminescence imaging of matrix metalloproteinase-2 secreted from a migrating cell.

    Directory of Open Access Journals (Sweden)

    Takahiro Suzuki

    Full Text Available BACKGROUND: Matrix metalloproteinase-2 (MMP-2 plays an important role in cancer progression and metastasis. MMP-2 is secreted as a pro-enzyme, which is activated by the membrane-bound proteins, and the polarized distribution of secretory and the membrane-associated MMP-2 has been investigated. However, the real-time visualizations of both MMP-2 secretion from the front edge of a migration cell and its distribution on the cell surface have not been reported. METHODOLOGY/PRINCIPAL FINDINGS: The method of video-rate bioluminescence imaging was applied to visualize exocytosis of MMP-2 from a living cell using Gaussia luciferase (GLase as a reporter. The luminescence signals of GLase were detected by a high speed electron-multiplying charge-coupled device camera (EM-CCD camera with a time resolution within 500 ms per image. The fusion protein of MMP-2 to GLase was expressed in a HeLa cell and exocytosis of MMP-2 was detected in a few seconds along the leading edge of a migrating HeLa cell. The membrane-associated MMP-2 was observed at the specific sites on the bottom side of the cells, suggesting that the sites of MMP-2 secretion are different from that of MMP-2 binding. CONCLUSIONS: We were the first to successfully demonstrate secretory dynamics of MMP-2 and the specific sites for polarized distribution of MMP-2 on the cell surface. The video-rate bioluminescence imaging using GLase is a useful method to investigate distribution and dynamics of secreted proteins on the whole surface of polarized cells in real time.

  8. Cryptanalysis of a spatiotemporal chaotic image/video cryptosystem and its improved version

    Energy Technology Data Exchange (ETDEWEB)

    Ge Xin, E-mail: gexiner@gmail.co [Zhengzhou Information Science and Technology Institute, Zhengzhou 450002, Henan (China); Liu Fenlin; Lu Bin; Wang Wei [Zhengzhou Information Science and Technology Institute, Zhengzhou 450002, Henan (China)

    2011-01-31

    Recently, a spatiotemporal chaotic image/video cryptosystem was proposed by Lian. Shortly after its publication, Rhouma et al. proposed two attacks on the cryptosystem. They as well introduced an improved cryptosystem which is more secured under attacks (R. Rhouma, S. Belghith, Phys. Lett. A 372 (2008) 5790) . This Letter re-examines securities of Lian's cryptosystem and its improved version, by showing that not all details of the ciphered image of Lian's cryptosystem can be recovered by Rhouma et al.'s attacks due to the incorrectly recovered part of the sign-bits of the AC coefficients with an inappropriately chosen image. As a result, modifications of Rhouma et al.'s attacks are proposed in order to recover the ciphered image of Lian's cryptosystem completely; then based on the modifications, two new attacks are proposed to break the improved version of Lian's cryptosystem. Finally, experimental results illustrate the validity of our analysis.

  9. Approximate Circuits in Low-Power Image and Video Processing: The Approximate Median Filter

    Directory of Open Access Journals (Sweden)

    L. Sekanina

    2017-09-01

    Full Text Available Low power image and video processing circuits are crucial in many applications of computer vision. Traditional techniques used to reduce power consumption in these applications have recently been accompanied by circuit approximation methods which exploit the fact that these applications are highly error resilient and, hence, the quality of image processing can be traded for power consumption. On the basis of a literature survey, we identified the components whose implementations are the most frequently approximated and the methods used for obtaining these approximations. One of the components is the median image filter. We propose, evaluate and compare two approximation strategies based on Cartesian genetic programming applied to approximate various common implementations of the median filter. For filters developed using these approximation strategies, trade-offs between the quality of filtering and power consumption are investigated. Under conditions of our experiments we conclude that better trade-offs are achieved when the image filter is evolved from scratch rather than a conventional filter is approximated.

  10. Higher-order singular value decomposition-based discrete fractional random transform for simultaneous compression and encryption of video images

    Science.gov (United States)

    Wang, Qingzhu; Chen, Xiaoming; Zhu, Yihai

    2017-09-01

    Existing image compression and encryption methods have several shortcomings: they have low reconstruction accuracy and are unsuitable for three-dimensional (3D) images. To overcome these limitations, this paper proposes a tensor-based approach adopting tensor compressive sensing and tensor discrete fractional random transform (TDFRT). The source video images are measured by three key-controlled sensing matrices. Subsequently, the resulting tensor image is further encrypted using 3D cat map and the proposed TDFRT, which is based on higher-order singular value decomposition. A multiway projection algorithm is designed to reconstruct the video images. The proposed algorithm can greatly reduce the data volume and improve the efficiency of the data transmission and key distribution. The simulation results validate the good compression performance, efficiency, and security of the proposed algorithm.

  11. Comparison Of Processing Time Of Different Size Of Images And Video Resolutions For Object Detection Using Fuzzy Inference System

    Directory of Open Access Journals (Sweden)

    Yogesh Yadav

    2017-01-01

    Full Text Available Object Detection with small computation cost and processing time is a necessity in diverse domains such as traffic analysis security cameras video surveillance etc .With current advances in technology and decrease in prices of image sensors and video cameras the resolution of captured images is more than 1MP and has higher frame rates. This implies a considerable data size that needs to be processed in a very short period of time when real-time operations and data processing is needed. Real time video processing with high performance can be achieved with GPU technology. The aim of this study is to evaluate the influence of different image and video resolutions on the processing time number of objects detections and accuracy of the detected object. MOG2 algorithm is used for processing video input data with GPU module. Fuzzy interference system is used to evaluate the accuracy of number of detected object and to show the difference between CPU and GPU computing methods.

  12. Video-mosaicking of in vivo reflectance confocal microscopy images for noninvasive examination of skin lesion (Conference Presentation)

    Science.gov (United States)

    Kose, Kivanc; Gou, Mengran; Yelamos, Oriol; Cordova, Miguel A.; Rossi, Anthony; Nehal, Kishwer S.; Camps, Octavia I.; Dy, Jennifer G.; Brooks, Dana H.; Rajadhyaksha, Milind

    2017-02-01

    In this report we describe a computer vision based pipeline to convert in-vivo reflectance confocal microscopy (RCM) videos collected with a handheld system into large field of view (FOV) mosaics. For many applications such as imaging of hard to access lesions, intraoperative assessment of MOHS margins, or delineation of lesion margins beyond clinical borders, raster scan based mosaicing techniques have clinically significant limitations. In such cases, clinicians often capture RCM videos by freely moving a handheld microscope over the area of interest, but the resulting videos lose large-scale spatial relationships. Videomosaicking is a standard computational imaging technique to register, and stitch together consecutive frames of videos into large FOV high resolution mosaics. However, mosaicing RCM videos collected in-vivo has unique challenges: (i) tissue may deform or warp due to physical contact with the microscope objective lens, (ii) discontinuities or "jumps" between consecutive images and motion blur artifacts may occur, due to manual operation of the microscope, and (iii) optical sectioning and resolution may vary between consecutive images due to scattering and aberrations induced by changes in imaging depth and tissue morphology. We addressed these challenges by adapting or developing new algorithmic methods for videomosaicking, specifically by modeling non-rigid deformations, followed by automatically detecting discontinuities (cut locations) and, finally, applying a data-driven image stitching approach that fully preserves resolution and tissue morphologic detail without imposing arbitrary pre-defined boundaries. We will present example mosaics obtained by clinical imaging of both melanoma and non-melanoma skin cancers. The ability to combine freehand mosaicing for handheld microscopes with preserved cellular resolution will have high impact application in diverse clinical settings, including low-resource healthcare systems.

  13. Symbolic representation and visual querying of left ventricular image sequences.

    Science.gov (United States)

    Baroni, M; Del Bimbo, A; Evangelist, A; Vicario, E

    1999-01-01

    In the evaluation of regional left ventricular function, relevant cardiac disorders manifest themselves not only in static features, such as shape descriptors and motion excursion in end-diastolic and end-systolic frames, but also in their temporal evolution. In common diagnostic practice, such dynamic patterns are analysed by direct inspection of frame sequences through the use of a moviola. This permits only a subjective and poorly defined evaluation of functional parameters, and definitely prevents a systematic and reproducible analysis of large sets of reports. Retrieval by contents techniques may overcome this limitation by permitting the automatic comparison of the reports in a database against queries expressing descriptive properties related to significant pathological conditions. A system is presented which is aimed at investigating the potential of this approach by supporting retrieval by contents from a database of cineangiographic or echocardiographic images. The system relies on a symbolic description of both geometrical and temporal properties of left ventricular contours. This is derived automatically by an image processing and interpretation module and associated with the report at its storage time. In the retrieval stage, queries are expressed by means of an iconic visual language which describes searched content properties over a computer screen. The system automatically interprets iconic statements and compares them against concrete descriptions in the database. This enables medical users to interact with the system to search for motion and shape abnormalities on a regional basis, in single or homogeneous groups of reports, so as to enable both prospective and retrospective diagnosis.

  14. Submillimeter Imaging of Dust Around Main Sequence Stars

    Science.gov (United States)

    Jewitt, David

    1998-01-01

    This grant was to image circumstellar dust disks surrounding main-sequence stars. The delivery of the SCUBA detector we had planned to use for this work was delayed repeatedly, leading us to undertake a majority of the observations with the UKT14 submillimeter detector at the JCMT (James Clerk Maxwell Telescope) and optical imagers and a coronagraph at the University of Hawaii 2.2-m telescope. Major findings under this grant include: (1) We discovered 5 asymmetries in the beta Pictoris regenerated dust disk. The discovery of these asymmetries was a surprise, since smearing due to Keplerian shear should eliminate most such features on timescales of a few thousand years. One exception is the "wing tilt" asymmetry, which we interpret as due to the scattering phase function of dust disk particles. From the wing tilt and a model of the phase function, we find a disk plane inclination to the line of sight of JCMT). It is possible, for instance, that the main 850 micro-m blob is merely a galaxy or other high-z source projected onto the beta Pic mid-plane.

  15. Image and video based remote target localization and tracking on smartphones

    Science.gov (United States)

    Wang, Qia; Lobzhanidze, Alex; Jang, Hyun; Zeng, Wenjun; Shang, Yi; Yang, Jingyu

    2012-06-01

    Smartphones are becoming popular nowadays not only because of its communication functionality but also, more importantly, its powerful sensing and computing capability. In this paper, we describe a novel and accurate image and video based remote target localization and tracking system using the Android smartphones, by leveraging its built-in sensors such as camera, digital compass, GPS, etc. Even though many other distance estimation or localization devices are available, our all-in-one, easy-to-use localization and tracking system on low cost and commodity smartphones is first of its kind. Furthermore, smartphones' exclusive user-friendly interface has been effectively taken advantage of by our system to facilitate low complexity and high accuracy. Our experimental results show that our system works accurately and efficiently.

  16. [Sexuality and the human body: the subject's view through video images].

    Science.gov (United States)

    Vargas, E; Siqueira, V H

    1999-11-01

    This study analyzes images of the body linked to sexual and reproductive behavior found in the communication processes mediated by so-called educational videos. In the relationship between subject and technology, the paper is intended to characterize the discourses and the view or perspective currently shaping health education practices. Focusing on the potential in the relationship between the enunciator and subjects represented in the text and the interaction between health professionals and messages, the study attempts to characterize the discourses and questions providing the basis for a given view of the body and sexuality. The study was conducted in the years 1996-1997 and focused on health professionals from the public health system. The results show a concept of sexuality that tends to generalize the meaning ascribed to sexual experience, ignoring the various ways by which different culturally defined groups attribute meaning to the body.

  17. Three-dimensional tomographic imaging for dynamic radiation behavior study using infrared imaging video bolometers in large helical device plasma

    Energy Technology Data Exchange (ETDEWEB)

    Sano, Ryuichi; Iwama, Naofumi [National Institute for Fusion Science, 322-6 Oroshi-cho, Toki, Gifu 509-5292 (Japan); Peterson, Byron J.; Kobayashi, Masahiro; Mukai, Kiyofumi [National Institute for Fusion Science, 322-6 Oroshi-cho, Toki, Gifu 509-5292 (Japan); SOKENDAI (The Graduate University for Advanced Studies), Hayama, Kanagawa 240-0193 (Japan); Teranishi, Masaru [Hiroshima Institute of Technology, 2-1-1, Miyake, Saeki-ku, Hiroshima 731-5193 (Japan); Pandya, Shwetang N. [Institute of Plasma Research, Near Indira Bridge, Bhat Village, Gandhinagar, Gujarat 382428 (India)

    2016-05-15

    A three-dimensional (3D) tomography system using four InfraRed imaging Video Bolometers (IRVBs) has been designed with a helical periodicity assumption for the purpose of plasma radiation measurement in the large helical device. For the spatial inversion of large sized arrays, the system has been numerically and experimentally examined using the Tikhonov regularization with the criterion of minimum generalized cross validation, which is the standard solver of inverse problems. The 3D transport code EMC3-EIRENE for impurity behavior and related radiation has been used to produce phantoms for numerical tests, and the relative calibration of the IRVB images has been carried out with a simple function model of the decaying plasma in a radiation collapse. The tomography system can respond to temporal changes in the plasma profile and identify the 3D dynamic behavior of radiation, such as the radiation enhancement that starts from the inboard side of the torus, during the radiation collapse. The reconstruction results are also consistent with the output signals of a resistive bolometer. These results indicate that the designed 3D tomography system is available for the 3D imaging of radiation. The first 3D direct tomographic measurement of a magnetically confined plasma has been achieved.

  18. Abdominal MR imaging using a HASTE sequence : image comparison on the different echo times

    Energy Technology Data Exchange (ETDEWEB)

    Park, Kwang Bo; Lee, Moon Gyu; Lim, Tae Hwan; Jeong, Yoong Ki; Ha, Hyun Kwon; Kim, Pyo Nyun; Auh, Yong Ho [Ulsan Univ. College of Medicine, Asan Medical Center, Seoul (Korea, Republic of)

    1999-11-01

    To determine the optimal parameters of abdominal HASTE imaging by means of a comparison of intermediate and long TE (echo time). We evaluated 30 consecutive patients who had undergone liver MR during a three-month period. Twelve patients were diagnosed as normal, four as having liver cirrhosis, and 14 were found to be suffering form hepatic hemangioma. On the basis of measured signal intensity of the liver, spleen, pancreas and gallbladder, and of fat, muscle, hemangioma, and background, we calculated the ratios of signal to noise (S/N), signal difference to noise (SD/N), and signal intensity (SI). Image quality was compared using these three ratios, and using two HASTE sequences with TEs of 90 msec and 134 msec, images were qualitatively evaluated. S/N ratio of the liver was higher when TE was 90 msec(p<.05), though S/N, SD/N and SI rations of the spleen, gallbladder, and pancreas-and of hemangiom-were higher when TE was 134 msec (p<.05). However, in muscle, all these three ratios were higher at a TE of 90 msec. SD/N ratio and SI of fat were higher at a TE of 134 msec. Overall image quality was better at a TE of 134 msec than at one of 90msec. A HASTE sequence with a TE of 134msec showed greater tissue contrast and stronger T2-weighted images than one with a TE of 90msec.

  19. Capturing and displaying microscopic images used in medical diagnostics and forensic science using 4K video resolution – an application in higher education

    NARCIS (Netherlands)

    Jan Kuijten; Ajda Ortac; Hans Maier; Gert de Heer

    2015-01-01

    To analyze, interpret and evaluate microscopic images, used in medical diagnostics and forensic science, video images for educational purposes were made with a very high resolution of 4096 × 2160 pixels (4K), which is four times as many pixels as High-Definition Video (1920 × 1080 pixels).

  20. Real-time SPARSE-SENSE cardiac cine MR imaging: optimization of image reconstruction and sequence validation.

    Science.gov (United States)

    Goebel, Juliane; Nensa, Felix; Bomas, Bettina; Schemuth, Haemi P; Maderwald, Stefan; Gratz, Marcel; Quick, Harald H; Schlosser, Thomas; Nassenstein, Kai

    2016-12-01

    Improved real-time cardiac magnetic resonance (CMR) sequences have currently been introduced, but so far only limited practical experience exists. This study aimed at image reconstruction optimization and clinical validation of a new highly accelerated real-time cine SPARSE-SENSE sequence. Left ventricular (LV) short-axis stacks of a real-time free-breathing SPARSE-SENSE sequence with high spatiotemporal resolution and of a standard segmented cine SSFP sequence were acquired at 1.5 T in 11 volunteers and 15 patients. To determine the optimal iterations, all volunteers' SPARSE-SENSE images were reconstructed using 10-200 iterations, and contrast ratios, image entropies, and reconstruction times were assessed. Subsequently, the patients' SPARSE-SENSE images were reconstructed with the clinically optimal iterations. LV volumetric values were evaluated and compared between both sequences. Sufficient image quality and acceptable reconstruction times were achieved when using 80 iterations. Bland-Altman plots and Passing-Bablok regression showed good agreement for all volumetric parameters. 80 iterations are recommended for iterative SPARSE-SENSE image reconstruction in clinical routine. Real-time cine SPARSE-SENSE yielded comparable volumetric results as the current standard SSFP sequence. Due to its intrinsic low image acquisition times, real-time cine SPARSE-SENSE imaging with iterative image reconstruction seems to be an attractive alternative for LV function analysis. • A highly accelerated real-time CMR sequence using SPARSE-SENSE was evaluated. • SPARSE-SENSE allows free breathing in real-time cardiac cine imaging. • For clinically optimal SPARSE-SENSE image reconstruction, 80 iterations are recommended. • Real-time SPARSE-SENSE imaging yielded comparable volumetric results as the reference SSFP sequence. • The fast SPARSE-SENSE sequence is an attractive alternative to standard SSFP sequences.

  1. Review of passive-blind detection in digital video forgery based on sensing and imaging techniques

    Science.gov (United States)

    Tao, Junjie; Jia, Lili; You, Ying

    2016-01-01

    Advances in digital video compression and IP communication technologies raised new issues and challenges concerning the integrity and authenticity of surveillance videos. It is so important that the system should ensure that once recorded, the video cannot be altered; ensuring the audit trail is intact for evidential purposes. This paper gives an overview of passive techniques of Digital Video Forensics which are based on intrinsic fingerprints inherent in digital surveillance videos. In this paper, we performed a thorough research of literatures relevant to video manipulation detection methods which accomplish blind authentications without referring to any auxiliary information. We presents review of various existing methods in literature, and much more work is needed to be done in this field of video forensics based on video data analysis and observation of the surveillance systems.

  2. OPTIMISATION OF OCCUPATIONAL RADIATION PROTECTION IN IMAGE-GUIDED INTERVENTIONS: EXPLORING VIDEO RECORDINGS AS A TOOL IN THE PROCESS.

    Science.gov (United States)

    Almén, Anja; Sandblom, Viktor; Rystedt, Hans; von Wrangel, Alexa; Ivarsson, Jonas; Båth, Magnus; Lundh, Charlotta

    2016-06-01

    The overall purpose of this work was to explore how video recordings can contribute to the process of optimising occupational radiation protection in image-guided interventions. Video-recorded material from two image-guided interventions was produced and used to investigate to what extent it is conceivable to observe and assess dose-affecting actions in video recordings. Using the recorded material, it was to some extent possible to connect the choice of imaging techniques to the medical events during the procedure and, to a less extent, to connect these technical and medical issues to the occupational exposure. It was possible to identify a relationship between occupational exposure level to staff and positioning and use of shielding. However, detailed values of the dose rates were not possible to observe on the recordings, and the change in occupational exposure level from adjustments of exposure settings was not possible to identify. In conclusion, the use of video recordings is a promising tool to identify dose-affecting instances, allowing for a deeper knowledge of the interdependency between the management of the medical procedure, the applied imaging technology and the occupational exposure level. However, for a full information about the dose-affecting actions, the equipment used and the recording settings have to be thoroughly planned. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  3. Image Segmentation and Feature Extraction for Recognizing Strokes in Tennis Game Videos

    NARCIS (Netherlands)

    Zivkovic, Z.; van der Heijden, Ferdinand; Petkovic, M.; Jonker, Willem; Langendijk, R.L.; Heijnsdijk, J.W.J.; Pimentel, A.D.; Wilkinson, M.H.F.

    This paper addresses the problem of recognizing human actions from video. Particularly, the case of recognizing events in tennis game videos is analyzed. Driven by our domain knowledge, a robust player segmentation algorithm is developed for real video data. Further, we introduce a number of novel

  4. A High-Throughput and Low-Complexity H.264/AVC Intra 16×16 Prediction Architecture for HD Video Sequences

    Directory of Open Access Journals (Sweden)

    M. Orlandić

    2014-11-01

    Full Text Available H.264/AVC compression standard provides tools and solutions for an efficient coding of video sequences of various resolutions. Spatial redundancy in a video frame is removed by use of intra prediction algorithm. There are three block-wise types of intra prediction: 4×4, 8×8 and 16×16. This paper proposes an efficient, low-complexity architecture for intra 16×16 prediction that provides real-time processing of HD video sequences. All four prediction (V, H, DC, Plane modes are supported in the implementation. The high-complexity plane mode computes a number of intermediate parameters required for creating prediction pixels. The local memory buffers are used for storing intermediate reconstructed data used as reference pixels in intra prediction process. The high throughput is achieved by 16-pixel parallelism and the proposed prediction process takes 48 cycles for processing one macroblock. The proposed architecture is synthesized and implemented on Kintex 705 -XC7K325T board and requires 94 MHz to encode a video sequence of HD 4k×2k (3840×2160 resolution at 60 fps in real time. This represents a significant improvement compared to the state of the art.

  5. Video-rate in vivo fluorescence imaging with a line-scanned dual-axis confocal microscope

    Science.gov (United States)

    Chen, Ye; Wang, Danni; Khan, Altaz; Wang, Yu; Borwege, Sabine; Sanai, Nader; Liu, Jonathan T. C.

    2015-10-01

    Video-rate optical-sectioning microscopy of living organisms would allow for the investigation of dynamic biological processes and would also reduce motion artifacts, especially for in vivo imaging applications. Previous feasibility studies, with a slow stage-scanned line-scanned dual-axis confocal (LS-DAC) microscope, have demonstrated that LS-DAC microscopy is capable of imaging tissues with subcellular resolution and high contrast at moderate depths of up to several hundred microns. However, the sensitivity and performance of a video-rate LS-DAC imaging system, with low-numerical aperture optics, have yet to be demonstrated. Here, we report on the construction and validation of a video-rate LS-DAC system that possesses sufficient sensitivity to visualize fluorescent contrast agents that are topically applied or systemically delivered in animal and human tissues. We present images of murine oral mucosa that are topically stained with methylene blue, and images of protoporphyrin IX-expressing brain tumor from glioma patients that have been administered 5-aminolevulinic acid prior to surgery. In addition, we demonstrate in vivo fluorescence imaging of red blood cells trafficking within the capillaries of a mouse ear, at frame rates of up to 30 fps. These results can serve as a benchmark for miniature in vivo microscopy devices under development.

  6. A Review on Video/Image Authentication and Tamper Detection Techniques

    Science.gov (United States)

    Parmar, Zarna; Upadhyay, Saurabh

    2013-02-01

    With the innovations and development in sophisticated video editing technology and a wide spread of video information and services in our society, it is becoming increasingly significant to assure the trustworthiness of video information. Therefore in surveillance, medical and various other fields, video contents must be protected against attempt to manipulate them. Such malicious alterations could affect the decisions based on these videos. A lot of techniques are proposed by various researchers in the literature that assure the authenticity of video information in their own way. In this paper we present a brief survey on video authentication techniques with their classification. These authentication techniques are generally classified into following categories: digital signature based techniques, watermark based techniques, and other authentication techniques.

  7. CREATION OF 3D MODELS FROM LARGE UNSTRUCTURED IMAGE AND VIDEO DATASETS

    Directory of Open Access Journals (Sweden)

    J. Hollick

    2013-05-01

    Full Text Available Exploration of various places using low-cost camera solutions over decades without having a photogrammetric application in mind has resulted in large collections of images and videos that may have significant cultural value. The purpose of collecting this data is often to provide a log of events and therefore the data is often unstructured and of varying quality. Depending on the equipment used there may be approximate location data available for the images but the accuracy of this data may also be of varying quality. In this paper we present an approach that can deal with these conditions and process datasets of this type to produce 3D models. Results from processing the dataset collected during the discovery and subsequent exploration of the HMAS Sydney and HSK Kormoran wreck sites shows the potential of our approach. The results are promising and show that there is potential to retrieve significantly more information from many of these datasets than previously thought possible.

  8. Jointly optimized spatial prediction and block transform for video and image coding.

    Science.gov (United States)

    Han, Jingning; Saxena, Ankur; Melkote, Vinay; Rose, Kenneth

    2012-04-01

    This paper proposes a novel approach to jointly optimize spatial prediction and the choice of the subsequent transform in video and image compression. Under the assumption of a separable first-order Gauss-Markov model for the image signal, it is shown that the optimal Karhunen-Loeve Transform, given available partial boundary information, is well approximated by a close relative of the discrete sine transform (DST), with basis vectors that tend to vanish at the known boundary and maximize energy at the unknown boundary. The overall intraframe coding scheme thus switches between this variant of the DST named asymmetric DST (ADST), and traditional discrete cosine transform (DCT), depending on prediction direction and boundary information. The ADST is first compared with DCT in terms of coding gain under ideal model conditions and is demonstrated to provide significantly improved compression efficiency. The proposed adaptive prediction and transform scheme is then implemented within the H.264/AVC intra-mode framework and is experimentally shown to significantly outperform the standard intra coding mode. As an added benefit, it achieves substantial reduction in blocking artifacts due to the fact that the transform now adapts to the statistics of block edges. An integer version of this ADST is also proposed.

  9. An Algorithm for Pedestrian Detection in Multispectral Image Sequences

    Science.gov (United States)

    Kniaz, V. V.; Fedorenko, V. V.

    2017-05-01

    The growing interest for self-driving cars provides a demand for scene understanding and obstacle detection algorithms. One of the most challenging problems in this field is the problem of pedestrian detection. Main difficulties arise from a diverse appearances of pedestrians. Poor visibility conditions such as fog and low light conditions also significantly decrease the quality of pedestrian detection. This paper presents a new optical flow based algorithm BipedDetet that provides robust pedestrian detection on a single-borad computer. The algorithm is based on the idea of simplified Kalman filtering suitable for realization on modern single-board computers. To detect a pedestrian a synthetic optical flow of the scene without pedestrians is generated using slanted-plane model. The estimate of a real optical flow is generated using a multispectral image sequence. The difference of the synthetic optical flow and the real optical flow provides the optical flow induced by pedestrians. The final detection of pedestrians is done by the segmentation of the difference of optical flows. To evaluate the BipedDetect algorithm a multispectral dataset was collected using a mobile robot.

  10. Video-based face recognition via convolutional neural networks

    Science.gov (United States)

    Bao, Tianlong; Ding, Chunhui; Karmoshi, Saleem; Zhu, Ming

    2017-06-01

    Face recognition has been widely studied recently while video-based face recognition still remains a challenging task because of the low quality and large intra-class variation of video captured face images. In this paper, we focus on two scenarios of video-based face recognition: 1)Still-to-Video(S2V) face recognition, i.e., querying a still face image against a gallery of video sequences; 2)Video-to-Still(V2S) face recognition, in contrast to S2V scenario. A novel method was proposed in this paper to transfer still and video face images to an Euclidean space by a carefully designed convolutional neural network, then Euclidean metrics are used to measure the distance between still and video images. Identities of still and video images that group as pairs are used as supervision. In the training stage, a joint loss function that measures the Euclidean distance between the predicted features of training pairs and expanding vectors of still images is optimized to minimize the intra-class variation while the inter-class variation is guaranteed due to the large margin of still images. Transferred features are finally learned via the designed convolutional neural network. Experiments are performed on COX face dataset. Experimental results show that our method achieves reliable performance compared with other state-of-the-art methods.

  11. Significance of telemedicine for video image transmission of endoscopic retrograde cholangiopancreatography and endoscopic ultrasonography procedures.

    Science.gov (United States)

    Shimizu, Shuji; Itaba, Soichi; Yada, Shinichiro; Takahata, Shunichi; Nakashima, Naoki; Okamura, Koji; Rerknimitr, Rungsun; Akaraviputh, Thawatchai; Lu, Xinghua; Tanaka, Masao

    2011-05-01

    With the rapid and marked progress in gastrointestinal endoscopy, the education of doctors in many new diagnostic and therapeutic procedures is of increasing importance. Telecommunications (telemedicine) is very useful and cost-effective for doctors' continuing exposure to advanced skills, including those needed for hepato-pancreato-biliary diseases. Nevertheless, telemedicine in endoscopy has not yet gained much popularity. We have successfully established a new system which solves the problems of conventional ones, namely poor streaming images and the need for special expensive teleconferencing equipment. The digital video transport system, free software that transforms digital video signals directly into Internet Protocol without any analog conversion, was installed on a personal computer using a network with as much as 30 Mbps per channel, thereby providing more than 200 times greater information volume than the conventional system. Kyushu University Hospital in Japan was linked internationally to worldwide academic networks, using security software to protect patients' privacy. Of the 188 telecommunications link-ups involving 108 institutions in 23 countries performed between February 2003 and August 2009, 55 events were endoscopy-related, 19 were live demonstrations, and 36 were gastrointestinal teleconferences with interactive discussions. The frame rate of the transmitted pictures was 30/s, thus preserving smooth high-quality streaming. This paper documents the first time that an advanced tele-endoscopy system has been established over such a wide area using academic high-volume networks, funded by the various governments, and which is now available all over the world. The benefits of a network dedicated to research and education have barely been recognized in the medical community. We believe our cutting-edge system will be a milestone in endoscopy and will improve the quality of gastrointestinal education, especially with respect to endoscopic retrograde

  12. A framework for creating realistic synthetic fluorescence microscopy image sequences

    CSIR Research Space (South Africa)

    Mabaso, M

    2016-02-01

    Full Text Available Fluorescence microscopy imaging is an important tool in modern biological research, allowing insights into the processes of biological systems. Automated image analysis algorithms help in extracting information from these images. Validation...

  13. Video Salient Object Detection via Fully Convolutional Networks.

    Science.gov (United States)

    Wang, Wenguan; Shen, Jianbing; Shao, Ling

    This paper proposes a deep learning model to efficiently detect salient regions in videos. It addresses two important issues: 1) deep video saliency model training with the absence of sufficiently large and pixel-wise annotated video data and 2) fast video saliency training and detection. The proposed deep video saliency network consists of two modules, for capturing the spatial and temporal saliency information, respectively. The dynamic saliency model, explicitly incorporating saliency estimates from the static saliency model, directly produces spatiotemporal saliency inference without time-consuming optical flow computation. We further propose a novel data augmentation technique that simulates video training data from existing annotated image data sets, which enables our network to learn diverse saliency information and prevents overfitting with the limited number of training videos. Leveraging our synthetic video data (150K video sequences) and real videos, our deep video saliency model successfully learns both spatial and temporal saliency cues, thus producing accurate spatiotemporal saliency estimate. We advance the state-of-the-art on the densely annotated video segmentation data set (MAE of .06) and the Freiburg-Berkeley Motion Segmentation data set (MAE of .07), and do so with much improved speed (2 fps with all steps).This paper proposes a deep learning model to efficiently detect salient regions in videos. It addresses two important issues: 1) deep video saliency model training with the absence of sufficiently large and pixel-wise annotated video data and 2) fast video saliency training and detection. The proposed deep video saliency network consists of two modules, for capturing the spatial and temporal saliency information, respectively. The dynamic saliency model, explicitly incorporating saliency estimates from the static saliency model, directly produces spatiotemporal saliency inference without time-consuming optical flow computation. We further

  14. Endoscopic trimodal imaging detects colonic neoplasia as well as standard video endoscopy.

    Science.gov (United States)

    Kuiper, Teaco; van den Broek, Frank J C; Naber, Anton H; van Soest, Ellert J; Scholten, Pieter; Mallant-Hent, Rosalie Ch; van den Brande, Jan; Jansen, Jeroen M; van Oijen, Arnoud H A M; Marsman, Willem A; Bergman, Jacques J G H M; Fockens, Paul; Dekker, Evelien

    2011-06-01

    Endoscopic trimodal imaging (ETMI) is a novel endoscopic technique that combines high-resolution endoscopy (HRE), autofluorescence imaging (AFI), and narrow-band imaging (NBI) that has only been studied in academic settings. We performed a randomized, controlled trial in a nonacademic setting to compare ETMI with standard video endoscopy (SVE) in the detection and differentiation of colorectal lesions. The study included 234 patients scheduled to receive colonoscopy who were randomly assigned to undergo a colonoscopy in tandem with either ETMI or SVE. In the ETMI group (n=118), first examination was performed using HRE, followed by AFI. In the other group, both examinations were performed using SVE (n=116). In the ETMI group, detected lesions were differentiated using AFI and NBI. In the ETMI group, 87 adenomas were detected in the first examination (with HRE), and then 34 adenomas were detected during second inspection (with AFI). In the SVE group, 79 adenomas were detected during the first inspection, and then 33 adenomas were detected during the second inspection. Adenoma detection rates did not differ significantly between the 2 groups (ETMI: 1.03 vs SVE: 0.97, P=.360). The adenoma miss-rate was 29% for HRE and 28% for SVE. The sensitivity, specificity, and accuracy of NBI in differentiating adenomas from nonadenomatous lesions were 87%, 63%, and 75%, respectively; corresponding values for AFI were 90%, 37%, and 62%, respectively. In a nonacademic setting, ETMI did not improve the detection rate for adenomas compared with SVE. NBI and AFI each differentiated colonic lesions with high levels of sensitivity but low levels of specificity. Copyright © 2011 AGA Institute. Published by Elsevier Inc. All rights reserved.

  15. Fast Aerial Video Stitching

    Directory of Open Access Journals (Sweden)

    Jing Li

    2014-10-01

    Full Text Available The highly efficient and robust stitching of aerial video captured by unmanned aerial vehicles (UAVs is a challenging problem in the field of robot vision. Existing commercial image stitching systems have seen success with offline stitching tasks, but they cannot guarantee high-speed performance when dealing with online aerial video sequences. In this paper, we present a novel system which has an unique ability to stitch high-frame rate aerial video at a speed of 150 frames per second (FPS. In addition, rather than using a high-speed vision platform such as FPGA or CUDA, our system is running on a normal personal computer. To achieve this, after the careful comparison of the existing invariant features, we choose the FAST corner and binary descriptor for efficient feature extraction and representation, and present a spatial and temporal coherent filter to fuse the UAV motion information into the feature matching. The proposed filter can remove the majority of feature correspondence outliers and significantly increase the speed of robust feature matching by up to 20 times. To achieve a balance between robustness and efficiency, a dynamic key frame-based stitching framework is used to reduce the accumulation errors. Extensive experiments on challenging UAV datasets demonstrate that our approach can break through the speed limitation and generate an accurate stitching image for aerial video stitching tasks.

  16. Real-time video imaging of gas plumes using a DMD-enabled full-frame programmable spectral filter

    Science.gov (United States)

    Graff, David L.; Love, Steven P.

    2016-02-01

    Programmable spectral filters based on digital micromirror devices (DMDs) are typically restricted to imaging a 1D line across a scene, analogous to conventional "push-broom scanning" hyperspectral imagers. In previous work, however, we demonstrated that, by placing the diffraction grating at a telecentric image plane rather than at the more conventional location in collimated space, a spectral plane can be created at which light from the entire 2D scene focuses to a unique location for each wavelength. A DMD placed at this spectral plane can then spectrally manipulate an entire 2D image at once, enabling programmable matched filters to be applied to real-time video imaging. We have adapted this concept to imaging rapidly evolving gas plumes. We have constructed a high spectral resolution programmable spectral imager operating in the shortwave infrared region, capable of resolving the rotational-vibrational line structure of several gases at sub-nm spectral resolution. This ability to resolve the detailed gas-phase line structure enables implementation of highly selective filters that unambiguously separate the gas spectrum from background spectral clutter. On-line and between-line multi-band spectral filters, with bands individually weighted using the DMD's duty-cycle-based grayscale capability, are alternately uploaded to the DMD, the resulting images differenced, and the result displayed in real time at rates of several frames per second to produce real-time video of the turbulent motion of the gas plume.

  17. A clinical pilot study of a modular video-CT augmentation system for image-guided skull base surgery

    Science.gov (United States)

    Liu, Wen P.; Mirota, Daniel J.; Uneri, Ali; Otake, Yoshito; Hager, Gregory; Reh, Douglas D.; Ishii, Masaru; Gallia, Gary L.; Siewerdsen, Jeffrey H.

    2012-02-01

    Augmentation of endoscopic video with preoperative or intraoperative image data [e.g., planning data and/or anatomical segmentations defined in computed tomography (CT) and magnetic resonance (MR)], can improve navigation, spatial orientation, confidence, and tissue resection in skull base surgery, especially with respect to critical neurovascular structures that may be difficult to visualize in the video scene. This paper presents the engineering and evaluation of a video augmentation system for endoscopic skull base surgery translated to use in a clinical study. Extension of previous research yielded a practical system with a modular design that can be applied to other endoscopic surgeries, including orthopedic, abdominal, and thoracic procedures. A clinical pilot study is underway to assess feasibility and benefit to surgical performance by overlaying CT or MR planning data in realtime, high-definition endoscopic video. Preoperative planning included segmentation of the carotid arteries, optic nerves, and surgical target volume (e.g., tumor). An automated camera calibration process was developed that demonstrates mean re-projection accuracy (0.7+/-0.3) pixels and mean target registration error of (2.3+/-1.5) mm. An IRB-approved clinical study involving fifteen patients undergoing skull base tumor surgery is underway in which each surgery includes the experimental video-CT system deployed in parallel to the standard-of-care (unaugmented) video display. Questionnaires distributed to one neurosurgeon and two otolaryngologists are used to assess primary outcome measures regarding the benefit to surgical confidence in localizing critical structures and targets by means of video overlay during surgical approach, resection, and reconstruction.

  18. NEI You Tube Videos: Amblyopia

    Medline Plus

    Full Text Available ... questions Clinical Studies Publications Catalog Photos and Images Spanish Language Information Grants and Funding Extramural Research Division ... Low Vision Refractive Errors Retinopathy of Prematurity Science Spanish Videos Webinars NEI YouTube Videos: Amblyopia Embedded video ...

  19. Multisensor fusion in gastroenterology domain through video and echo endoscopic image combination: a challenge

    Science.gov (United States)

    Debon, Renaud; Le Guillou, Clara; Cauvin, Jean-Michel; Solaiman, Basel; Roux, Christian

    2001-08-01

    Medical domain makes intensive use of information fusion. In particular, the gastro-enterology is a discipline where physicians have the choice between several imagery modalities that offer complementary advantages. Among all existing systems, videoendoscopy (based on a CCD sensor) and echoendoscopy (based on an ultrasound sensor) are the most efficient. The use of each system corresponds to a given step in the physician diagnostic elaboration. Nowadays, several works aim to achieve automatic interpretation of videoendoscopic sequences. These systems can quantify color and superficial textures of the digestive tube. Unfortunately the relief information, which is important for the diagnostic, is very difficult to retrieve. On the other hand, some studies have proved that 3D information can be easily quantified using echoendoscopy image sequences. That is why the idea to combine these information, acquired from two very different points of view, can be considered as a real challenge for the medical image fusion topic. In this paper, after a review of actual works concerning numerical exploitation of videoendoscopy and echoendoscopy, the following question will be discussed: how can the use of complementary aspects of the different systems ease the automatic exploitation of videoendoscopy ? In a second time, we will evaluate the feasibility of the achievement of a realistic 3D reconstruction based both on information given by echoendoscopy (relief) and videoendoscopy (texture). Enumeration of potential applications of such a fusion system will then follow. Further discussions and perspectives will conclude this first study.

  20. Prediction of foal carcass composition and wholesale cut yields by using video image analysis.

    Science.gov (United States)

    Lorenzo, J M; Guedes, C M; Agregán, R; Sarriés, M V; Franco, D; Silva, S R

    2018-01-01

    This work represents the first contribution for the application of the video image analysis (VIA) technology in predicting lean meat and fat composition in the equine species. Images of left sides of the carcass (n=42) were captured from the dorsal, lateral and medial views using a high-resolution digital camera. A total of 41 measurements (angles, lengths, widths and areas) were obtained by VIA. The variation of percentage of lean meat obtained from the forequarter (FQ) and hindquarter (HQ) carcass ranged between 5.86% and 7.83%. However, the percentage of fat (FAT) obtained from the FQ and HQ carcass presented a higher variation (CV between 41.34% and 44.58%). By combining different measurements and using prediction models with cold carcass weight (CCW) and VIA measurement the coefficient of determination (k-fold-R 2) were 0.458 and 0.532 for FQ and HQ, respectively. On the other hand, employing the most comprehensive model (CCW plus all VIA measurements), the k-fold-R 2 increased from 0.494 to 0.887 and 0.513 to 0.878 with respect to the simplest model (only with CCW), while precision increased with the reduction in the root mean square error (2.958 to 0.947 and 1.841 to 0.787) for the hindquarter fat and lean percentage, respectively. With CCW plus VIA measurements is possible to explain the wholesale value cuts yield variation (k-fold-R 2 between 0.533 and 0.889). Overall, the VIA technology performed in the present study could be considered as an accurate method to assess the horse carcass composition which could have a role in breeding programmes and research studies to assist in the development of a value-based marketing system for horse carcass.

  1. Quantitative sodium imaging with a flexible twisted projection pulse sequence

    National Research Council Canada - National Science Library

    Lu, Aiming; Atkinson, Ian C; Claiborne, Theodore C; Damen, Frederick C; Thulborn, Keith R

    2010-01-01

    The quantification of sodium MR images from an arbitrary intensity scale into a bioscale fosters image interpretation in terms of the spatially resolved biochemical process of sodium ion homeostasis...

  2. Performance of Correspondence Algorithms in Vision-Based Driver Assistance Using an Online Image Sequence Database

    DEFF Research Database (Denmark)

    Klette, Reinhard; Krüger, Norbert; Vaudrey, Tobi

    2011-01-01

    This paper discusses options for testing correspondence algorithms in stereo or motion analysis that are designed or considered for vision-based driver assistance. It introduces a globally available database, with a main focus on testing on video sequences of real-world data. We suggest...... the classification of recorded video data into situations defined by a cooccurrence of some events in recorded traffic scenes. About 100-400 stereo frames (or 4-16 s of recording) are considered a basic sequence, which will be identified with one particular situation. Future testing is expected to be on data......) for demonstrating ideas, difficulties, and possible ways in this future field of extensive performance tests in vision-based driver assistance, particularly for cases where the ground truth is not available. This paper shows that the complexity of real-world data does not support the identification of general...

  3. VideoSAR collections to image underground chemical explosion surface phenomena

    Science.gov (United States)

    Yocky, David A.; Calloway, Terry M.; Wahl, Daniel E.

    2017-05-01

    Fully-polarimetric X-band (9.6 GHz center frequency) VideoSAR with 0.125-meter ground resolution flew collections before, during, and after the fifth Source Physics Experiment (SPE-5) underground chemical explosion. We generate and exploit synthetic aperture RADAR (SAR) and VideoSAR products to characterize surface effects caused by the underground explosion. To our knowledge, this has never been done. Exploited VideoSAR products are "movies" of coherence maps, phase-difference maps, and magnitude imagery. These movies show two-dimensional, time-varying surface movement. However, objects located on the SPE pad created unwanted, vibrating signatures during the event which made registration and coherent processing more difficult. Nevertheless, there is evidence that dynamic changes are captured by VideoSAR during the event. VideoSAR provides a unique, coherent, time-varying measure of surface expression of an underground chemical explosion.

  4. Short term exposure to attractive and muscular singers in music video clips negatively affects men's body image and mood.

    Science.gov (United States)

    Mulgrew, K E; Volcevski-Kostas, D

    2012-09-01

    Viewing idealized images has been shown to reduce men's body satisfaction; however no research has examined the impact of music video clips. This was the first study to examine the effects of exposure to muscular images in music clips on men's body image, mood and cognitions. Ninety men viewed 5 min of clips containing scenery, muscular or average-looking singers, and completed pre- and posttest measures of mood and body image. Appearance schema activation was also measured. Men exposed to the muscular clips showed poorer posttest levels of anger, body and muscle tone satisfaction compared to men exposed to the scenery or average clips. No evidence of schema activation was found, although potential problems with the measure are noted. These preliminary findings suggest that even short term exposure to music clips can produce negative effects on men's body image and mood. Copyright © 2012 Elsevier Ltd. All rights reserved.

  5. Spatiotonal adaptivity in super-resolution of under-sampled image sequences

    NARCIS (Netherlands)

    Pham, T.Q.

    2006-01-01

    This thesis concerns the use of spatial and tonal adaptivity in improving the resolution of aliased image sequences under scene or camera motion. Each of the five content chapters focuses on a different subtopic of super-resolution: image registration (chapter 2), image fusion (chapter 3 and 4),

  6. Interactive video algorithms and technologies

    CERN Document Server

    Hammoud, Riad

    2006-01-01

    This book covers both algorithms and technologies of interactive videos, so that businesses in IT and data managements, scientists and software engineers in video processing and computer vision, coaches and instructors that use video technology in teaching, and finally end-users will greatly benefit from it. This book contains excellent scientific contributions made by a number of pioneering scientists and experts from around the globe. It consists of five parts. The first part introduces the reader to interactive video and video summarization and presents effective methodologies for automatic abstraction of a single video sequence, a set of video sequences, and a combined audio-video sequence. In the second part, a list of advanced algorithms and methodologies for automatic and semi-automatic analysis and editing of audio-video documents are presented. The third part tackles a more challenging level of automatic video re-structuring, filtering of video stream by extracting of highlights, events, and meaningf...

  7. A low-light-level video recursive filtering technology based on the three-dimensional coefficients

    Science.gov (United States)

    Fu, Rongguo; Feng, Shu; Shen, Tianyu; Luo, Hao; Wei, Yifang; Yang, Qi

    2017-08-01

    Low light level video is an important method of observation under low illumination condition, but the SNR of low light level video is low, the effect of observation is poor, so the noise reduction processing must be carried out. Low light level video noise mainly includes Gauss noise, Poisson noise, impulse noise, fixed pattern noise and dark current noise. In order to remove the noise in low-light-level video effectively, improve the quality of low-light-level video. This paper presents an improved time domain recursive filtering algorithm with three dimensional filtering coefficients. This algorithm makes use of the correlation between the temporal domain of the video sequence. In the video sequences, the proposed algorithm adaptively adjusts the local window filtering coefficients in space and time by motion estimation techniques, for the different pixel points of the same frame of the image, the different weighted coefficients are used. It can reduce the image tail, and ensure the noise reduction effect well. Before the noise reduction, a pretreatment based on boxfilter is used to reduce the complexity of the algorithm and improve the speed of the it. In order to enhance the visual effect of low-light-level video, an image enhancement algorithm based on guided image filter is used to enhance the edge of the video details. The results of experiment show that the hybrid algorithm can remove the noise of the low-light-level video effectively, enhance the edge feature and heighten the visual effects of video.

  8. Disembodied perspective: third-person images in GoPro videos

    National Research Council Canada - National Science Library

    Bédard, Philippe

    2015-01-01

    A technical analysis of GoPro videos, focusing on the production of a third-person perspective created when the camera is turned back on the user, and the sense of disorientation that results for the spectator...

  9. Estimating age ratios and size of pacific walrus herds on coastal haulouts using video imaging.

    Directory of Open Access Journals (Sweden)

    Daniel H Monson

    Full Text Available During Arctic summers, sea ice provides resting habitat for Pacific walruses as it drifts over foraging areas in the eastern Chukchi Sea. Climate-driven reductions in sea ice have recently created ice-free conditions in the Chukchi Sea by late summer causing walruses to rest at coastal haulouts along the Chukotka and Alaska coasts, which provides an opportunity to study walruses at relatively accessible locations. Walrus age can be determined from the ratio of tusk length to snout dimensions. We evaluated use of images obtained from a gyro-stabilized video system mounted on a helicopter flying at high altitudes (to avoid disturbance to classify the sex and age of walruses hauled out on Alaska beaches in 2010-2011. We were able to classify 95% of randomly selected individuals to either an 8- or 3-category age class, and we found measurement-based age classifications were more repeatable than visual classifications when using images presenting the correct head profile. Herd density at coastal haulouts averaged 0.88 walruses/m(2 (std. err. = 0.02, herd size ranged from 8,300 to 19,400 (CV 0.03-0.06 and we documented ∼30,000 animals along ∼1 km of beach in 2011. Within the herds, dependent walruses (0-2 yr-olds tended to be located closer to water, and this tendency became more pronounced as the herd spent more time on the beach. Therefore, unbiased estimation of herd age-ratios will require a sampling design that allows for spatial and temporal structuring. In addition, randomly sampling walruses available at the edge of the herd for other purposes (e.g., tagging, biopsying will not sample walruses with an age structure representative of the herd. Sea ice losses are projected to continue, and population age structure data collected with aerial videography at coastal haulouts may provide demographic information vital to ongoing efforts to understand effects of climate change on this species.

  10. Estimating age ratios and size of Pacific walrus herds on coastal haulouts using video imaging

    Science.gov (United States)

    Monson, Daniel H.; Udevitz, Mark S.; Jay, Chadwick V.

    2013-01-01

    During Arctic summers, sea ice provides resting habitat for Pacific walruses as it drifts over foraging areas in the eastern Chukchi Sea. Climate-driven reductions in sea ice have recently created ice-free conditions in the Chukchi Sea by late summer causing walruses to rest at coastal haulouts along the Chukotka and Alaska coasts, which provides an opportunity to study walruses at relatively accessible locations. Walrus age can be determined from the ratio of tusk length to snout dimensions. We evaluated use of images obtained from a gyro-stabilized video system mounted on a helicopter flying at high altitudes (to avoid disturbance) to classify the sex and age of walruses hauled out on Alaska beaches in 2010–2011. We were able to classify 95% of randomly selected individuals to either an 8- or 3-category age class, and we found measurement-based age classifications were more repeatable than visual classifications when using images presenting the correct head profile. Herd density at coastal haulouts averaged 0.88 walruses/m2 (std. err. = 0.02), herd size ranged from 8,300 to 19,400 (CV 0.03–0.06) and we documented ~30,000 animals along ~1 km of beach in 2011. Within the herds, dependent walruses (0–2 yr-olds) tended to be located closer to water, and this tendency became more pronounced as the herd spent more time on the beach. Therefore, unbiased estimation of herd age-ratios will require a sampling design that allows for spatial and temporal structuring. In addition, randomly sampling walruses available at the edge of the herd for other purposes (e.g., tagging, biopsying) will not sample walruses with an age structure representative of the herd. Sea ice losses are projected to continue, and population age structure data collected with aerial videography at coastal haulouts may provide demographic information vital to ongoing efforts to understand effects of climate change on this species.

  11. Estimating age ratios and size of pacific walrus herds on coastal haulouts using video imaging.

    Science.gov (United States)

    Monson, Daniel H; Udevitz, Mark S; Jay, Chadwick V

    2013-01-01

    During Arctic summers, sea ice provides resting habitat for Pacific walruses as it drifts over foraging areas in the eastern Chukchi Sea. Climate-driven reductions in sea ice have recently created ice-free conditions in the Chukchi Sea by late summer causing walruses to rest at coastal haulouts along the Chukotka and Alaska coasts, which provides an opportunity to study walruses at relatively accessible locations. Walrus age can be determined from the ratio of tusk length to snout dimensions. We evaluated use of images obtained from a gyro-stabilized video system mounted on a helicopter flying at high altitudes (to avoid disturbance) to classify the sex and age of walruses hauled out on Alaska beaches in 2010-2011. We were able to classify 95% of randomly selected individuals to either an 8- or 3-category age class, and we found measurement-based age classifications were more repeatable than visual classifications when using images presenting the correct head profile. Herd density at coastal haulouts averaged 0.88 walruses/m(2) (std. err. = 0.02), herd size ranged from 8,300 to 19,400 (CV 0.03-0.06) and we documented ∼30,000 animals along ∼1 km of beach in 2011. Within the herds, dependent walruses (0-2 yr-olds) tended to be located closer to water, and this tendency became more pronounced as the herd spent more time on the beach. Therefore, unbiased estimation of herd age-ratios will require a sampling design that allows for spatial and temporal structuring. In addition, randomly sampling walruses available at the edge of the herd for other purposes (e.g., tagging, biopsying) will not sample walruses with an age structure representative of the herd. Sea ice losses are projected to continue, and population age structure data collected with aerial videography at coastal haulouts may provide demographic information vital to ongoing efforts to understand effects of climate change on this species.

  12. Miniature stereoscopic video system provides real-time 3D registration and image fusion for minimally invasive surgery

    Science.gov (United States)

    Yaron, Avi; Bar-Zohar, Meir; Horesh, Nadav

    2007-02-01

    Sophisticated surgeries require the integration of several medical imaging modalities, like MRI and CT, which are three-dimensional. Many efforts are invested in providing the surgeon with this information in an intuitive & easy to use manner. A notable development, made by Visionsense, enables the surgeon to visualize the scene in 3D using a miniature stereoscopic camera. It also provides real-time 3D measurements that allow registration of navigation systems as well as 3D imaging modalities, overlaying these images on the stereoscopic video image in real-time. The real-time MIS 'see through tissue' fusion solutions enable the development of new MIS procedures in various surgical segments, such as spine, abdomen, cardio-thoracic and brain. This paper describes 3D surface reconstruction and registration methods using Visionsense camera, as a step toward fully automated multi-modality 3D registration.

  13. EFFICIENT USE OF VIDEO FOR 3D MODELLING OF CULTURAL HERITAGE OBJECTS

    Directory of Open Access Journals (Sweden)

    B. Alsadik

    2015-03-01

    Full Text Available Currently, there is a rapid development in the techniques of the automated image based modelling (IBM, especially in advanced structure-from-motion (SFM and dense image matching methods, and camera technology. One possibility is to use video imaging to create 3D reality based models of cultural heritage architectures and monuments. Practically, video imaging is much easier to apply when compared to still image shooting in IBM techniques because the latter needs a thorough planning and proficiency. However, one is faced with mainly three problems when video image sequences are used for highly detailed modelling and dimensional survey of cultural heritage objects. These problems are: the low resolution of video images, the need to process a large number of short baseline video images and blur effects due to camera shake on a significant number of images. In this research, the feasibility of using video images for efficient 3D modelling is investigated. A method is developed to find the minimal significant number of video images in terms of object coverage and blur effect. This reduction in video images is convenient to decrease the processing time and to create a reliable textured 3D model compared with models produced by still imaging. Two experiments for modelling a building and a monument are tested using a video image resolution of 1920×1080 pixels. Internal and external validations of the produced models are applied to find out the final predicted accuracy and the model level of details. Related to the object complexity and video imaging resolution, the tests show an achievable average accuracy between 1 – 5 cm when using video imaging, which is suitable for visualization, virtual museums and low detailed documentation.

  14. CT image sequence restoration based on sparse and low-rank decomposition.

    Directory of Open Access Journals (Sweden)

    Shuiping Gou

    Full Text Available Blurry organ boundaries and soft tissue structures present a major challenge in biomedical image restoration. In this paper, we propose a low-rank decomposition-based method for computed tomography (CT image sequence restoration, where the CT image sequence is decomposed into a sparse component and a low-rank component. A new point spread function of Weiner filter is employed to efficiently remove blur in the sparse component; a wiener filtering with the Gaussian PSF is used to recover the average image of the low-rank component. And then we get the recovered CT image sequence by combining the recovery low-rank image with all recovery sparse image sequence. Our method achieves restoration results with higher contrast, sharper organ boundaries and richer soft tissue structure information, compared with existing CT image restoration methods. The robustness of our method was assessed with numerical experiments using three different low-rank models: Robust Principle Component Analysis (RPCA, Linearized Alternating Direction Method with Adaptive Penalty (LADMAP and Go Decomposition (GoDec. Experimental results demonstrated that the RPCA model was the most suitable for the small noise CT images whereas the GoDec model was the best for the large noisy CT images.

  15. CT image sequence restoration based on sparse and low-rank decomposition.

    Science.gov (United States)

    Gou, Shuiping; Wang, Yueyue; Wang, Zhilong; Peng, Yong; Zhang, Xiaopeng; Jiao, Licheng; Wu, Jianshe

    2013-01-01

    Blurry organ boundaries and soft tissue structures present a major challenge in biomedical image restoration. In this paper, we propose a low-rank decomposition-based method for computed tomography (CT) image sequence restoration, where the CT image sequence is decomposed into a sparse component and a low-rank component. A new point spread function of Weiner filter is employed to efficiently remove blur in the sparse component; a wiener filtering with the Gaussian PSF is used to recover the average image of the low-rank component. And then we get the recovered CT image sequence by combining the recovery low-rank image with all recovery sparse image sequence. Our method achieves restoration results with higher contrast, sharper organ boundaries and richer soft tissue structure information, compared with existing CT image restoration methods. The robustness of our method was assessed with numerical experiments using three different low-rank models: Robust Principle Component Analysis (RPCA), Linearized Alternating Direction Method with Adaptive Penalty (LADMAP) and Go Decomposition (GoDec). Experimental results demonstrated that the RPCA model was the most suitable for the small noise CT images whereas the GoDec model was the best for the large noisy CT images.

  16. Real-time intravascular photoacoustic-ultrasound imaging of lipid-laden plaque at speed of video-rate level

    Science.gov (United States)

    Hui, Jie; Cao, Yingchun; Zhang, Yi; Kole, Ayeeshik; Wang, Pu; Yu, Guangli; Eakins, Gregory; Sturek, Michael; Chen, Weibiao; Cheng, Ji-Xin

    2017-03-01

    Intravascular photoacoustic-ultrasound (IVPA-US) imaging is an emerging hybrid modality for the detection of lipidladen plaques by providing simultaneous morphological and lipid-specific chemical information of an artery wall. The clinical utility of IVPA-US technology requires real-time imaging and display at speed of video-rate level. Here, we demonstrate a compact and portable IVPA-US system capable of imaging at up to 25 frames per second in real-time display mode. This unprecedented imaging speed was achieved by concurrent innovations in excitation laser source, rotary joint assembly, 1 mm IVPA-US catheter, differentiated A-line strategy, and real-time image processing and display algorithms. By imaging pulsatile motion at different imaging speeds, 16 frames per second was deemed to be adequate to suppress motion artifacts from cardiac pulsation for in vivo applications. Our lateral resolution results further verified the number of A-lines used for a cross-sectional IVPA image reconstruction. The translational capability of this system for the detection of lipid-laden plaques was validated by ex vivo imaging of an atherosclerotic human coronary artery at 16 frames per second, which showed strong correlation to gold-standard histopathology.

  17. Simulation and Efficient Measurements of Intensities for Complex Imaging Sequences

    DEFF Research Database (Denmark)

    Jensen, Jørgen Arendt; Rasmussen, Morten Fischer; Stuart, Matthias Bo

    2014-01-01

    It is investigated how linear simulation can be used to predict both the magnitude of the intensities as well as the placement of the peak values. An ultrasound sequence is defined through the normal setup routines for the experimental SARUS scanner, and Field II is then used automatically on the...

  18. Elimination of motion and pulsation artifacts using BLADE sequences in shoulder MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Lavdas, E.; Zaloni, E. [Technological Education Institute of Athens, Greece, Department of Medical Radiological Technologists, Athens (Greece); Vlychou, M.; Vassiou, K.; Fezoulidis, I. [University of Thessaly, Department of Radiology, Faculty of Medicine, Larissa (Greece); Tsagkalis, A. [IASO Hospital, Department of Orthopedics, Larissa (Greece); Dailiana, Z. [University of Thessaly, Department of Orthopedics, Faculty of Medicine, Larissa (Greece)

    2015-11-15

    To evaluate the ability of proton-density with fat-suppression BLADE (proprietary name for periodically rotated overlapping parallel lines with enhanced reconstruction in MR systems from Siemens Healthcare, PDFS BLADE) and turbo inversion recovery magnitude-BLADE (TIRM BLADE) sequences to reduce motion and pulsation artifacts in shoulder magnetic resonance examinations. Forty-one consecutive patients who had been routinely scanned for shoulder examination participated in the study. The following pairs of sequences with and without BLADE were compared: (a) Oblique coronal proton-density sequence with fat saturation of 25 patients and (b) oblique sagittal T2 TIRM-weighed sequence of 20 patients. Qualitative analysis was performed by two experienced radiologists. Image motion and pulsation artifacts were also evaluated. In oblique coronal PDFS BLADE sequences, motion artifacts have been significantly eliminated, even in five cases of non-diagnostic value with conventional imaging. Similarly, in oblique sagittal T2 TIRM BLADE sequences, image quality has been improved, even in six cases of non-diagnostic value with conventional imaging. Furthermore, flow artifacts have been improved in more than 80% of all the cases. The use of BLADE sequences is recommended in shoulder imaging, especially in uncooperative patients because it effectively eliminates motion and pulsation artifacts. (orig.)

  19. Motion Estimation Using the Firefly Algorithm in Ultrasonic Image Sequence of Soft Tissue

    Directory of Open Access Journals (Sweden)

    Chih-Feng Chao

    2015-01-01

    Full Text Available Ultrasonic image sequence of the soft tissue is widely used in disease diagnosis; however, the speckle noises usually influenced the image quality. These images usually have a low signal-to-noise ratio presentation. The phenomenon gives rise to traditional motion estimation algorithms that are not suitable to measure the motion vectors. In this paper, a new motion estimation algorithm is developed for assessing the velocity field of soft tissue in a sequence of ultrasonic B-mode images. The proposed iterative firefly algorithm (IFA searches for few candidate points to obtain the optimal motion vector, and then compares it to the traditional iterative full search algorithm (IFSA via a series of experiments of in vivo ultrasonic image sequences. The experimental results show that the IFA can assess the vector with better efficiency and almost equal estimation quality compared to the traditional IFSA method.

  20. Peri-operative imaging of cancer margins with reflectance confocal microscopy during Mohs micrographic surgery: feasibility of a video-mosaicing algorithm

    Science.gov (United States)

    Flores, Eileen; Yelamos, Oriol; Cordova, Miguel; Kose, Kivanc; Phillips, William; Rossi, Anthony; Nehal, Kishwer; Rajadhyaksha, Milind

    2017-02-01

    Reflectance confocal microscopy (RCM) imaging shows promise for guiding surgical treatment of skin cancers. Recent technological advancements such as the introduction of the handheld version of the reflectance confocal microscope, video acquisition and video-mosaicing have improved RCM as an emerging tool to evaluate cancer margins during routine surgical skin procedures such as Mohs micrographic surgery (MMS). Detection of residual non-melanoma skin cancer (NMSC) tumor during MMS is feasible, as demonstrated by the introduction of real-time perioperative imaging on patients in the surgical setting. Our study is currently testing the feasibility of a new mosaicing algorithm for perioperative RCM imaging of NMSC cancer margins on patients during MMS. We report progress toward imaging and image analysis on forty-five patients, who presented for MMS at the MSKCC Dermatology service. The first 10 patients were used as a training set to establish an RCM imaging algorithm, which was implemented on the remaining test set of 35 patients. RCM imaging, using 35% AlCl3 for nuclear contrast, was performed pre- and intra-operatively with the Vivascope 3000 (Caliber ID). Imaging was performed in quadrants in the wound, to simulate the Mohs surgeon's examination of pathology. Videos were taken at the epidermal and deep dermal margins. Our Mohs surgeons assessed all videos and video-mosaics for quality and correlation to histology. Overall, our RCM video-mosaicing algorithm is feasible. RCM videos and video-mosaics of the epidermal and dermal margins were found to be of clinically acceptable quality. Assessment of cancer margins was affected by type of NMSC, size and location. Among the test set of 35 patients, 83% showed acceptable imaging quality, resolution and contrast. Visualization of nuclear and cellular morphology of residual BCC/SCC tumor and normal skin features could be detected in the peripheral and deep dermal margins. We observed correlation between the RCM videos/video

  1. Real-Depth imaging: a new 3D imaging technology with inexpensive direct-view (no glasses) video and other applications

    Science.gov (United States)

    Dolgoff, Eugene

    1997-05-01

    Floating Images, Inc. has developed the software and hardware for a new, patent pending, 'floating 3-D, off-the-screen- experience' display technology. This technology has the potential to become the next standard for home and arcade video games, computers, corporate presentations, Internet/Intranet viewing, and television. Current '3-D graphics' technologies are actually flat on screen. Floating ImagesTM technology actually produce images at different depths from any display, such as CRT and LCD, for television, computer, projection, and other formats. In addition, unlike stereoscopic 3-D imaging, no glasses, headgear, or other viewing aids are used. And, unlike current autostereoscopic imaging technologies, there is virtually no restriction on where viewers can sit to view the images, with no 'bad' or 'dead' zones, flipping, or pseudoscopy. In addition to providing traditional depth cues such as perspective and background image occlusion, the new technology also provides both horizontal and vertical binocular parallax (the ability to look around foreground objects to see previously hidden background objects, with each eye seeing a different view at all times) and accommodation (the need to re-focus one's eyes when shifting attention from a near object to a distant object) which coincides with convergence (the need to re-aim one's eyes when shifting attention from a near object to a distant object). Since accommodation coincides with convergence, viewing these images doesn't produce headaches, fatigue, or eye-strain, regardless of how long they are viewed (unlike stereoscopic and autostereoscopic displays). The imagery (video or computer generated) must either be formatted for the Floating ImagesTM platform when written or existing software can be re-formatted without much difficulty.

  2. Usefulness of the SPACE pulse sequence at 1.5T MR cholangiography: comparison of image quality and image acquisition time with conventional 3D-TSE sequence.

    Science.gov (United States)

    Nakaura, Takeshi; Kidoh, Masafumi; Maruyama, Natsuki; Kawahara, Tetsuya; Namimoto, Tomohiro; Sakai, Yoshinari; Harada, Kazunori; Yamashita, Yasuyuki

    2013-11-01

    To prospectively evaluate the image quality and image acquisition time at 3D magnetic resonance cholangiopancreatography (MRCP) using sampling perfection with application optimized contrasts (SPACE) and conventional turbo-spin-echo (TSE) sequences. We acquired navigator-triggered SPACE and conventional 3D-TSE MRCP images using the same parameters where possible for 30 patients and compared the image acquisition time, contrast, and contrast-to-noise ratio (CNR) of the common bile duct (CBD). Two radiologists performed qualitative analyses using a 4-point scale. Image acquisition time was 31% shorter with the SPACE than the conventional TSE sequence (248.9 ± 73.0 sec vs. 360.5 ± 99.9 sec, P TSE (39.4 ± 14.7 vs. 33.5 ± 14.2, P TSE sequence; there was a significant difference in motion artifacts and the depiction of the CBD and the left hepatic and main pancreatic duct (P TSE. Copyright © 2013 Wiley Periodicals, Inc.

  3. Efficient Coding of Shape and Transparency for Video Objects

    DEFF Research Database (Denmark)

    Aghito, Shankar Manuel; Forchhammer, Søren

    2007-01-01

    A novel scheme for coding gray-level alpha planes in object-based video is presented. Gray-level alpha planes convey the shape and the transparency information, which are required for smooth composition of video objects. The algorithm proposed is based on the segmentation of the alpha plane...... shape layer is processed by a novel video shape coder. In intra mode, the DSLSC binary image coder presented in is used. This is extended here with an intermode utilizing temporal redundancies in shape image sequences. Then the opaque layer is compressed by a newly designed scheme which models...

  4. EEG Sequence Imaging: A Markov Prior for the Variational Garrote

    DEFF Research Database (Denmark)

    Hansen, Sofie Therese; Hansen, Lars Kai

    2013-01-01

    We propose the following generalization of the Variational Garrote for sequential EEG imaging: A Markov prior to promote sparse, but temporally smooth source dynamics. We derive a set of modied Variational Garrote updates and analyze the role of the prior's hyperparameters. An experimental...

  5. Outdoor Illumination Estimation in Image Sequences for Augmented Reality

    DEFF Research Database (Denmark)

    Madsen, Claus B.; Lal, Brajesh Behari

    2011-01-01

    the detected shadows is used to estimate the radiance of the sun. The technique does not require special purpose objects in the scene, nor does it require High Dynamic Range imagery. Results are demonstrated by rendering augmented objects into real images with shading and shadows which are consistent...

  6. Gender Recognition from Human-Body Images Using Visible-Light and Thermal Camera Videos Based on a Convolutional Neural Network for Image Feature Extraction

    Science.gov (United States)

    Nguyen, Dat Tien; Kim, Ki Wan; Hong, Hyung Gil; Koo, Ja Hyung; Kim, Min Cheol; Park, Kang Ryoung

    2017-01-01

    Extracting powerful image features plays an important role in computer vision systems. Many methods have previously been proposed to extract image features for various computer vision applications, such as the scale-invariant feature transform (SIFT), speed-up robust feature (SURF), local binary patterns (LBP), histogram of oriented gradients (HOG), and weighted HOG. Recently, the convolutional neural network (CNN) method for image feature extraction and classification in computer vision has been used in various applications. In this research, we propose a new gender recognition method for recognizing males and females in observation scenes of surveillance systems based on feature extraction from visible-light and thermal camera videos through CNN. Experimental results confirm the superiority of our proposed method over state-of-the-art recognition methods for the gender recognition problem using human body images. PMID:28335510

  7. Gender Recognition from Human-Body Images Using Visible-Light and Thermal Camera Videos Based on a Convolutional Neural Network for Image Feature Extraction

    Directory of Open Access Journals (Sweden)

    Dat Tien Nguyen

    2017-03-01

    Full Text Available Extracting powerful image features plays an important role in computer vision systems. Many methods have previously been proposed to extract image features for various computer vision applications, such as the scale-invariant feature transform (SIFT, speed-up robust feature (SURF, local binary patterns (LBP, histogram of oriented gradients (HOG, and weighted HOG. Recently, the convolutional neural network (CNN method for image feature extraction and classification in computer vision has been used in various applications. In this research, we propose a new gender recognition method for recognizing males and females in observation scenes of surveillance systems based on feature extraction from visible-light and thermal camera videos through CNN. Experimental results confirm the superiority of our proposed method over state-of-the-art recognition methods for the gender recognition problem using human body images.

  8. Gender Recognition from Human-Body Images Using Visible-Light and Thermal Camera Videos Based on a Convolutional Neural Network for Image Feature Extraction.

    Science.gov (United States)

    Nguyen, Dat Tien; Kim, Ki Wan; Hong, Hyung Gil; Koo, Ja Hyung; Kim, Min Cheol; Park, Kang Ryoung

    2017-03-20

    Extracting powerful image features plays an important role in computer vision systems. Many methods have previously been proposed to extract image features for various computer vision applications, such as the scale-invariant feature transform (SIFT), speed-up robust feature (SURF), local binary patterns (LBP), histogram of oriented gradients (HOG), and weighted HOG. Recently, the convolutional neural network (CNN) method for image feature extraction and classification in computer vision has been used in various applications. In this research, we propose a new gender recognition method for recognizing males and females in observation scenes of surveillance systems based on feature extraction from visible-light and thermal camera videos through CNN. Experimental results confirm the superiority of our proposed method over state-of-the-art recognition methods for the gender recognition problem using human body images.

  9. Rapid Measurements of Intensities for Safety Assessment of Advanced Imaging Sequences

    DEFF Research Database (Denmark)

    Jensen, Jørgen Arendt; Rasmussen, Morten Fischer; Stuart, Matthias Bo

    2014-01-01

    FDA requires that intensity and safety parameters are measured for all imaging schemes for clinical imaging. This is often cumbersome, since the scan sequence has to broken apart, measurements conducted for the individually emitted beams, and the nal intensity levels calculated by combining the i...

  10. Retrieval of Sentence Sequences for an Image Stream via Coherence Recurrent Convolutional Networks.

    Science.gov (United States)

    Park, Cesc; Kim, Youngjin; Kim, Gunhee

    2017-05-02

    We propose an approach for retrieving a sequence of natural sentences for an image stream. Since general users often take a series of pictures on their experiences, much online visual information exists in the form of image streams, for which it would better take into consideration of the whole image stream to produce natural language descriptions. While almost all previous studies have dealt with the relation between a single image and a single natural sentence, our work extends both input and output dimension to a sequence of images and a sequence of sentences. For retrieving a coherent flow of multiple sentences for a photo stream, we propose a multimodal neural architecture called coherence recurrent convolutional network (CRCN), which consists of convolutional neural networks, bidirectional long short-term memory (LSTM) networks, and an entity-based local coherence model. Our approach directly learns from vast user-generated resource of blog posts as text-image parallel training data. We collect more than 22K unique blog posts with 170K associated images for the travel topics of NYC, Disneyland, Australia, and Hawaii. We demonstrate that our approach outperforms other state-of-the-art image captioning methods for text sequence generation, using both quantitative measures and user studies via Amazon Mechanical Turk.

  11. Lossless image data sequence compression using optimal context quantization

    DEFF Research Database (Denmark)

    Forchhammer, Søren; WU, Xiaolin; Andersen, Jakob Dahl

    2001-01-01

    Context based entropy coding often faces the conflict of a desire for large templates and the problem of context dilution. We consider the problem of finding the quantizer Q that quantizes the K-dimensional causal context Ci=(X(i-t1), X(i-t2), …, X(i-tK)) of a source symbol Xi into one of M...... and context quantization for coding the binary decisions is presented and applied to digital maps and α-plane sequences. The optimal context quantization is also used to evaluate existing heuristic context quantizations....

  12. Real time three-dimensional space video rate sensors for millimeter waves imaging based very inexpensive plasma LED lamps

    Science.gov (United States)

    Levanon, Assaf; Yitzhaky, Yitzhak; Kopeika, Natan S.; Rozban, Daniel; Abramovich, Amir

    2014-10-01

    In recent years, much effort has been invested to develop inexpensive but sensitive Millimeter Wave (MMW) detectors that can be used in focal plane arrays (FPAs), in order to implement real time MMW imaging. Real time MMW imaging systems are required for many varied applications in many fields as homeland security, medicine, communications, military products and space technology. It is mainly because this radiation has high penetration and good navigability through dust storm, fog, heavy rain, dielectric materials, biological tissue, and diverse materials. Moreover, the atmospheric attenuation in this range of the spectrum is relatively low and the scattering is also low compared to NIR and VIS. The lack of inexpensive room temperature imaging systems makes it difficult to provide a suitable MMW system for many of the above applications. In last few years we advanced in research and development of sensors using very inexpensive (30-50 cents) Glow Discharge Detector (GDD) plasma indicator lamps as MMW detectors. This paper presents three kinds of GDD sensor based lamp Focal Plane Arrays (FPA). Those three kinds of cameras are different in the number of detectors, scanning operation, and detection method. The 1st and 2nd generations are 8 × 8 pixel array and an 18 × 2 mono-rail scanner array respectively, both of them for direct detection and limited to fixed imaging. The last designed sensor is a multiplexing frame rate of 16x16 GDD FPA. It permits real time video rate imaging of 30 frames/ sec and comprehensive 3D MMW imaging. The principle of detection in this sensor is a frequency modulated continuous wave (FMCW) system while each of the 16 GDD pixel lines is sampled simultaneously. Direct detection is also possible and can be done with a friendly user interface. This FPA sensor is built over 256 commercial GDD lamps with 3 mm diameter International Light, Inc., Peabody, MA model 527 Ne indicator lamps as pixel detectors. All three sensors are fully supported

  13. Towards an automated analysis of video-microscopy images of fungal morphogenesis

    Directory of Open Access Journals (Sweden)

    Diéguez-Uribeondo, Javier

    2005-06-01

    Full Text Available Fungal morphogenesis is an exciting field of cell biology and several mathematical models have been developed to describe it. These models require experimental evidences to be corroborated and, therefore, there is a continuous search for new microscopy and image analysis techniques. In this work, we have used a Canny-edge-detector based technique to automate the generation of hyphal profiles and calculation of morphogenetic parameters such as diameter, elongation rates and hyphoid fitness. The results show that the data obtained with this technique are similar to published data generated with manualbased tracing techniques and that have been carried out on the same species or genus. Thus, we show that application of edge detector-based technique to hyphal growth represents an efficient and accurate method to study hyphal morphogenesis. This represents the first step towards an automated analysis of videomicroscopy images of fungal morphogenesis.La morfogénesis de los hongos es un área de estudio de gran relevancia en la biología celular y en la que se han desarrollado varios modelos matemáticos. Los modelos matemáticos de procesos biológicos precisan de pruebas experimentales que apoyen y corroboren las predicciones teóricas y, por este motivo, existe una búsqueda continua de nuevas técnicas de microscopía y análisis de imágenes para su aplicación en el estudio del crecimiento celular. En este trabajo hemos utilizado una técnica basada en un detector de contornos llamado “Canny-edge-detectorâ€� con el objetivo de automatizar la generación de perfiles de hifas y el cálculo de parámetros morfogenéticos, tales como: el diámetro, la velocidad de elongación y el ajuste con el perfil hifoide, es decir, el perfil teórico de las hifas de los hongos. Los resultados obtenidos son similares a los datos publicados a partir de técnicas manuales de trazado de contornos, generados en la misma especie y género. De esta manera

  14. A framework for the recognition of high-level surgical tasks from video images for cataract surgeries

    Science.gov (United States)

    Lalys, Florent; Riffaud, Laurent; Bouget, David; Jannin, Pierre

    2012-01-01

    The need for a better integration of the new generation of Computer-Assisted-Surgical (CAS) systems has been recently emphasized. One necessity to achieve this objective is to retrieve data from the Operating Room (OR) with different sensors, then to derive models from these data. Recently, the use of videos from cameras in the OR has demonstrated its efficiency. In this paper, we propose a framework to assist in the development of systems for the automatic recognition of high level surgical tasks using microscope videos analysis. We validated its use on cataract procedures. The idea is to combine state-of-the-art computer vision techniques with time series analysis. The first step of the framework consisted in the definition of several visual cues for extracting semantic information, therefore characterizing each frame of the video. Five different pieces of image-based classifiers were therefore implemented. A step of pupil segmentation was also applied for dedicated visual cue detection. Time series classification algorithms were then applied to model time-varying data. Dynamic Time Warping (DTW) and Hidden Markov Models (HMM) were tested. This association combined the advantages of all methods for better understanding of the problem. The framework was finally validated through various studies. Six binary visual cues were chosen along with 12 phases to detect, obtaining accuracies of 94%. PMID:22203700

  15. Optimal JPWL Forward Error Correction Rate Allocation for Robust JPEG 2000 Images and Video Streaming over Mobile Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Benoit Macq

    2008-07-01

    Full Text Available Based on the analysis of real mobile ad hoc network (MANET traces, we derive in this paper an optimal wireless JPEG 2000 compliant forward error correction (FEC rate allocation scheme for a robust streaming of images and videos over MANET. The packet-based proposed scheme has a low complexity and is compliant to JPWL, the 11th part of the JPEG 2000 standard. The effectiveness of the proposed method is evaluated using a wireless Motion JPEG 2000 client/server application; and the ability of the optimal scheme to guarantee quality of service (QoS to wireless clients is demonstrated.

  16. Video super-resolution using simultaneous motion and intensity calculations

    DEFF Research Database (Denmark)

    Keller, Sune Høgild; Lauze, Francois Bernard; Nielsen, Mads

    2011-01-01

    In this paper we propose an energy based algorithm for motion compensated video super-resolution (VSR) targeted on upscaling of standard definition (SD) video to high definition (HD) video. Since the motion (flow field) of the image sequence is generally unknown, we introduce a formulation...... for super-resolved sequences. Computing super-resolved flows has to our knowledge not been done before. Most advanced super-resolution (SR) methods found in literature cannot be applied to general video with arbitrary scene content and/or arbitrary optical flows, as it is possible with our simultaneous VSR...... method. Series of experiments show that our method outperforms other VSR methods when dealing with general video input and that it continues to provide good results even for large scaling factors, up to 8×8....

  17. Preparation of 2D sequences of corneal images for 3D model building.

    Science.gov (United States)

    Elbita, Abdulhakim; Qahwaji, Rami; Ipson, Stanley; Sharif, Mhd Saeed; Ghanchi, Faruque

    2014-04-01

    A confocal microscope provides a sequence of images, at incremental depths, of the various corneal layers and structures. From these, medical practioners can extract clinical information on the state of health of the patient's cornea. In this work we are addressing problems associated with capturing and processing these images including blurring, non-uniform illumination and noise, as well as the displacement of images laterally and in the anterior-posterior direction caused by subject movement. The latter may cause some of the captured images to be out of sequence in terms of depth. In this paper we introduce automated algorithms for classification, reordering, registration and segmentation to solve these problems. The successful implementation of these algorithms could open the door for another interesting development, which is the 3D modelling of these sequences. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  18. Social Evaluations of Stereotypic Images in Video Games: Unfair, Legitimate, or "Just Entertainment"?

    Science.gov (United States)

    Brenick, Alaina; Henning, Alexandra; Killen, Melanie; O'Connor, Alexander; Collins, Michael

    2007-01-01

    The aim of this study is to assess late adolescents' evaluations of and reasoning about gender stereotypes in video games. Female (n = 46) and male (n = 41) students, predominantly European American, with a mean age 19 years, are interviewed about their knowledge of game usage, awareness and evaluation of stereotypes, beliefs about the influences…

  19. The Moving Image in Education Research: Reassembling the Body in Classroom Video Data

    Science.gov (United States)

    de Freitas, Elizabeth

    2016-01-01

    While audio recordings and observation might have dominated past decades of classroom research, video data is now the dominant form of data in the field. Ubiquitous videography is standard practice today in archiving the body of both the teacher and the student, and vast amounts of classroom and experiment clips are stored in online archives. Yet…

  20. Video monitoring in the Gadria debris flow catchment: preliminary results of large scale particle image velocimetry (LSPIV)

    Science.gov (United States)

    Theule, Joshua; Crema, Stefano; Comiti, Francesco; Cavalli, Marco; Marchi, Lorenzo

    2015-04-01

    Large scale particle image velocimetry (LSPIV) is a technique mostly used in rivers to measure two dimensional velocities from high resolution images at high frame rates. This technique still needs to be thoroughly explored in the field of debris flow studies. The Gadria debris flow monitoring catchment in Val Venosta (Italian Alps) has been equipped with four MOBOTIX M12 video cameras. Two cameras are located in a sediment trap located close to the alluvial fan apex, one looking upstream and the other looking down and more perpendicular to the flow. The third camera is in the next reach upstream from the sediment trap at a closer proximity to the flow. These three cameras are connected to a field shelter equipped with power supply and a server collecting all the monitoring data. The fourth camera is located in an active gully, the camera is activated by a rain gauge when there is one minute of rainfall. Before LSPIV can be used, the highly distorted images need to be corrected and accurate reference points need to be made. We decided to use IMGRAFT (an opensource image georectification toolbox) which can correct distorted images using reference points and camera location, and then finally rectifies the batch of images onto a DEM grid (or the DEM grid onto the image coordinates). With the orthorectified images, we used the freeware Fudaa-LSPIV (developed by EDF, IRSTEA, and DeltaCAD Company) to generate the LSPIV calculations of the flow events. Calculated velocities can easily be checked manually because of the already orthorectified images. During the monitoring program (since 2011) we recorded three debris flow events at the sediment trap area (each with very different surge dynamics). The camera in the gully was in operation in 2014 which managed to record granular flows and rockfalls, which particle tracking may be more appropriate for velocity measurements. The four cameras allows us to explore the limitations of camera distance, angle, frame rate, and image

  1. Video Salient Object Detection via Fully Convolutional Networks

    Science.gov (United States)

    Wang, Wenguan; Shen, Jianbing; Shao, Ling

    2018-01-01

    This paper proposes a deep learning model to efficiently detect salient regions in videos. It addresses two important issues: (1) deep video saliency model training with the absence of sufficiently large and pixel-wise annotated video data, and (2) fast video saliency training and detection. The proposed deep video saliency network consists of two modules, for capturing the spatial and temporal saliency information, respectively. The dynamic saliency model, explicitly incorporating saliency estimates from the static saliency model, directly produces spatiotemporal saliency inference without time-consuming optical flow computation. We further propose a novel data augmentation technique that simulates video training data from existing annotated image datasets, which enables our network to learn diverse saliency information and prevents overfitting with the limited number of training videos. Leveraging our synthetic video data (150K video sequences) and real videos, our deep video saliency model successfully learns both spatial and temporal saliency cues, thus producing accurate spatiotemporal saliency estimate. We advance the state-of-the-art on the DAVIS dataset (MAE of .06) and the FBMS dataset (MAE of .07), and do so with much improved speed (2fps with all steps).

  2. Top-Down and Bottom-Up Cues Based Moving Object Detection for Varied Background Video Sequences

    Directory of Open Access Journals (Sweden)

    Chirag I. Patel

    2014-01-01

    there is no need for background formulation and updates as it is background independent. Many bottom-up approaches and one combination of bottom-up and top-down approaches are proposed in the present paper. The proposed approaches seem more efficient due to inessential requirement of learning background model and due to being independent of previous video frames. Results indicate that the proposed approach works even against slight movements in the background and in various outdoor conditions.

  3. An efficient HW and SW design of H.264 video compression, storage and playback on FPGA devices for handheld thermal imaging systems

    Science.gov (United States)

    Gunay, Omer; Ozsarac, Ismail; Kamisli, Fatih

    2017-05-01

    Video recording is an essential property of new generation military imaging systems. Playback of the stored video on the same device is also desirable as it provides several operational benefits to end users. Two very important constraints for many military imaging systems, especially for hand-held devices and thermal weapon sights, are power consumption and size. To meet these constraints, it is essential to perform most of the processing applied to the video signal, such as preprocessing, compression, storing, decoding, playback and other system functions on a single programmable chip, such as FPGA, DSP, GPU or ASIC. In this work, H.264/AVC (Advanced Video Coding) compatible video compression, storage, decoding and playback blocks are efficiently designed and implemented on FPGA platforms using FPGA fabric and Altera NIOS II soft processor. Many subblocks that are used in video encoding are also used during video decoding in order to save FPGA resources and power. Computationally complex blocks are designed using FPGA fabric, while blocks such as SD card write/read, H.264 syntax decoding and CAVLC decoding are done using NIOS processor to benefit from software flexibility. In addition, to keep power consumption low, the system was designed to require limited external memory access. The design was tested using 640x480 25 fps thermal camera on CYCLONE V FPGA, which is the ALTERA's lowest power FPGA family, and consumes lower than 40% of CYCLONE V 5CEFA7 FPGA resources on average.

  4. Reconstructing Interlaced High-Dynamic-Range Video Using Joint Learning.

    Science.gov (United States)

    Choi, Inchang; Baek, Seung-Hwan; Kim, Min H

    2017-11-01

    For extending the dynamic range of video, it is a common practice to capture multiple frames sequentially with different exposures and combine them to extend the dynamic range of each video frame. However, this approach results in typical ghosting artifacts due to fast and complex motion in nature. As an alternative, video imaging with interlaced exposures has been introduced to extend the dynamic range. However, the interlaced approach has been hindered by jaggy artifacts and sensor noise, leading to concerns over image quality. In this paper, we propose a data-driven approach for jointly solving two specific problems of deinterlacing and denoising that arise in interlaced video imaging with different exposures. First, we solve the deinterlacing problem using joint dictionary learning via sparse coding. Since partial information of detail in differently exposed rows is often available via interlacing, we make use of the information to reconstruct details of the extended dynamic range from the interlaced video input. Second, we jointly solve the denoising problem by tailoring sparse coding to better handle additive noise in low-/high-exposure rows, and also adopt multiscale homography flow to temporal sequences for denoising. We anticipate that the proposed method will allow for concurrent capture of higher dynamic range video frames without suffering from ghosting artifacts. We demonstrate the advantages of our interlaced video imaging compared with the state-of-the-art high-dynamic-range video methods.

  5. Capturing and displaying microscopic images used in medical diagnostics and forensic science using 4K video resolution - an application in higher education.

    Science.gov (United States)

    Maier, Hans; de Heer, Gert; Ortac, Ajda; Kuijten, Jan

    2015-11-01

    To analyze, interpret and evaluate microscopic images, used in medical diagnostics and forensic science, video images for educational purposes were made with a very high resolution of 4096 × 2160 pixels (4K), which is four times as many pixels as High-Definition Video (1920 × 1080 pixels). The unprecedented high resolution makes it possible to see details that remain invisible to any other video format. The images of the specimens (blood cells, tissue sections, hair, fibre, etc.) are recorded using a 4K video camera which is attached to a light microscope. After processing, this resulted in very sharp and highly detailed images. This material was then used in education for classroom discussion. Spoken explanation by experts in the field of medical diagnostics and forensic science was also added to the high-resolution video images to make it suitable for self-study. © 2015 The Authors. Journal of Microscopy published by John Wiley & Sons Ltd on behalf of Royal Microscopical Society.

  6. Automatic delamination defect detection in radiographic sequence of rocket boosters; Determination automatique de defauts de delaminage dans des sequences d'images radiographiques de propulseurs de fusee

    Energy Technology Data Exchange (ETDEWEB)

    Rebuffel, V.; Pires, S. [CEA Grenoble, Lab. d' Electronique et de Technologie de l' Informatique (LETI/DSIS/SSBS), 38 (France); Caplier, A. [Institut National Polytechnique, 38 - Grenoble (France); Lamarque, P. [SNPE, 75 - Paris (France)

    2003-07-01

    instantaneous confidence image (the required parameter is automatically tuned by local statistic tests). The confidence images are then cumulated over time to get indicators values of the probability of a pixel to belong to a defect. A hysteresis function allows to enhance the defects by adding a neighbourhood validation. Finally the defects are extracted, and characterized in terms of shape and other parameters in the sequence of radiographs. These parameters are finally transformed in the geometry of the object. Thus the method combines spatial and temporal aspects in both detection and characterization. Several experimental tests are presented, on true radiographs of boosters, where delamination small to 1 mm have been detected, and on other cylindrical objects, such as nuclear waste containers. Because defects are fortunately uncommon in these objects, simulations are also used to establish the limits of the algorithm. Both examples would be shown using video animation at the conference. (authors)

  7. Synthesis of Speaker Facial Movement to Match Selected Speech Sequences

    Science.gov (United States)

    Scott, K. C.; Kagels, D. S.; Watson, S. H.; Rom, H.; Wright, J. R.; Lee, M.; Hussey, K. J.

    1994-01-01

    A system is described which allows for the synthesis of a video sequence of a realistic-appearing talking human head. A phonic based approach is used to describe facial motion; image processing rather than physical modeling techniques are used to create video frames.

  8. Comparison of 3 T and 7 T MRI clinical sequences for ankle imaging

    Energy Technology Data Exchange (ETDEWEB)

    Juras, Vladimir, E-mail: vladimir.juras@meduniwien.ac.at [Medical University of Vienna, Department of Radiology, Vienna General Hospital, Waeringer Guertel 18-20, A-1090 Vienna (Austria); Slovak Academy of Sciences, Institute of Measurement Science, Dubravska cesta 9, 84104 Bratislava (Slovakia); Welsch, Goetz, E-mail: welsch@bwh.harvard.edu [Medical University of Vienna, Department of Radiology, Vienna General Hospital, Waeringer Guertel 18-20, A-1090 Vienna (Austria); Baer, Peter, E-mail: baerpeter@siemens.com [Siemens Healthcare, Richard-Strauss-Strasse 76, D81679 Munich (Germany); Kronnerwetter, Claudia, E-mail: claudia.kronnerwetter@meduniwien.ac.at [Medical University of Vienna, Department of Radiology, Vienna General Hospital, Waeringer Guertel 18-20, A-1090 Vienna (Austria); Fujita, Hiroyuki, E-mail: hiroyuki.fujita@qualedyn.com [Quality Electrodynamics, LCC, 777 Beta Dr, Cleveland, OH 44143-2336 (United States); Trattnig, Siegfried, E-mail: siegfried.trattnig@meduniwien.ac.at [Medical University of Vienna, Department of Radiology, Vienna General Hospital, Waeringer Guertel 18-20, A-1090 Vienna (Austria)

    2012-08-15

    The purpose of this study was to compare 3 T and 7 T signal-to-noise and contrast-to noise ratios of clinical sequences for imaging of the ankles with optimized sequences and dedicated coils. Ten healthy volunteers were examined consecutively on both systems with three clinical sequences: (1) 3D gradient-echo, T{sub 1}-weighted; (2) 2D fast spin-echo, PD-weighted; and (3) 2D spin-echo, T{sub 1}-weighted. SNR was calculated for six regions: cartilage; bone; muscle; synovial fluid; Achilles tendon; and Kager's fat-pad. CNR was obtained for cartilage/bone, cartilage/fluid, cartilage/muscle, and muscle/fat-pad, and compared by a one-way ANOVA test for repeated measures. Mean SNR significantly increased at 7 T compared to 3 T for 3D GRE, and 2D TSE was 60.9% and 86.7%, respectively. In contrast, an average SNR decrease of almost 25% was observed in the 2D SE sequence. A CNR increase was observed in 2D TSE images, and in most 3D GRE images. There was a substantial benefit from ultra high-field MR imaging of ankles with routine clinical sequences at 7 T compared to 3 T. Higher SNR and CNR at ultra-high field MR scanners may be useful in clinical practice for ankle imaging. However, carefully optimized protocols and dedicated extremity coils are necessary to obtain optimal results.

  9. The advantages of using photographs and video images in telephone consultations with a specialist in paediatric surgery

    Directory of Open Access Journals (Sweden)

    Ibrahim Akkoyun

    2012-01-01

    Full Text Available Background: The purpose of this study was to evaluate the advantages of a telephone consultation with a specialist in paediatric surgery after taking photographs and video images by a general practitioner for the diagnosis of some diseases. Materials and Methods: This was a prospective study of the reliability of paediatric surgery online consultation among specialists and general practitioners. Results: Of 26 general practitioners included in the study, 12 were working in the city and 14 were working in districts outside the city. A total of 41 pictures and 3 videos of 38 patients were sent and evaluated together with the medical history and clinical findings. These patients were diagnosed with umbilical granuloma (n = 6, physiological/pathological phimosis (n = 6, balanitis (n = 6, hydrocele (n = 6, umbilical hernia (n = 4, smegma cyst (n = 2, reductable inguinal hernia (n = 1, incarcerated inguinal hernia (n = 1, paraphimosis (n = 1, burried penis (n = 1, hypospadias (n = 1, epigastric hernia (n = 1, vulva synechia (n = 1, and rectal prolapse (n = 1. Twelve patients were asked to be referred urgently, but it was suggested that only two of these patients, who had paraphimosis and incarcerated inguinal hernia be referred in emergency conditions. It was decided that there was no need for the other ten patients to be referred to a specialist at night or at the weekend. All diagnoses were confirmed to be true, when all patients underwent examination in the pediatric surgery clinic in elective conditions. Conclusion: Evaluation of photographs and video images of a lesion together with medical history and clinical findings via a telephone consultation between a paediatric surgery specialist and a general practitioner provides a definitive diagnosis and prevents patients from being referred unnecessarily.

  10. Shadow Areas Robust Matching Among Image Sequence in Planetary Landing

    Science.gov (United States)

    Ruoyan, Wei; Xiaogang, Ruan; Naigong, Yu; Xiaoqing, Zhu; Jia, Lin

    2017-01-01

    In this paper, an approach for robust matching shadow areas in autonomous visual navigation and planetary landing is proposed. The approach begins with detecting shadow areas, which are extracted by Maximally Stable Extremal Regions (MSER). Then, an affine normalization algorithm is applied to normalize the areas. Thirdly, a descriptor called Multiple Angles-SIFT (MA-SIFT) that coming from SIFT is proposed, the descriptor can extract more features of an area. Finally, for eliminating the influence of outliers, a method of improved RANSAC based on Skinner Operation Condition is proposed to extract inliers. At last, series of experiments are conducted to test the performance of the approach this paper proposed, the results show that the approach can maintain the matching accuracy at a high level even the differences among the images are obvious with no attitude measurements supplied.

  11. Compression of Video-Otoscope Images for Tele-Otology: A Pilot Study

    Science.gov (United States)

    2001-10-25

    algorithm used in image compression is the one developed by the Joint Picture Expert Group (JPEG), which has been deployed in almost all imaging ...recognised the image , nor go back to view the previous images . This was designed to minimise the affect of memory . After the assessments were tabulated...also have contributed such as the memory effect, or the experience of the assessor. V. CONCLUSION 1. Images can probably be compressed to about

  12. Relevance of 3D magnetic resonance imaging sequences in diagnosing basal subarachnoid neurocysticercosis.

    Science.gov (United States)

    Carrillo Mezo, Roger; Lara García, Javier; Arroyo, Mariana; Fleury, Agnès

    2015-12-01

    Imagenological diagnosis of subarachnoid neurocysticercosis is usually difficult when classical magnetic resonance imaging (MRI) sequences are used. The purpose of this study was to evaluate the advantages of 3D MRI sequences (Fast Imaging Employing Steady-state Acquisition (FIESTA) and Spoiled Gradient Recalled Echo (SPGR)) with respect to classical sequences (Fluid Attenuation Inversion Recovery (FLAIR) and T1) in visualizing Taenia solium cyst in these locations. Forty-seven T. solium cysts located in the basal cisterns of the subarachnoid space were diagnosed in eighteen Mexican patients. A pre-treatment MRI was performed on all patients, and all four sequences (FIESTA, FLAIR, T1 SPGR, and T2) were evaluated independently by two neuroradiologists. The sensitivity of each sequence to detect the parasite membrane and scolex was evaluated, along with its capacity to detect differences in signal intensity between cerebrospinal fluid (CSF) and cysts. FIESTA sequences allowed the visualization of cyst membrane in 87.2% of the parasites evaluated, FLAIR in 38.3%, SPGR in 23.4%, and T2 in 17.0%. The superiority of FIESTA sequences over the other three imaging methods was statistically significant (P0.05). Differences in signal intensity between CSF and parasite cysts were significant in FIESTA (P<0.0001), SPGR (P<0.0001), and FLAIR (P=0.005) sequences. For the first time, the usefulness of 3D MRI sequences to diagnose T. solium cysts located in the basal cisterns of the subarachnoid space was demonstrated. The routine use of these sequences could favor an earlier diagnosis and greatly improve the prognosis of patients affected by this severe form of the disease. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. Comparison of Computer Vision and Photogrammetric Approaches for Epipolar Resampling of Image Sequence.

    Science.gov (United States)

    Kim, Jae-In; Kim, Taejung

    2016-03-22

    Epipolar resampling is the procedure of eliminating vertical disparity between stereo images. Due to its importance, many methods have been developed in the computer vision and photogrammetry field. However, we argue that epipolar resampling of image sequences, instead of a single pair, has not been studied thoroughly. In this paper, we compare epipolar resampling methods developed in both fields for handling image sequences. Firstly we briefly review the uncalibrated and calibrated epipolar resampling methods developed in computer vision and photogrammetric epipolar resampling methods. While it is well known that epipolar resampling methods developed in computer vision and in photogrammetry are mathematically identical, we also point out differences in parameter estimation between them. Secondly, we tested representative resampling methods in both fields and performed an analysis. We showed that for epipolar resampling of a single image pair all uncalibrated and photogrammetric methods tested could be used. More importantly, we also showed that, for image sequences, all methods tested, except the photogrammetric Bayesian method, showed significant variations in epipolar resampling performance. Our results indicate that the Bayesian method is favorable for epipolar resampling of image sequences.

  14. Comparison of Computer Vision and Photogrammetric Approaches for Epipolar Resampling of Image Sequence

    Directory of Open Access Journals (Sweden)

    Jae-In Kim

    2016-03-01

    Full Text Available Epipolar resampling is the procedure of eliminating vertical disparity between stereo images. Due to its importance, many methods have been developed in the computer vision and photogrammetry field. However, we argue that epipolar resampling of image sequences, instead of a single pair, has not been studied thoroughly. In this paper, we compare epipolar resampling methods developed in both fields for handling image sequences. Firstly we briefly review the uncalibrated and calibrated epipolar resampling methods developed in computer vision and photogrammetric epipolar resampling methods. While it is well known that epipolar resampling methods developed in computer vision and in photogrammetry are mathematically identical, we also point out differences in parameter estimation between them. Secondly, we tested representative resampling methods in both fields and performed an analysis. We showed that for epipolar resampling of a single image pair all uncalibrated and photogrammetric methods tested could be used. More importantly, we also showed that, for image sequences, all methods tested, except the photogrammetric Bayesian method, showed significant variations in epipolar resampling performance. Our results indicate that the Bayesian method is favorable for epipolar resampling of image sequences.

  15. Understanding 3D TSE Sequences: Advantages, Disadvantages, and Application in MSK Imaging.

    Science.gov (United States)

    Glaser, Christian; D'Anastasi, Melvin; Theisen, Daniel; Notohamiprodjo, Mike; Horger, Wilhelm; Paul, Dominik; Horng, Annie

    2015-09-01

    Three-dimensional (3D) turbo-spin echo (TSE) sequences have outgrown the stage of mere sequence optimization and by now are clinically applicable. Image blurring and acquisition times have been reduced, and contrast for T1-, T2-, and moderately T2-weighted (or intermediate-weighted) fat-suppressed variants has been optimized. Data on sound-to-noise ratio efficiency and contrast are available for moderately T2-weighted fat-saturated sequence protocols. The 3-T MRI scanners help to better exploit isotropic spatial resolution and multiplanar reformatting. Imaging times range from 5 to 10 minutes, and they are shorter than the cumulative acquisition times of three separate orthogonal two-dimensional (2D) sequences. Recent suggestions go beyond secondary reformations by using online 3D rendering for image evaluation. Comparative clinical studies indicate that the diagnostic performance of 3D TSE for imaging of internal derangements of joints is at least comparable with conventional 2D TSE with potential advantages of 3D TSE for small highly curved structures. But such studies, especially those with direct arthroscopic correlation, are still sparse. Whether 3D TSE will succeed in entering clinical routine imaging on a broader scale will depend on further published clinical evidence, on further reduction of imaging time, and on improvement of its integration into daily practice. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  16. Social Evaluations of Stereotypic Images in Video Games: Unfair, Legitimate, or "Just Entertainment"?

    Science.gov (United States)

    Brenick, Alaina; Henning, Alexandra; Killen, Melanie; O'Connor, Alexander; Collins, Michael

    2007-06-01

    The aim of this study was to assess adolescents' evaluations of, and reasoning about, gender stereotypes in video games. Female (N = 46) and male (N = 41), predominantly European-American, mean age = 19 years, were interviewed about their knowledge of game usage, awareness and evaluation of stereotypes, beliefs about the influences of games on the players, and authority jurisdiction over 3 different types of games: games with negative male stereotypes, and games with negative female stereotypes, and gender-neutral games. Gender differences were found for how participants evaluated these games. Males were more likely than females to find stereotypes acceptable. Results are discussed in terms of social reasoning, video game playing, and gender differences.

  17. Social Evaluations of Stereotypic Images in Video Games: Unfair, Legitimate, or “Just Entertainment”?

    Science.gov (United States)

    Brenick, Alaina; Henning, Alexandra; Killen, Melanie; O'Connor, Alexander; Collins, Michael

    2015-01-01

    The aim of this study was to assess adolescents' evaluations of, and reasoning about, gender stereotypes in video games. Female (N = 46) and male (N = 41), predominantly European-American, mean age = 19 years, were interviewed about their knowledge of game usage, awareness and evaluation of stereotypes, beliefs about the influences of games on the players, and authority jurisdiction over 3 different types of games: games with negative male stereotypes, and games with negative female stereotypes, and gender-neutral games. Gender differences were found for how participants evaluated these games. Males were more likely than females to find stereotypes acceptable. Results are discussed in terms of social reasoning, video game playing, and gender differences. PMID:25722501

  18. Social Evaluations of Stereotypic Images in Video Games: Unfair, Legitimate, or “Just Entertainment”?

    OpenAIRE

    Brenick, Alaina; Henning, Alexandra; Killen, Melanie; O'Connor, Alexander; Collins, Michael

    2007-01-01

    The aim of this study was to assess adolescents' evaluations of, and reasoning about, gender stereotypes in video games. Female (N = 46) and male (N = 41), predominantly European-American, mean age = 19 years, were interviewed about their knowledge of game usage, awareness and evaluation of stereotypes, beliefs about the influences of games on the players, and authority jurisdiction over 3 different types of games: games with negative male stereotypes, and games with negative female stereotyp...

  19. Photometric-Photogrammetric Analysis of Video Images of a Venting of Water from Space Shuttle Discovery

    Science.gov (United States)

    1990-06-15

    simulations), which are accompanied by a much less-dense cloud of subrnicron ice droplets produced when the evaporated/sublimed water gas overexpands and...Focus, pan and tilt angles, and angular field are controlled from the crew cabin with the aid of a monochrome video monitor. (Some of these cameras...ice particles when this gas has become overexpanded . 2) The angular spreads of the two types of particle are the same within experimental uncertainty

  20. Moving Shadow Detection in Video Using Cepstrum Regular Paper

    OpenAIRE

    Cogun, Fuat; Cetin, Ahmet Enis

    2013-01-01

    Moving shadows constitute problems in various applications such as image segmentation and object tracking. The main cause of these problems is the misclassification of the shadow pixels as target pixels. Therefore, the use of an accurate and reliable shadow detection method is essential to realize intelligent video processing applications. In this paper, a cepstrum‐based method for moving shadow detection is presented. The proposed method is tested on outdoor and indoor video sequences using ...

  1. Microscopic imaging of slow flow and diffusion: a pulsed field gradient stimulated echo sequence combined with turbo spin echo imaging

    NARCIS (Netherlands)

    Scheenen, T.W.J.; Vergeldt, F.J.; Windt, C.W.; Jager, de P.A.; As, van H.

    2001-01-01

    In this paper we present a pulse sequence that combines a displacement-encoded stimulated echo with rapid sampling of k-space by means of turbo spin echo imaging. The stimulated echo enables the use of long observation times between the two pulsed field gradients that sample q-space completely.

  2. Noise-bound method for detecting shadow-free scene changes in image sequences.

    Science.gov (United States)

    Irie, Kenji; McKinnon, Alan; Unsworth, Keith; Woodhead, Ian

    2010-02-01

    Many image processing applications are confounded by both sensor noise and cast shadows. All image sensors add noise to a captured image that can reduce algorithm sensitivity and performance, and global filters or fixed thresholds are often applied to limit their effects. Cast shadows can appear as scene changes and are difficult to adequately detect and remove from images and image sequences. We couple image-noise statistics with a dual-illumination shadow-detection algorithm to provide a novel color-based method for shadow-free scene-change detection whose performance is bound by metamerism and image noise, and has only one variable--the desired confidence interval for noise separation.

  3. Artificial Intelligence In Processing A Sequence Of Time-Varying Images

    Science.gov (United States)

    Siler, W.; Tucker, D.; Buckley, J.; Hess, R. G.; Powell, V. G.

    1985-04-01

    A computer system is described for unsupervised analysis of five sets of ultrasound images of the heart. Each set consists of 24 frames taken at 33 millisecond intervals. The images are acquired in real time with computer control of the ultrasound apparatus. After acquisition the images are segmented by a sequence of image-processing programs; features are extracted and stored in a version of the Carnegie- Mellon Blackboard. Region classification is accomplished by a fuzzy logic expert system FLOPS based on OPS5. Preliminary results are given.

  4. Parry-Romberg syndrome: findings in advanced magnetic resonance imaging sequences - case report

    Energy Technology Data Exchange (ETDEWEB)

    Paula, Rafael Alfenas de; Ribeiro, Bruno Niemeyer de Freitas, E-mail: alfenas85@gmail.com [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil). Hospital Universitario Clementino Fraga Filho; Bahia, Paulo Roberto Valle [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil). Dept. de radiologia; Ribeiro, Renato Niemeyer de Freitas [Hospital de Clinica de Jacarepagua, Rio de Janeiro, RJ (Brazil); Carvalho, Lais Balbi de [Universidade Presidente Antonio Carlos (Unipac), Juiz de Fora, MG (Brazil)

    2014-05-15

    Parry-Romberg syndrome is a rare disease characterized by progressive hemifacial atrophy associated with other systemic changes, including neurological symptoms. Currently, there are few studies exploring the utilization of advanced magnetic resonance sequences in the investigation of this disease. The authors report the case of a 45-year-old patient and describe the findings at structural magnetic resonance imaging and at advanced sequences, correlating them with pathophysiological data. (author)

  5. Head-motion-controlled video goggles: preliminary concept for an interactive laparoscopic image display (i-LID).

    Science.gov (United States)

    Aidlen, Jeremy T; Glick, Sara; Silverman, Kenneth; Silverman, Harvey F; Luks, Francois I

    2009-08-01

    Light-weight, low-profile, and high-resolution head-mounted displays (HMDs) now allow personalized viewing, of a laparoscopic image. The advantages include unobstructed viewing, regardless of position at the operating table, and the possibility to customize the image (i.e., enhanced reality, picture-in-picture, etc.). The bright image display allows use in daylight surroundings and the low profile of the HMD provides adequate peripheral vision. Theoretic disadvantages include reliance for all on the same image capture and anticues (i.e., reality disconnect) when the projected image remains static, despite changes in head position. This can lead to discomfort and even nausea. We have developed a prototype of interactive laparoscopic image display that allows hands-free control of the displayed image by changes in spatial orientation of the operator's head. The prototype consists of an HMD, a spatial orientation device, and computer software to enable hands-free panning and zooming of a video-endoscopic image display. The spatial orientation device uses magnetic fields created by a transmitter and receiver, each containing three orthogonal coils. The transmitter coils are efficiently driven, using USB power only, by a newly developed circuit, each at a unique frequency. The HMD-mounted receiver system links to a commercially available PC-interface PCI-bus sound card (M-Audiocard Delta 44; Avid Technology, Tewksbury, MA). Analog signals at the receiver are filtered, amplified, and converted to digital signals, which are processed to control the image display. The prototype uses a proprietary static fish-eye lens and software for the distortion-free reconstitution of any portion of the captured image. Left-right and up-down motions of the head (and HMD) produce real-time panning of the displayed image. Motion of the head toward, or away from, the transmitter causes real-time zooming in or out, respectively, of the displayed image. This prototype of the interactive HMD

  6. Video compression and DICOM proxies for remote viewing of DICOM images

    Science.gov (United States)

    Khorasani, Elahe; Sheinin, Vadim; Paulovicks, Brent; Jagmohan, Ashish

    2009-02-01

    Digital medical images are rapidly growing in size and volume. A typical study includes multiple image "slices." These images have a special format and a communication protocol referred to as DICOM (Digital Imaging Communications in Medicine). Storing, retrieving, and viewing these images are handled by DICOM-enabled systems. DICOM images are stored in central repository servers called PACS (Picture Archival and Communication Systems). Remote viewing stations are DICOM-enabled applications that can query the PACS servers and retrieve the DICOM images for viewing. Modern medical images are quite large, reaching as much as 1 GB per file. When the viewing station is connected to the PACS server via a high-bandwidth local LAN, downloading of the images is relatively efficient and does not cause significant wasted time for physicians. Problems arise when the viewing station is located in a remote facility that has a low-bandwidth link to the PACS server. If the link between the PACS and remote facility is in the range of 1 Mbit/sec, downloading medical images is very slow. To overcome this problem, medical images are compressed to reduce the size for transmission. This paper describes a method of compression that maintains diagnostic quality of images while significantly reducing the volume to be transmitted, without any change to the existing PACS servers and viewer software, and without requiring any change in the way doctors retrieve and view images today.

  7. Modelling retinal pulsatile blood flow from video data.

    Science.gov (United States)

    Betz-Stablein, Brigid; Hazelton, Martin L; Morgan, William H

    2016-09-01

    Modern day datasets continue to increase in both size and diversity. One example of such 'big data' is video data. Within the medical arena, more disciplines are using video as a diagnostic tool. Given the large amount of data stored within a video image, it is one of most time consuming types of data to process and analyse. Therefore, it is desirable to have automated techniques to extract, process and analyse data from video images. While many methods have been developed for extracting and processing video data, statistical modelling to analyse the outputted data has rarely been employed. We develop a method to take a video sequence of periodic nature, extract the RGB data and model the changes occurring across the contiguous images. We employ harmonic regression to model periodicity with autoregressive terms accounting for the error process associated with the time series nature of the data. A linear spline is included to account for movement between frames. We apply this model to video sequences of retinal vessel pulsation, which is the pulsatile component of blood flow. Slope and amplitude are calculated for the curves generated from the application of the harmonic model, providing clinical insight into the location of obstruction within the retinal vessels. The method can be applied to individual vessels, or to smaller segments such as 2 × 2 pixels which can then be interpreted easily as a heat map. © The Author(s) 2016.

  8. MR imaging with fluid attenuated inversion recovery sequence of childhood adrenoleukodystrophy : comparison with T2 weighted spin echo imaging

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Asiry; Seo, Jeong-Jin; Jeong, Gwang Woo; Chung, Tae Woong; Jeong, Yong Yeon; Kang, Heoung Keun; Kook, Hoon; Woo, Young Jong; Hwang, Tai Joo [Chonnam Univ. Medical School, Seoul (Korea, Republic of)

    1999-03-01

    The purpose of this study was to evaluate the usefulness of FLAIR(Fluid Attenuated Inversion Recovery) MR imaging in childhood adrenoleukodystrophy by comparing with those of T2-weighted FSE imaging, and to correlate MRI findings with clinical manifestations. Axial FLAIR images(TR/TE/TI=10004/123/2200) and T2-weighted FSE images(TR/TE=4000/104) of brain in six male patients(age range : 6-17 years, mean age : 10.2 years) with biochemically confirmed adrenoleukodystrophy were compared visually by two radiologists for detection, conspicuity, and the extent of lesion. Quantitatively, we compared lesion/CSF contrast, lesion/CSF contrast to noise ratio(CNR), lesion/white matter(WM) contrast, and lesion/WM CNR between FLAIR and T2 weighted image. We correlated MR findings with clinical manifestations of neurologic symptoms and evaluated whether MRI could detect white matter lesions in neurologically asymptomatic patients. Visual detection of lesions was better with FLAIR images in 2 of the 6 cases and it was equal in the remainders. Visual conspicuity and detection of the extent of lesion were superior on FLAIR images than T2-weighted images in all 6 cases. In the quantitative assessment of lesions, FLAIR was superior to T2-weighted image for lesion/CSF contrast and lesion/CSF CNR, but was inferior to T2 weighted image for lesion/WM contrast and lesion/WM CNR. In one case, FLAIR images distinguished the portion of encephalomalacic change from lesions. MR findings of adrenoleukodystrophy were correlated with clinical manifestations in symptomatic 4 cases, and also detected white matter lesions in asymptomatic 2 cases. MR imaging with FLAIR sequence provided images that were equal or superior to T2-weighted images in the evaluation of childhood adrenoleukodystrophy. MRI findings were well correlated with clinical manifestations and could detect white matter lesions in neurologically asymptomatic adrenoleukodystrophy patients.

  9. Approach for moving small target detection in infrared image sequence based on reinforcement learning

    Science.gov (United States)

    Wang, Chuanyun; Qin, Shiyin

    2016-09-01

    Addressing the problems of moving small target detection in infrared image sequence caused by background clutter and target size variation with time, an approach for moving small target detection is proposed under a pipeline framework with an optimization strategy based on reinforcement learning. The pipeline framework is composed by pipeline establishment, target-background images separation, and target confirmation, in which the pipeline is established by designating several successive images with temporal sliding window, target-background images separation is dealt with low-rank and sparse matrix decomposition via robust principal component analysis, and target confirmation is achieved by employing a voting mechanism over more than one separated target images of the same input image. For unremitting optimization of target-background images separation, the weighting parameter of low-rank and sparse matrix decomposition is dynamically regulated by the way of reinforcement learning in consecutive detection, in which the complexity evaluation from sequential infrared images and results assessment of moving small target detection are integrated. The experiment results over four infrared small target image sequences with different cloudy sky backgrounds demonstrate the effectiveness and advantages of the proposed approach in both background clutter suppression and small target detection.

  10. Iteration and superposition encryption scheme for image sequences based on multi-dimensional keys

    Science.gov (United States)

    Han, Chao; Shen, Yuzhen; Ma, Wenlin

    2017-12-01

    An iteration and superposition encryption scheme for image sequences based on multi-dimensional keys is proposed for high security, big capacity and low noise information transmission. Multiple images to be encrypted are transformed into phase-only images with the iterative algorithm and then are encrypted by different random phase, respectively. The encrypted phase-only images are performed by inverse Fourier transform, respectively, thus new object functions are generated. The new functions are located in different blocks and padded zero for a sparse distribution, then they propagate to a specific region at different distances by angular spectrum diffraction, respectively and are superposed in order to form a single image. The single image is multiplied with a random phase in the frequency domain and then the phase part of the frequency spectrums is truncated and the amplitude information is reserved. The random phase, propagation distances, truncated phase information in frequency domain are employed as multiple dimensional keys. The iteration processing and sparse distribution greatly reduce the crosstalk among the multiple encryption images. The superposition of image sequences greatly improves the capacity of encrypted information. Several numerical experiments based on a designed optical system demonstrate that the proposed scheme can enhance encrypted information capacity and make image transmission at a highly desired security level.

  11. Cryptanalysis of an Image Encryption Algorithm Based on DNA Sequence Operation and Hyper-chaotic System

    Science.gov (United States)

    Xu, Ming

    2017-06-01

    Recently, chaotic image cipher using DNA sequence operation has been studied extensively. However, corresponding cryptanalysis is lacking, which impedes its further development. This paper cryptanalyzes a newly proposed chaotic image cipher based on DNA sequence operation. In this paper, we firstly analyze the security defects of the proposal. Then by applying chosen-plaintext attack, we show that all the secret parameters can be revealed. The effectiveness of the proposed chosen-plaintext attack is supported both by rigorous theoretical analysis and experimental results.

  12. Ultrasonic Shear Wave Elasticity Imaging (SWEI) Sequencing and Data Processing Using a Verasonics Research Scanner.

    Science.gov (United States)

    Deng, Yufeng; Rouze, Ned C; Palmeri, Mark L; Nightingale, Kathryn R

    2016-10-03

    Ultrasound elasticity imaging has been developed over the last decade to estimate tissue stiffness. Shear wave elasticity imaging (SWEI) quantifies tissue stiffness by measuring the speed of propagating shear waves following acoustic radiation force excitation. This work presents the sequencing and data processing protocols of SWEI using a Verasonics system. The selection of the sequence parameters in a Verasonics programming script is discussed in detail. The data processing pipeline to calculate group shear wave speed (SWS), including tissue motion estimation, data filtering, and SWS estimation is demonstrated. In addition, the procedures for calibration of beam position, scanner timing, and transducer face heating are provided to avoid SWS measurement bias and transducer damage.

  13. Ultrasonic Shear Wave Elasticity Imaging Sequencing and Data Processing Using a Verasonics Research Scanner.

    Science.gov (United States)

    Deng, Yufeng; Rouze, Ned C; Palmeri, Mark L; Nightingale, Kathryn R

    2017-01-01

    Ultrasound elasticity imaging has been developed over the last decade to estimate tissue stiffness. Shear wave elasticity imaging (SWEI) quantifies tissue stiffness by measuring the speed of propagating shear waves following acoustic radiation force excitation. This paper presents the sequencing and data processing protocols of SWEI using a Verasonics system. The selection of the sequence parameters in a Verasonics programming script is discussed in detail. The data processing pipeline to calculate group shear wave speed (SWS), including tissue motion estimation, data filtering, and SWS estimation, is demonstrated. In addition, the procedures for calibration of beam position, scanner timing, and transducer face heating are provided to avoid SWS measurement bias and transducer damage.

  14. Endoscopic Trimodal Imaging Detects Colonic Neoplasia as Well as Standard Video Endoscopy

    NARCIS (Netherlands)

    Kuiper, Teaco; van den Broek, Frank J. C.; Naber, Anton H.; van Soest, Ellert J.; Scholten, Pieter; Mallant-Hent, Rosalie Ch; van den Brande, Jan; Jansen, Jeroen M.; van Oijen, Arnoud H. A. M.; Marsman, Willem A.; Bergman, Jacques J. G. H. M.; Fockens, Paul; Dekker, Evelien

    2011-01-01

    BACKGROUND & AIMS: Endoscopic trimodal imaging (ETMI) is a novel endoscopic technique that combines high-resolution endoscopy (HRE), autofluorescence imaging (AFI), and narrow-band imaging (NBI) that has only been studied in academic settings. We performed a randomized, controlled trial in a

  15. Denoising time-resolved microscopy image sequences with singular value thresholding

    Energy Technology Data Exchange (ETDEWEB)

    Furnival, Tom, E-mail: tjof2@cam.ac.uk; Leary, Rowan K., E-mail: rkl26@cam.ac.uk; Midgley, Paul A., E-mail: pam33@cam.ac.uk

    2017-07-15

    Time-resolved imaging in microscopy is important for the direct observation of a range of dynamic processes in both the physical and life sciences. However, the image sequences are often corrupted by noise, either as a result of high frame rates or a need to limit the radiation dose received by the sample. Here we exploit both spatial and temporal correlations using low-rank matrix recovery methods to denoise microscopy image sequences. We also make use of an unbiased risk estimator to address the issue of how much thresholding to apply in a robust and automated manner. The performance of the technique is demonstrated using simulated image sequences, as well as experimental scanning transmission electron microscopy data, where surface adatom motion and nanoparticle structural dynamics are recovered at rates of up to 32 frames per second. - Highlights: • Correlations in space and time are harnessed to denoise microscopy image sequences. • A robust estimator provides automated selection of the denoising parameter. • Motion tracking and automated noise estimation provides a versatile algorithm. • Application to time-resolved STEM enables study of atomic and nanoparticle dynamics.

  16. Rapid 3D Reconstruction for Image Sequence Acquired from UAV Camera

    Directory of Open Access Journals (Sweden)

    Yufu Qu

    2018-01-01

    Full Text Available In order to reconstruct three-dimensional (3D structures from an image sequence captured by unmanned aerial vehicles’ camera (UAVs and improve the processing speed, we propose a rapid 3D reconstruction method that is based on an image queue, considering the continuity and relevance of UAV camera images. The proposed approach first compresses the feature points of each image into three principal component points by using the principal component analysis method. In order to select the key images suitable for 3D reconstruction, the principal component points are used to estimate the interrelationships between images. Second, these key images are inserted into a fixed-length image queue. The positions and orientations of the images are calculated, and the 3D coordinates of the feature points are estimated using weighted bundle adjustment. With this structural information, the depth maps of these images can be calculated. Next, we update the image queue by deleting some of the old images and inserting some new images into the queue, and a structural calculation of all the images can be performed by repeating the previous steps. Finally, a dense 3D point cloud can be obtained using the depth–map fusion method. The experimental results indicate that when the texture of the images is complex and the number of images exceeds 100, the proposed method can improve the calculation speed by more than a factor of four with almost no loss of precision. Furthermore, as the number of images increases, the improvement in the calculation speed will become more noticeable.

  17. Rapid 3D Reconstruction for Image Sequence Acquired from UAV Camera.

    Science.gov (United States)

    Qu, Yufu; Huang, Jianyu; Zhang, Xuan

    2018-01-14

    In order to reconstruct three-dimensional (3D) structures from an image sequence captured by unmanned aerial vehicles' camera (UAVs) and improve the processing speed, we propose a rapid 3D reconstruction method that is based on an image queue, considering the continuity and relevance of UAV camera images. The proposed approach first compresses the feature points of each image into three principal component points by using the principal component analysis method. In order to select the key images suitable for 3D reconstruction, the principal component points are used to estimate the interrelationships between images. Second, these key images are inserted into a fixed-length image queue. The positions and orientations of the images are calculated, and the 3D coordinates of the feature points are estimated using weighted bundle adjustment. With this structural information, the depth maps of these images can be calculated. Next, we update the image queue by deleting some of the old images and inserting some new images into the queue, and a structural calculation of all the images can be performed by repeating the previous steps. Finally, a dense 3D point cloud can be obtained using the depth-map fusion method. The experimental results indicate that when the texture of the images is complex and the number of images exceeds 100, the proposed method can improve the calculation speed by more than a factor of four with almost no loss of precision. Furthermore, as the number of images increases, the improvement in the calculation speed will become more noticeable.

  18. Estimation of temporal evolution of the helium plasmasphere based on a sequence of IMAGE/EUV images

    Science.gov (United States)

    Nakano, S.; Fok, M.-C.; Brandt, P. C.; Higuchi, T.

    2014-05-01

    We have developed a technique for estimating the temporal evolution of the plasmaspheric helium ion density based on a sequence of extreme ultraviolet (EUV) data obtained from the IMAGE satellite. In the proposed technique, the estimation is obtained by incorporating EUV images from IMAGE into a two-dimensional fluid model of the plasmasphere using a data assimilation approach based on the ensemble transform Kalman filter. Since the motion and the spatial structure of the helium plasmasphere is strongly controlled by the electric field in the inner magnetosphere, the electric field around the plasmapause can also be estimated using the ensemble transform Kalman filter. We performed an experiment using synthetic images that were generated from the same numerical model under a certain condition. It was confirmed that the condition that generated the synthetic images was successfully reproduced. We also present some results obtained using real EUV imaging data. Finally, we discuss the possibility of estimating the density profile along a magnetic field line. Since each EUV image was taken from a different direction due to the motion of the IMAGE satellite, we could obtain the information on the density profile along a field line by combining multiple images.

  19. Cardiac tumors: optimal cardiac MR sequences and spectrum of imaging appearances.

    LENUS (Irish Health Repository)

    O'Donnell, David H

    2012-02-01

    OBJECTIVE: This article reviews the optimal cardiac MRI sequences for and the spectrum of imaging appearances of cardiac tumors. CONCLUSION: Recent technologic advances in cardiac MRI have resulted in the rapid acquisition of images of the heart with high spatial and temporal resolution and excellent myocardial tissue characterization. Cardiac MRI provides optimal assessment of the location, functional characteristics, and soft-tissue features of cardiac tumors, allowing accurate differentiation of benign and malignant lesions.

  20. Intraoperative stereoscopic 3D video imaging: pushing the boundaries of surgical visualisation and applications for neurosurgical education.

    Science.gov (United States)

    Heath, Michael D; Cohen-Gadol, Aaron A

    2012-10-01

    In the past decades, we have witnessed waves of interest in three-dimensional (3D) stereoscopic imaging. Previously, the complexity associated with 3D technology led to its absence in the operating room. But recently, the public's resurrection of interest in this imaging modality has revived its exploration in surgery. Technological advances have also paved the way for incorporation of 3D stereoscopic imaging in neurosurgical education. Herein, the authors discuss the advantages of intraoperative 3D recording and display for neurosurgical learning and contemplate its future directions based on their experience with 3D technology and a review of the literature. Potential benefits of stereoscopic displays include an enhancement of subjective image quality, proper identification of the structure of interest from surrounding tissues and improved surface detection and depth judgment. Such benefits are critical during the intraoperative decision-making process and proper handling of the lesion (specifically, for surgery on aneurysms and tumours), and should therefore be available to the observers in the operating room and residents in training. Our trainees can relive the intraoperative experience of the primary surgeon by reviewing the recorded stereoscopic 3D videos. Proper 3D knowledge of surgical anatomy is important for operative success. 3D stereoscopic viewing of this anatomy may accelerate the learning curve of trainees and improve the standards of surgical teaching. More objective studies are relevant in further establishing the value of 3D technology in neurosurgical education.

  1. Efficient video panoramic image stitching based on an improved selection of Harris corners and a multiple-constraint corner matching.

    Directory of Open Access Journals (Sweden)

    Minchen Zhu

    Full Text Available Video panoramic image stitching is extremely time-consuming among other challenges. We present a new algorithm: (i Improved, self-adaptive selection of Harris corners. The successful stitching relies heavily on the accuracy of corner selection. We fragment each image into numerous regions and select corners within each region according to the normalized variance of region grayscales. Such a selection is self-adaptive and guarantees that corners are distributed proportional to region texture information. The possible clustering of corners is also avoided. (ii Multiple-constraint corner matching. The traditional Random Sample Consensus (RANSAC algorithm is inefficient, especially when handling a large number of images with similar features. We filter out many inappropriate corners according to their position information, and then generate candidate matching pairs based on grayscales of adjacent regions around corners. Finally we apply multiple constraints on every two pairs to remove incorrectly matched pairs. By a significantly reduced number of iterations needed in RANSAC, the stitching can be performed in a much more efficient manner. Experiments demonstrate that (i our corner matching is four times faster than normalized cross-correlation function (NCC rough match in RANSAC and (ii generated panoramas feature a smooth transition in overlapping image areas and satisfy real-time human visual requirements.

  2. Assessment of the Potential of UAV Video Image Analysis for Planning Irrigation Needs of Golf Courses

    Directory of Open Access Journals (Sweden)

    Alberto-Jesús Perea-Moreno

    2016-12-01

    Full Text Available Golf courses can be considered as precision agriculture, as being a playing surface, their appearance is of vital importance. Areas with good weather tend to have low rainfall. Therefore, the water management of golf courses in these climates is a crucial issue due to the high water demand of turfgrass. Golf courses are rapidly transitioning to reuse water, e.g., the municipalities in the USA are providing price incentives or mandate the use of reuse water for irrigation purposes; in Europe this is mandatory. So, knowing the turfgrass surfaces of a large area can help plan the treated sewage effluent needs. Recycled water is usually of poor quality, thus it is crucial to check the real turfgrass surface in order to be able to plan the global irrigation needs using this type of water. In this way, the irrigation of golf courses does not detract from the natural water resources of the area. The aim of this paper is to propose a new methodology for analysing geometric patterns of video data acquired from UAVs (Unmanned Aerial Vehicle using a new Hierarchical Temporal Memory (HTM algorithm. A case study concerning maintained turfgrass, especially for golf courses, has been developed. It shows very good results, better than 98% in the confusion matrix. The results obtained in this study represent a first step toward video imagery classification. In summary, technical progress in computing power and software has shown that video imagery is one of the most promising environmental data acquisition techniques available today. This rapid classification of turfgrass can play an important role for planning water management.

  3. Limited-sequence magnetic resonance imaging in the evaluation of the ultrasonographically indeterminate pelvic mass

    Energy Technology Data Exchange (ETDEWEB)

    Chang, S.D. [Univ. of British Columbia, Vancouver Hospital and Helath Services Centre, Dept. of Radiology, Vancouver, British Columbia (Canada)]. E-mail: schang@vanhosp.bc.ca; Cooperberg, P.L.; Wong, A.D. [Univ. of British Columbia, St. Paul' s Hospital, Dept. of Radiology, Vancouver, British Columbia (Canada); Llewellyn, P.A. [Lion' s Gate Hospital, Dept. of Radiology, North Vancouver, British Columbia (Canada); Bilbey, J.H. [Royal Inland Hospital, Dept. of Radiology, Kamloops, British Columbia (Canada)

    2004-04-01

    To evaluate the usefulness of limited-sequence magnetic resonance imaging (MRI) in the elucidation of ultrasonographically indeterminate pelvic masses. This study focused only on pelvic masses in which the origin of the mass (uterine v. extrauterine) could not be determined by ultrasonography (US). The origin of a pelvic mass has clinical implications. A mass arising from the uterus is most likely to be a leiomyoma, which is a benign lesion, whereas an extrauterine mass will have a higher likelihood of malignancy and usually requires surgery. Eighty-one female patients whose pelvic mass was of indeterminate origin on US also underwent limited-sequence MRI of the pelvis. Most of the MRI examinations were performed on the same day as the US. Limited-sequence MRI sequences included a quick gradient-echoT{sub 1}-weighted localizer and a fast spin-echoT{sub 2}-weighted sequence. Final diagnoses were established by surgical pathology or by clinical and imaging follow-up. Limited-sequence MRI was helpful in 79 of the 81 cases (98%). Fifty-two of the 81 masses (64%) were leiomyomas. One was a leiomyosarcoma. The extrauterine masses (26/81 [32%]) were identified as 14 ovarian malignancies, 4 endometriomas, 3 dermoids, an ovarian fibroma, an infarcted fibrothecoma, an infarcted hemorrhagic cyst, a sigmoid diverticular abscess and a gastrointestinal stromal tumour of the ileum. In the other 2 cases (2/81 [2%]), the origin of the pelvic mass remained indeterminate. Both of these indeterminate masses showed low signal onT{sub 2}-weighted images and were interpreted as probable leiomyomas. They were not surgically removed but were followed clinically and had a stable course. Limited-sequence MRI is a quick and efficient way to further evaluate ultrasonographically indeterminate pelvic masses. Limited-sequence MRI of the pelvis can suffice, in these cases, without requiring a full MRI examination. (author)

  4. A New Distance Measure Based on Generalized Image Normalized Cross-Correlation for Robust Video Tracking and Image Recognition.

    Science.gov (United States)

    Nakhmani, Arie; Tannenbaum, Allen

    2013-02-01

    We propose two novel distance measures, normalized between 0 and 1, and based on normalized cross-correlation for image matching. These distance measures explicitly utilize the fact that for natural images there is a high correlation between spatially close pixels. Image matching is used in various computer vision tasks, and the requirements to the distance measure are application dependent. Image recognition applications require more shift and rotation robust measures. In contrast, registration and tracking applications require better localization and noise tolerance. In this paper, we explore different advantages of our distance measures, and compare them to other popular measures, including Normalized Cross-Correlation (NCC) and Image Euclidean Distance (IMED). We show which of the proposed measures is more appropriate for tracking, and which is appropriate for image recognition tasks.

  5. Moving Shadow Detection in Video Using Cepstrum

    Directory of Open Access Journals (Sweden)

    Fuat Cogun

    2013-01-01

    Full Text Available Moving shadows constitute problems in various applications such as image segmentation and object tracking. The main cause of these problems is the misclassification of the shadow pixels as target pixels. Therefore, the use of an accurate and reliable shadow detection method is essential to realize intelligent video processing applications. In this paper, a cepstrum-based method for moving shadow detection is presented. The proposed method is tested on outdoor and indoor video sequences using well-known benchmark test sets. To show the improvements over previous approaches, quantitative metrics are introduced and comparisons based on these metrics are made.

  6. The effects of physique-salient and physique non-salient exercise videos on women's body image, self-presentational concerns, and exercise motivation.

    Science.gov (United States)

    Ginis, Kathleen A Martin; Prapavessis, Harry; Haase, Anne M

    2008-06-01

    This experiment examined the effects of exposure to physique-salient (PS) and physique non-salient (PNS) exercise videos and the moderating influence of perceived physique discrepancies, on body image, self-presentational concerns, and exercise motivation. Eighty inactive women (M age=26) exercised to a 30 min instructional exercise video. In the PS condition, the video instructor wore revealing attire that emphasized her thin and toned physique. In the PNS condition, she wore attire that concealed her physique. Participants completed pre- and post-exercise measures of body image, social physique anxiety (SPA) and self-presentational efficacy (SPE) and a post-exercise measure of exercise motivation and perceived discrepancies with the instructor's body. No main or moderated effects emerged for video condition. However, greater perceived negative discrepancies were associated with poorer post-exercise body satisfaction and body evaluations, and higher state SPA. There were no effects on SPE or motivation. Results suggest that exercise videos that elicit perceived negative discrepancies can be detrimental to women's body images.

  7. Image-model coupling: a simple information theoretic perspective for image sequences

    Directory of Open Access Journals (Sweden)

    N. D. Smith

    2009-03-01

    Full Text Available Images are widely used to visualise physical processes. Models may be developed which attempt to replicate those processes and their effects. The technique of coupling model output to images, which is here called "image-model coupling", may be used to help understand the underlying physical processes, and better understand the limitations of the models. An information theoretic framework is presented for image-model coupling in the context of communication along a discrete channel. The physical process may be regarded as a transmitter of images and the model as part of a receiver which decodes or recognises those images. Image-model coupling may therefore be interpreted as image recognition. Of interest are physical processes which exhibit "memory". The response of such a system is not only dependent on the current values of driver variables, but also on the recent history of drivers and/or system description. Examples of such systems in geophysics include the ionosphere and Earth's climate. The discrete channel model is used to help derive expressions for matching images and model output, and help analyse the coupling.

  8. Image-model coupling: a simple information theoretic perspective for image sequences

    Science.gov (United States)

    Smith, N. D.; Mitchell, C. N.; Budd, C. J.

    2009-03-01

    Images are widely used to visualise physical processes. Models may be developed which attempt to replicate those processes and their effects. The technique of coupling model output to images, which is here called "image-model coupling", may be used to help understand the underlying physical processes, and better understand the limitations of the models. An information theoretic framework is presented for image-model coupling in the context of communication along a discrete channel. The physical process may be regarded as a transmitter of images and the model as part of a receiver which decodes or recognises those images. Image-model coupling may therefore be interpreted as image recognition. Of interest are physical processes which exhibit "memory". The response of such a system is not only dependent on the current values of driver variables, but also on the recent history of drivers and/or system description. Examples of such systems in geophysics include the ionosphere and Earth's climate. The discrete channel model is used to help derive expressions for matching images and model output, and help analyse the coupling.

  9. Live cell imaging of repetitive DNA sequences via GFP-tagged polydactyl zinc finger proteins

    Science.gov (United States)

    Lindhout, Beatrice I.; Fransz, Paul; Tessadori, Federico; Meckel, Tobias; Hooykaas, Paul J.J.; van der Zaal, Bert J.

    2007-01-01

    Several techniques are available to study chromosomes or chromosomal domains in nuclei of chemically fixed or living cells. Current methods to detect DNA sequences in vivo are limited to trans interactions between a DNA sequence and a transcription factor from natural systems. Here, we expand live cell imaging tools using a novel approach based on zinc finger-DNA recognition codes. We constructed several polydactyl zinc finger (PZF) DNA-binding domains aimed to recognize specific DNA sequences in Arabidopsis and mouse and fused these with GFP. Plants and mouse cells expressing PZF:GFP proteins were subsequently analyzed by confocal microscopy. For Arabidopsis, we designed a PZF:GFP protein aimed to specifically recognize a 9-bp sequence within centromeric 180-bp repeat and monitored centromeres in living roots. Similarly, in mouse cells a PZF:GFP protein was targeted to a 9-bp sequence in the major satellite repeat. Both PZF:GFP proteins localized in chromocenters which represent heterochromatin domains containing centromere and other tandem repeats. The number of PZF:GFP molecules per centromere in Arabidopsis, quantified with near single-molecule precision, approximated the number of expected binding sites. Our data demonstrate that live cell imaging of specific DNA sequences can be achieved with artificial zinc finger proteins in different organisms. PMID:17704126

  10. Use of 64 kbits/s digital channel for image transmission: Using low scan two-way video

    Science.gov (United States)

    Rahko, K.; Hongyan, L.; Kley, M.; Peuhkuri, M.; Rahko, M.

    1993-09-01

    At the seminar 'Competition in Telecommunications in Finland' on September 3rd, 1993, a test of two-way transferring an image by using 64 kbits/s digital channel was carried out. With the help of the Helsinki Telephone Company, a portrait was transferred to the lecture hall by using Vistacom Videophones, Nokia and Siemens ISDN exchange, as well as Nokia's and Siemens' user terminal equipment. It was shown on a screen through a video projector, so all visitors could see it. For human factors in telecommunications studies, every attendee was asked to give comments about the transferring quality. The report presents the results of the survey and a brief assessment of the technology.

  11. Integrating Illumination, Motion, and Shape Models for Robust Face Recognition in Video

    Directory of Open Access Journals (Sweden)

    Keyur Patel

    2008-05-01

    Full Text Available The use of video sequences for face recognition has been relatively less studied compared to image-based approaches. In this paper, we present an analysis-by-synthesis framework for face recognition from video sequences that is robust to large changes in facial pose and lighting conditions. This requires tracking the video sequence, as well as recognition algorithms that are able to integrate information over the entire video; we address both these problems. Our method is based on a recently obtained theoretical result that can integrate the effects of motion, lighting, and shape in generating an image using a perspective camera. This result can be used to estimate the pose and structure of the face and the illumination conditions for each frame in a video sequence in the presence of multiple point and extended light sources. We propose a new inverse compositional estimation approach for this purpose. We then synthesize images using the face model estimated from the training data corresponding to the conditions in the probe sequences. Similarity between the synthesized and the probe images is computed using suitable distance measurements. The method can handle situations where the pose and lighting conditions in the training and testing data are completely disjoint. We show detailed performance analysis results and recognition scores on a large video dataset.

  12. Single-heartbeat electromechanical wave imaging with optimal strain estimation using temporally unequispaced acquisition sequences.

    Science.gov (United States)

    Provost, Jean; Thiébaut, Stéphane; Luo, Jianwen; Konofagou, Elisa E

    2012-02-21

    Electromechanical Wave Imaging (EWI) is a non-invasive, ultrasound-based imaging method capable of mapping the electromechanical wave (EW) in vivo, i.e. the transient deformations occurring in response to the electrical activation of the heart. Optimal imaging frame rates, in terms of the elastographic signal-to-noise ratio, to capture the EW cannot be achieved due to the limitations of conventional imaging sequences, in which the frame rate is low and tied to the imaging parameters. To achieve higher frame rates, EWI is typically performed by combining sectors acquired during separate heartbeats, which are then combined into a single view. However, the frame rates achieved remain potentially sub-optimal and this approach precludes the study of non-periodic arrhythmias. This paper describes a temporally unequispaced acquisition sequence (TUAS) for which a wide range of frame rates are achievable independently of the imaging parameters, while maintaining a full view of the heart at high beam density. TUAS is first used to determine the optimal frame rate for EWI in a paced canine heart in vivo and then to image during ventricular fibrillation. These results indicate how EWI can be optimally performed within a single heartbeat, during free breathing and in real time, for both periodic and non-periodic cardiac events.

  13. Activity Detection and Retrieval for Image and Video Data with Limited Training

    Science.gov (United States)

    2015-06-10

    Number of graduating undergraduates funded by a DoD funded Center of Excellence grant for Education , Research and Engineering: The number of...geometric snakes to segment the image into constant intensity regions. The Chan-Vese framework proposes to partition the image f()(x ∈  Ω ⊆ ℝ

  14. SCALE-PWI: A pulse sequence for absolute quantitative cerebral perfusion imaging.

    Science.gov (United States)

    Srour, Jessy Mouannes; Shin, Wanyong; Shah, Saurabh; Sen, Anindya; Carroll, Timothy J

    2011-05-01

    The Bookend technique is a magnetic resonance imaging (MRI) dynamic susceptibility contrast method that provides reliable quantitative measurement of cerebral blood flow (CBF) and cerebral blood volume (CBV). The quantification is patient specific, is derived from a steady-state measurement of CBV, and is obtained from T(1) changes in the white matter and the blood pool after contrast agent injection. In the current implementation, the Bookend technique consists of three scanning steps requiring a cumulative scan time of 3 minutes 47 seconds, a well-trained technologist, and extra time for offline image reconstruction. We present an automation and acceleration of the multiscan Bookend protocol through a self-calibrating pulse sequence, namely Self-Calibrated Epi Perfusion-Weighted Imaging (SCALE-PWI). The SCALE-PWI is a single-shot echo-planar imaging pulse sequence with three modules and a total scan time of under 2 minutes. It provides the possibility of performing online, quantitative perfusion image reconstruction, which reduces the latency to obtain quantitative maps. A validation study in healthy volunteers (N=19) showed excellent agreement between SCALE-PWI and the conventional Bookend protocol (P>0.05 with Student's t-test, r=0.95/slope=0.98 for quantitative CBF, and r=0.91/slope=0.94 for quantitative CBV). A single MRI pulse sequence for absolute quantification of cerebral perfusion has been developed.

  15. Target recognition and scene interpretation in image/video understanding systems based on network-symbolic models

    Science.gov (United States)

    Kuvich, Gary

    2004-08-01

    Vision is only a part of a system that converts visual information into knowledge structures. These structures drive the vision process, resolving ambiguity and uncertainty via feedback, and provide image understanding, which is an interpretation of visual information in terms of these knowledge models. These mechanisms provide a reliable recognition if the object is occluded or cannot be recognized as a whole. It is hard to split the entire system apart, and reliable solutions to the target recognition problems are possible only within the solution of a more generic Image Understanding Problem. Brain reduces informational and computational complexities, using implicit symbolic coding of features, hierarchical compression, and selective processing of visual information. Biologically inspired Network-Symbolic representation, where both systematic structural/logical methods and neural/statistical methods are parts of a single mechanism, is the most feasible for such models. It converts visual information into relational Network-Symbolic structures, avoiding artificial precise computations of 3-dimensional models. Network-Symbolic Transformations derive abstract structures, which allows for invariant recognition of an object as exemplar of a class. Active vision helps creating consistent models. Attention, separation of figure from ground and perceptual grouping are special kinds of network-symbolic transformations. Such Image/Video Understanding Systems will be reliably recognizing targets.

  16. Target recognition with image/video understanding systems based on active vision principle and network-symbolic models

    Science.gov (United States)

    Kuvich, Gary

    2004-08-01

    Vision is only a part of a larger system that converts visual information into knowledge structures. These structures drive the vision process, resolving ambiguity and uncertainty via feedback, and provide image understanding, which is an interpretation of visual information in terms of these knowledge models. This mechanism provides a reliable recognition if the target is occluded or cannot be recognized. It is hard to split the entire system apart, and reliable solutions to the target recognition problems are possible only within the solution of a more generic Image Understanding Problem. Brain reduces informational and computational complexities, using implicit symbolic coding of features, hierarchical compression, and selective processing of visual information. Biologically inspired Network-Symbolic representation, where both systematic structural/logical methods and neural/statistical methods are parts of a single mechanism, converts visual information into relational Network-Symbolic structures, avoiding artificial precise computations of 3-dimensional models. Logic of visual scenes can be captured in Network-Symbolic models and used for disambiguation of visual information. Network-Symbolic Transformations derive abstract structures, which allow for invariant recognition of an object as exemplar of a class. Active vision helps build consistent, unambiguous models. Such Image/Video Understanding Systems will be able reliably recognizing targets in real-world conditions.

  17. Seven neurons memorizing sequences of alphabetical images via spike-timing dependent plasticity.

    Science.gov (United States)

    Osogami, Takayuki; Otsuka, Makoto

    2015-09-16

    An artificial neural network, such as a Boltzmann machine, can be trained with the Hebb rule so that it stores static patterns and retrieves a particular pattern when an associated cue is presented to it. Such a network, however, cannot effectively deal with dynamic patterns in the manner of living creatures. Here, we design a dynamic Boltzmann machine (DyBM) and a learning rule that has some of the properties of spike-timing dependent plasticity (STDP), which has been postulated for biological neural networks. We train a DyBM consisting of only seven neurons in a way that it memorizes the sequence of the bitmap patterns in an alphabetical image "SCIENCE" and its reverse sequence and retrieves either sequence when a partial sequence is presented as a cue. The DyBM is to STDP as the Boltzmann machine is to the Hebb rule.

  18. Magnetic resonance imaging of the Achilles tendon using ultrashort TE (UTE) pulse sequences

    Energy Technology Data Exchange (ETDEWEB)

    Robson, M.D.; Benjamin, M.; Gishen, P.; Bydder, G.M. E-mail: gbydder@ucsd.edu

    2004-08-01

    AIM: To assess the potential value of imaging the Achilles tendon with ultrashort echo time (UTE) pulse sequences. MATERIALS AND METHODS: Four normal controls and four patients with chronic Achilles tendinopathy were examined in the sagittal and transverse planes. Three of the patients were examined before and after intravenous gadodiamide. RESULTS: The fascicular pattern was clearly demonstrated within the tendon and detail of the three distinct fibrocartilaginous components of an 'enthesis organ' was well seen. T2* measurements showed two short T2* components. Increase in long T2 components with reduction in short T2 components was seen in tendinopathy. Contrast enhancement was much more extensive than with conventional sequences in two cases of tendinopathy but in a third case, there was a region of reduced enhancement. CONCLUSION: UTE pulse sequences provide anatomical detail not apparent with conventional sequences, demonstrate differences in T2* and show patterns of both increased and decreased enhancement in tendinopathy.

  19. Learning Trajectory for Transforming Teachers' Knowledge for Teaching Mathematics and Science with Digital Image and Video Technologies in an Online Learning Experience

    Science.gov (United States)

    Niess, Margaret L.; Gillow-Wiles, Henry

    2014-01-01

    This qualitative cross-case study explores the influence of a designed learning trajectory on transforming teachers' technological pedagogical content knowledge (TPACK) for teaching with digital image and video technologies. The TPACK Learning Trajectory embeds tasks with specific instructional strategies within a social metacognitive…

  20. Global adjustment for creating extended panoramic images in video-dermoscopy

    Science.gov (United States)

    Faraz, Khuram; Blondel, Walter; Daul, Christian

    2017-07-01

    This contribution presents a fast global adjustment scheme exploiting SURF descriptor locations for constructing large skin mosaics. Precision in pairwise image registration is well-preserved while significantly reducing the global mosaicing error.

  1. Pre-processing SAR image stream to facilitate compression for transport on bandwidth-limited-link

    Science.gov (United States)

    Rush, Bobby G.; Riley, Robert

    2015-09-29

    Pre-processing is applied to a raw VideoSAR (or similar near-video rate) product to transform the image frame sequence into a product that resembles more closely the type of product for which conventional video codecs are designed, while sufficiently maintaining utility and visual quality of the product delivered by the codec.

  2. Hierarchical Matching of Uncertain Building Models with Oblique View Airborne IR Image Sequences

    Science.gov (United States)

    Iwaszczuk, D.; Hoegner, L.; Schmitt, M.; Stilla, U.

    2012-07-01

    Thermal building textures can be used for detection of damaged and weak spots in the building structure. These textures can be extracted from airborne infrared (IR) image sequences by projecting the 3D building model into the images. However, the direct georeferencing is often not sufficiently accurate and the projected 3D model does not match the structures in the image. Thus we present a technique with the main goal to find the best fit between the existing 3D building model and the IR image sequence. For this purpose we developed a hierarchical approach consisting of two working stages. In the first stage we correct exterior orientation via line based matching. In the adjustment we consider both uncertainties: the ones of the model and the ones of the image. In the second stage we match each edge separately in its closest surrounding. Thanks to this approach a better fit between the 3D building model and the IR image was found. The originally unmodeled roof overlap was reconstructed.

  3. Current density imaging sequence for monitoring current distribution during delivery of electric pulses in irreversible electroporation.

    Science.gov (United States)

    Serša, Igor; Kranjc, Matej; Miklavčič, Damijan

    2015-01-01

    Electroporation is gaining its importance in everyday clinical practice of cancer treatment. For its success it is extremely important that coverage of the target tissue, i.e. treated tumor, with electric field is within the specified range. Therefore, an efficient tool for the electric field monitoring in the tumor during delivery of electroporation pulses is needed. The electric field can be reconstructed by the magnetic resonance electric impedance tomography method from current density distribution data. In this study, the use of current density imaging with MRI for monitoring current density distribution during delivery of irreversible electroporation pulses was demonstrated. Using a modified single-shot RARE sequence, where four 3000 V and 100 μs long pulses were included at the start, current distribution between a pair of electrodes inserted in a liver tissue sample was imaged. Two repetitions of the sequence with phases of refocusing radiofrequency pulses 90° apart were needed to acquire one current density image. For each sample in total 45 current density images were acquired to follow a standard protocol for irreversible electroporation where 90 electric pulses are delivered at 1 Hz. Acquired current density images showed that the current density in the middle of the sample increased from first to last electric pulses by 60%, i.e. from 8 kA/m2 to 13 kA/m2 and that direction of the current path did not change with repeated electric pulses significantly. The presented single-shot RARE-based current density imaging sequence was used successfully to image current distribution during delivery of short high-voltage electric pulses. The method has a potential to enable monitoring of tumor coverage by electric field during irreversible electroporation tissue ablation.

  4. A rapid Look-Locker imaging sequence for quantitative tissue oximetry

    Science.gov (United States)

    Vidya Shankar, Rohini; Kodibagkar, Vikram D.

    2015-03-01

    Tissue oximetry studies using magnetic resonance imaging are increasingly contributing to advances in the imaging and treatment of cancer. The non-invasive measurement of tissue oxygenation (pO2) may facilitate a better understanding of the pathophysiology and prognosis of diseases, particularly in the assessment of the extensive hypoxic regions associated with cancerous lesions. The availability of tumor hypoxia maps could help quantify and predict tumor response to intervention and therapy. The PISTOL (Proton Imaging of Siloxanes to map Tissue Oxygenation Levels) oximetry technique maps the T1 of administered hexamethyldisiloxane (HMDSO), an 1H NMR pO2 reporter molecule in about 3 ½ min. This allows us to subsequently monitor static and dynamic changes in the tissue pO2 (in response to intervention) at various locations due to the linear relationship between 1/T1 and pO2. In this work, an HMDSO-selective Look-Locker imaging sequence with EPI readout has been developed to enable faster PISTOL acquisitions. The new sequence incorporates the fast Look-Locker measurement method to enable T1, and hence, pO2 mapping of HMDSO in under one minute. To demonstrate the application of this pulse sequence in vivo, 50 μL of neat HMDSO was administered to the thigh muscle of a healthy rat (Fischer F344, n=4). Dynamic changes in the mean pO2 of the thigh muscle were measured using both PISTOL and the developed LL oximetry sequence in response to oxygen challenge and compared. Results demonstrate the efficacy of the new sequence in rapidly mapping the pO2 changes, leading to advances in fast quantitative 1H MR oximetry.

  5. High Dynamic Range Video

    CERN Document Server

    Myszkowski, Karol

    2008-01-01

    This book presents a complete pipeline forHDR image and video processing fromacquisition, through compression and quality evaluation, to display. At the HDR image and video acquisition stage specialized HDR sensors or multi-exposure techniques suitable for traditional cameras are discussed. Then, we present a practical solution for pixel values calibration in terms of photometric or radiometric quantities, which are required in some technically oriented applications. Also, we cover the problem of efficient image and video compression and encoding either for storage or transmission purposes, in

  6. Automatic content-based analysis of georeferenced image data: Detection of Beggiatoa mats in seafloor video mosaics from the HÅkon Mosby Mud Volcano

    Science.gov (United States)

    Jerosch, K.; Lüdtke, A.; Schlüter, M.; Ioannidis, G. T.

    2007-02-01

    The combination of new underwater technology as remotely operating vehicles (ROVs), high-resolution video imagery, and software to compute georeferenced mosaics of the seafloor provides new opportunities for marine geological or biological studies and applications in offshore industry. Even during single surveys by ROVs or towed systems large amounts of images are compiled. While these underwater techniques are now well-engineered, there is still a lack of methods for the automatic analysis of the acquired image data. During ROV dives more than 4200 georeferenced video mosaics were compiled for the HÅkon Mosby Mud Volcano (HMMV). Mud volcanoes as HMMV are considered as significant source locations for methane characterised by unique chemoautotrophic communities as Beggiatoa mats. For the detection and quantification of the spatial distribution of Beggiatoa mats an automated image analysis technique was developed, which applies watershed transformation and relaxation-based labelling of pre-segmented regions. Comparison of the data derived by visual inspection of 2840 video images with the automated image analysis revealed similarities with a precision better than 90%. We consider this as a step towards a time-efficient and accurate analysis of seafloor images for computation of geochemical budgets and identification of habitats at the seafloor.

  7. Geometric Feature-Based Facial Expression Recognition in Image Sequences Using Multi-Class AdaBoost and Support Vector Machines

    Directory of Open Access Journals (Sweden)

    Joonwhoan Lee

    2013-06-01

    Full Text Available Facial expressions are widely used in the behavioral interpretation of emotions, cognitive science, and social interactions. In this paper, we present a novel method for fully automatic facial expression recognition in facial image sequences. As the facial expression evolves over time facial landmarks are automatically tracked in consecutive video frames, using displacements based on elastic bunch graph matching displacement estimation. Feature vectors from individual landmarks, as well as pairs of landmarks tracking results are extracted, and normalized, with respect to the first frame in the sequence. The prototypical expression sequence for each class of facial expression is formed, by taking the median of the landmark tracking results from the training facial expression sequences. Multi-class AdaBoost with dynamic time warping similarity distance between the feature vector of input facial expression and prototypical facial expression, is used as a weak classifier to select the subset of discriminative feature vectors. Finally, two methods for facial expression recognition are presented, either by using multi-class AdaBoost with dynamic time warping, or by using support vector machine on the boosted feature vectors. The results on the Cohn-Kanade (CK+ facial expression database show a recognition accuracy of 95.17% and 97.35% using multi-class AdaBoost and support vector machines, respectively.

  8. Effects of imaging gradients in sequences with varying longitudinal storage time-Case of diffusion exchange imaging

    DEFF Research Database (Denmark)

    Lasic, Samo; Lundell, Henrik; Topgaard, Daniel

    2017-01-01

    Purpose: To illustrate the potential bias caused by imaging gradients in correlation MRI sequences using longitudinal magnetization storage (LS) and examine the case of filter exchange imaging (FEXI) yielding maps of the apparent exchange rate (AXR). Methods: The effects of imaging gradients...... low-pass diffusion filtering during the LS interval, which is more pronounced at lower exchange rates. For a total exchange rate constant larger than 1 s-1, the AXR bias is expected to be negligible when slices thicker than 2.5mm are used. Conclusion: In correlation experiments like FEXI, relying...... in FEXI were observed on yeast cells. To analyze the AXR bias, signal evolution was calculated by applying matrix exponential operators. Results: A sharp threshold for the slice thickness was identified, below which the AXR is increasingly underestimated. The bias can be understood in terms of an extended...

  9. Short Project-Based Learning with MATLAB Applications to Support the Learning of Video-Image Processing

    Science.gov (United States)

    Gil, Pablo

    2017-10-01

    University courses concerning Computer Vision and Image Processing are generally taught using a traditional methodology that is focused on the teacher rather than on the students. This approach is consequently not effective when teachers seek to attain cognitive objectives involving their students' critical thinking. This manuscript covers the development, implementation and assessment of a short project-based engineering course with MATLAB applications Multimedia Engineering being taken by Bachelor's degree students. The principal goal of all course lectures and hands-on laboratory activities was for the students to not only acquire image-specific technical skills but also a general knowledge of data analysis so as to locate phenomena in pixel regions of images and video frames. This would hopefully enable the students to develop skills regarding the implementation of the filters, operators, methods and techniques used for image processing and computer vision software libraries. Our teaching-learning process thus permits the accomplishment of knowledge assimilation, student motivation and skill development through the use of a continuous evaluation strategy to solve practical and real problems by means of short projects designed using MATLAB applications. Project-based learning is not new. This approach has been used in STEM learning in recent decades. But there are many types of projects. The aim of the current study is to analyse the efficacy of short projects as a learning tool when compared to long projects during which the students work with more independence. This work additionally presents the impact of different types of activities, and not only short projects, on students' overall results in this subject. Moreover, a statistical study has allowed the author to suggest a link between the students' success ratio and the type of content covered and activities completed on the course. The results described in this paper show that those students who took part

  10. An efficient video dehazing algorithm based on spectral clustering

    Science.gov (United States)

    Zhao, Fan; Yao, Zao; Song, XiaoFang; Yao, Yi

    2017-07-01

    Image and video dehazing is a popular topic in the field of computer vision and digital image processing. A fast, optimized dehazing algorithm was recently proposed that enhances contrast and reduces flickering artifacts in a dehazed video sequence by minimizing a cost function that makes transmission values spatially and temporally coherent. However, its fixed-size block partitioning leads to block effects. Further, the weak edges in a hazy image are not addressed. Hence, a video dehazing algorithm based on customized spectral clustering is proposed. To avoid block artifacts, the spectral clustering is customized to segment static scenes to ensure the same target has the same transmission value. Assuming that dehazed edge images have richer detail than before restoration, an edge cost function is added to the ransmission model. The experimental results demonstrate that the proposed method provides higher dehazing quality and lower time complexity than the previous technique.

  11. A motion correction framework for time series sequences in microscopy images.

    Science.gov (United States)

    Kumar, Ankur N; Short, Kurt W; Piston, David W

    2013-04-01

    With the advent of in vivo laser scanning fluorescence microscopy techniques, time-series and three-dimensional volumes of living tissue and vessels at micron scales can be acquired to firmly analyze vessel architecture and blood flow. Analysis of a large number of image stacks to extract architecture and track blood flow manually is cumbersome and prone to observer bias. Thus, an automated framework to accomplish these analytical tasks is imperative. The first initiative toward such a framework is to compensate for motion artifacts manifest in these microscopy images. Motion artifacts in in vivo microscopy images are caused by respiratory motion, heart beats, and other motions from the specimen. Consequently, the amount of motion present in these images can be large and hinders further analysis of these images. In this article, an algorithmic framework for the correction of time-series images is presented. The automated algorithm is comprised of a rigid and a nonrigid registration step based on shape contexts. The framework performs considerably well on time-series image sequences of the islets of Langerhans and provides for the pivotal step of motion correction in the further automatic analysis of microscopy images.

  12. Fuzzy-Based Segmentation for Variable Font-Sized Text Extraction from Images/Videos

    Directory of Open Access Journals (Sweden)

    Samabia Tehsin

    2014-01-01

    Full Text Available Textual information embedded in multimedia can provide a vital tool for indexing and retrieval. A lot of work is done in the field of text localization and detection because of its very fundamental importance. One of the biggest challenges of text detection is to deal with variation in font sizes and image resolution. This problem gets elevated due to the undersegmentation or oversegmentation of the regions in an image. The paper addresses this problem by proposing a solution using novel fuzzy-based method. This paper advocates postprocessing segmentation method that can solve the problem of variation in text sizes and image resolution. The methodology is tested on ICDAR 2011 Robust Reading Challenge dataset which amply proves the strength of the recommended method.

  13. One decade of imaging precipitation measurement by 2D-video-distrometer

    Directory of Open Access Journals (Sweden)

    M. Schönhuber

    2007-01-01

    Full Text Available The 2D-Video-Distrometer (2DVD is a ground-based point-monitoring precipitation gauge. From each particle reaching the measuring area front and side contours as well as fall velocity and precise time stamp are recorded. In 1991 the 2DVD development has been started to clarify discrepancies found when comparing weather radar data analyses with literature models. Then being manufactured in a small scale series the first 2DVD delivery took place in 1996, 10 years back from now. An overview on present 2DVD features is given, and it is presented how the instrument was continuously improved in the past ten years. Scientific merits of 2DVD measurements are explained, including drop size readings without upper limit, drop shape and orientation angle information, contours of solid and melting particles, and an independent measurement of particles' fall velocity also in mixed phase events. Plans for a next generation instrument are described, by enhanced user-friendliness the unique data type shall be opened to a wider user community.

  14. SECRETS OF SONG VIDEO

    Directory of Open Access Journals (Sweden)

    Chernyshov Alexander V.

    2014-04-01

    Full Text Available The article focuses on the origins of the song videos as TV and Internet-genre. In addition, it considers problems of screen images creation depending on the musical form and the text of a songs in connection with relevant principles of accent and phraseological video editing and filming techniques as well as with additional frames and sound elements.

  15. Sensor Fusion of a Mobile Device to Control and Acquire Videos or Images of Coffee Branches and for Georeferencing Trees.

    Science.gov (United States)

    Giraldo, Paula Jimena Ramos; Aguirre, Álvaro Guerrero; Muñoz, Carlos Mario; Prieto, Flavio Augusto; Oliveros, Carlos Eugenio

    2017-04-06

    Smartphones show potential for controlling and monitoring variables in agriculture. Their processing capacity, instrumentation, connectivity, low cost, and accessibility allow farmers (among other users in rural areas) to operate them easily with applications adjusted to their specific needs. In this investigation, the integration of inertial sensors, a GPS, and a camera are presented for the monitoring of a coffee crop. An Android-based application was developed with two operating modes: (i) Navigation: for georeferencing trees, which can be as close as 0.5 m from each other; and (ii) Acquisition: control of video acquisition, based on the movement of the mobile device over a branch, and measurement of image quality, using clarity indexes to select the most appropriate frames for application in future processes. The integration of inertial sensors in navigation mode, shows a mean relative error of ±0.15 m, and total error ±5.15 m. In acquisition mode, the system correctly identifies the beginning and end of mobile phone movement in 99% of cases, and image quality is determined by means of a sharpness factor which measures blurriness. With the developed system, it will be possible to obtain georeferenced information about coffee trees, such as their production, nutritional state, and presence of plagues or diseases.

  16. Sensor Fusion of a Mobile Device to Control and Acquire Videos or Images of Coffee Branches and for Georeferencing Trees

    Directory of Open Access Journals (Sweden)

    Paula Jimena Ramos Giraldo

    2017-04-01

    Full Text Available Smartphones show potential for controlling and monitoring variables in agriculture. Their processing capacity, instrumentation, connectivity, low cost, and accessibility allow farmers (among other users in rural areas to operate them easily with applications adjusted to their specific needs. In this investigation, the integration of inertial sensors, a GPS, and a camera are presented for the monitoring of a coffee crop. An Android-based application was developed with two operating modes: (i Navigation: for georeferencing trees, which can be as close as 0.5 m from each other; and (ii Acquisition: control of video acquisition, based on the movement of the mobile device over a branch, and measurement of image quality, using clarity indexes to select the most appropriate frames for application in future processes. The integration of inertial sensors in navigation mode, shows a mean relative error of ±0.15 m, and total error ±5.15 m. In acquisition mode, the system correctly identifies the beginning and end of mobile phone movement in 99% of cases, and image quality is determined by means of a sharpness factor which measures blurriness. With the developed system, it will be possible to obtain georeferenced information about coffee trees, such as their production, nutritional state, and presence of plagues or diseases.

  17. Video transmission on ATM networks. Ph.D. Thesis

    Science.gov (United States)

    Chen, Yun-Chung

    1993-01-01

    The broadband integrated services digital network (B-ISDN) is expected to provide high-speed and flexible multimedia applications. Multimedia includes data, graphics, image, voice, and video. Asynchronous transfer mode (ATM) is the adopted transport techniques for B-ISDN and has the potential for providing a more efficient and integrated environment for multimedia. It is believed that most broadband applications will make heavy use of visual information. The prospect of wide spread use of image and video communication has led to interest in coding algorithms for reducing bandwidth requirements and improving image quality. The major results of a study on the bridging of network transmission performance and video coding are: Using two representative video sequences, several video source models are developed. The fitness of these models are validated through the use of statistical tests and network queuing performance. A dual leaky bucket algorithm is proposed as an effective network policing function. The concept of the dual leaky bucket algorithm can be applied to a prioritized coding approach to achieve transmission efficiency. A mapping of the performance/control parameters at the network level into equivalent parameters at the video coding level is developed. Based on that, a complete set of principles for the design of video codecs for network transmission is proposed.

  18. Single-Heartbeat Electromechanical Wave Imaging with Optimal Strain Estimation Using Temporally-Unequispaced Acquisition Sequences

    Science.gov (United States)

    Provost, Jean; Thiébaut, Stéphane; Luo, Jianwen; Konofagou, Elisa E.

    2014-01-01

    Electromechanical Wave Imaging (EWI) is a non-invasive, ultrasound-based imaging method capable of mapping the electromechanical wave (EW) in vivo, i.e., the transient deformations occurring in response to the electrical activation of the heart. Achieving the optimal imaging frame rates, in terms of the elastographic signal-to-noise ratio, to capture the EW in a full-view of the heart poses a technical challenge due to the limitations of conventional imaging sequences, in which the frame rate is low and tied to the imaging parameters. To achieve higher frame rates, EWI is typically performed in multiple small regions of interest acquired over separate heartbeats, which are then combined into a single view. However, the reliance on multiple heartbeats has previously precluded the method from its application in non-periodic arrhythmias such as fibrillation. Moreover, the frame rates achieved remain sub-optimal, because they are determined by the imaging parameters rather than being optimized to image the EW. In this paper, we develop a temporally-unequispaced acquisition sequence (TUAS) for which a wide range of frame rates are achievable independently of the imaging parameters, while maintaining a full view of the heart at high beam density. TUAS is first used to determine the optimal frame rate for EWI in a paced canine heart in vivo. The feasibility of performing single-heartbeat EWI during ventricular fibrillation is then demonstrated. These results indicate that EWI can be performed optimally, within a single heartbeat, during free breathing, and implemented in real time for periodic and non-periodic cardiac events. PMID:22297208

  19. Synthesis of image sequences for Korean sign language using 3D shape model

    Science.gov (United States)

    Hong, Mun-Ho; Choi, Chang-Seok; Kim, Chang-Seok; Jeon, Joon-Hyeon

    1995-05-01

    This paper proposes a method for offering information and realizing communication to the deaf-mute. The deaf-mute communicates with another person by means of sign language, but most people are unfamiliar with it. This method enables to convert text data into the corresponding image sequences for Korean sign language (KSL). Using a general 3D shape model of the upper body leads to generating the 3D motions of KSL. It is necessary to construct the general 3D shape model considering the anatomical structure of the human body. To obtain a personal 3D shape model, this general model is to adjust to the personal base images. Image synthesis for KSL consists of deforming a personal 3D shape model and texture-mapping the personal images onto the deformed model. The 3D motions for KSL have the facial expressions and the 3D movements of the head, trunk, arms and hands and are parameterized for easily deforming the model. These motion parameters of the upper body are extracted from a skilled signer's motion for each KSL and are stored to the database. Editing the parameters according to the inputs of text data yields to generate the image sequences of 3D motions.

  20. Luminal volume reconstruction from angioscopic video images of casts from human coronary arteries

    NARCIS (Netherlands)

    J.C.H. Schuurbiers (Johan); C.J. Slager (Cornelis); P.W.J.C. Serruys (Patrick)

    1994-01-01

    textabstractIntravascular angioscopy has been hampered by its limitation in quantifying obtained images. To circumvent this problem, a lightwire was used, which projects a ring of light onto the endoluminal wall in front of the angioscope. This investigation was designed to quantify luminal

  1. Embedded electronics for a video-rate distributed aperture passive millimeter-wave imager

    Science.gov (United States)

    Curt, Petersen F.; Bonnett, James; Schuetz, Christopher A.; Martin, Richard D.

    2013-05-01

    Optical upconversion for a distributed aperture millimeter wave imaging system is highly beneficial due to its superior bandwidth and limited susceptibility to EMI. These features mean the same technology can be used to collect information across a wide spectrum, as well as in harsh environments. Some practical uses of this technology include safety of flight in degraded visual environments (DVE), imaging through smoke and fog, and even electronic warfare. Using fiber-optics in the distributed aperture poses a particularly challenging problem with respect to maintaining coherence of the information between channels. In order to capture an image, the antenna aperture must be electronically steered and focused to a particular distance. Further, the state of the phased array must be maintained, even as environmental factors such as vibration, temperature and humidity adversely affect the propagation of the signals through the optical fibers. This phenomenon cannot be avoided or mitigated, but rather must be compensated for using a closed-loop control system. In this paper, we present an implementation of embedded electronics designed specifically for this purpose. This novel architecture is efficiently small, scalable to many simultaneously operating channels and sufficiently robust. We present our results, which include integration into a 220 channel imager and phase stability measurements as the system is stressed according to MIL-STD-810F vibration profiles of an H-53E heavy-lift helicopter.

  2. QUALITY ANALYSIS OF VEHICLE-BASED SEQUENCE IMAGES RELATIVE ORIENTATION BASED ON COMPUTER VISION

    Directory of Open Access Journals (Sweden)

    L. Yan

    2012-08-01

    Full Text Available Analyzed the quality and its influence factors of relative orientation of vehicle-based sequence images by comparing with the result obtained from Position & Orientation System using Direct Geo-referencing. Studies have shown that, under normal circumstances, the image Relative Orientation based on Computer vision is more robust, and under special conditions, it is more practical for analyzing and increasing the quality of vision measurement. Besides these, the method can be borrowed by many surveying and mapping related fields, taking indoor robot mobile environment awareness and unmanned automobile for instance.

  3. Position and Attitude Estimation from a Image Sequence of a Circle

    OpenAIRE

    佐藤, 真知子; Machiko, SATO; Tokyo Institute of Polytechnics Faculty of Engineering

    1995-01-01

    A method to estimate the position and attitude of a helicopter with respect to the landing site from a image sequence of a heliport is presented. The method use the circle of the heliport marking as the visual cue. The projection of the circle on the successive image taken by on board camera will change, therefore a Kalman filter can be build for the recursive estimation. The method needs to know just there is a circle ; The size of the circle is not necessary. The result of the experiment on...

  4. The Prediction of Position and Orientation Parameters of Uav for Video Imaging

    Science.gov (United States)

    Wierzbicki, D.

    2017-08-01

    The paper presents the results of the prediction for the parameters of the position and orientation of the unmanned aerial vehicle (UAV) equipped with compact digital camera. Issue focus in this paper is to achieve optimal accuracy and reliability of the geo-referenced video frames on the basis of data from the navigation sensors mounted on UAV. In experiments two mathematical models were used for the process of the prediction: the polynomial model and the trigonometric model. The forecast values of position and orientation of UAV were compared with readings low cost GPS and INS sensors mounted on the unmanned Trimble UX-5 platform. Research experiment was conducted on the preview of navigation data from 23 measuring epochs. The forecast coordinate values and angles of the turnover and the actual readings of the sensor Trimble UX-5 were compared in this paper. Based on the results of the comparison it was determined that: the best results of co-ordinate comparison of an unmanned aerial vehicle received for the storage with, whereas worst for the coordinate Y on the base of both prediction models, obtained value of standard deviation for the coordinate XYZ from both prediction models does not cross over a admissible criterion 10 m for the term of the exactitudes of the position of a unmanned aircraft. The best results of the comparison of the angles of the turn of a unmanned aircraft received for the angle Pitch, whereas worst for the angles Heading and Roll on the base of both prediction models. Obtained value of standard deviation for the angles of turn HPR from both prediction models does not exceed a admissible exactitude 5° only for the angle Pitch, however crosses over this value for the angles Heading and Roll.

  5. Diuretic-enhanced gadolinium excretory MR urography: comparison of conventional gradient-echo sequences and echo-planar imaging.

    Science.gov (United States)

    Nolte-Ernsting, C C; Tacke, J; Adam, G B; Haage, P; Jung, P; Jakse, G; Günther, R W

    2001-01-01

    The aim of this study was to investigate the utility of different gadolinium-enhanced T1-weighted gradient-echo techniques in excretory MR urography. In 74 urologic patients, excretory MR urography was performed using various T1-weighted gradient-echo (GRE) sequences after injection of gadolinium-DTPA and low-dose furosemide. The examinations included conventional GRE sequences and echo-planar imaging (GRE EPI), both obtained with 3D data sets and 2D projection images. Breath-hold acquisition was used primarily. In 20 of 74 examinations, we compared breath-hold imaging with respiratory gating. Breath-hold imaging was significantly superior to respiratory gating for the visualization of pelvicaliceal systems, but not for the ureters. Complete MR urograms were obtained within 14-20 s using 3D GRE EPI sequences and in 20-30 s with conventional 3D GRE sequences. Ghost artefacts caused by ureteral peristalsis often occurred with conventional 3D GRE imaging and were almost completely suppressed in EPI sequences (p urography, the entire pelvicaliceal system was imaged by acquisition of a fast single-slice sequence and the conventional 2D GRE technique provided superior morphological accuracy than 2D GRE EPI projection images (p excretory MR urography especially in old or critically ill patients unable to suspend breathing for more than 20 s. Conventional GRE sequences are superior to EPI in high-resolution detail MR urograms and in projection imaging.

  6. Rain or Snow Detection in Image Sequences through use of a Histogram of Orientation of Streaks

    OpenAIRE

    Bossu, Jérémie; Hautiere, Nicolas; TAREL, Jean Philippe

    2011-01-01

    The detection of bad weather conditions is crucial for meteorological centers, specially with demand for air, sea and ground traffic management. In this article, a system based on computer vision is presented which detects the presence of rain or snow. To separate the foreground from the background in image sequences, a classical Gaussian Mixture Model is used. The foreground model serves to detect rain and snow, since these are dynamic weather phenomena. Selection rules based on photometry a...

  7. Ventilator Data Extraction with a Video Display Image Capture and Processing System.

    Science.gov (United States)

    Wax, David B; Hill, Bryan; Levin, Matthew A

    2017-06-01

    Medical hardware and software device interoperability standards are not uniform. The result of this lack of standardization is that information available on clinical devices may not be readily or freely available for import into other systems for research, decision support, or other purposes. We developed a novel system to import discrete data from an anesthesia machine ventilator by capturing images of the graphical display screen and using image processing to extract the data with off-the-shelf hardware and open-source software. We were able to successfully capture and verify live ventilator data from anesthesia machines in multiple operating rooms and store the discrete data in a relational database at a substantially lower cost than vendor-sourced solutions.

  8. Overhead-Based Image and Video Geo-Localization Framework (Open Access)

    Science.gov (United States)

    2013-09-12

    States using 100 street-level query photos. The problem is very challenging because we are trying to match two het- erogenous image sources: a street...system on the whole Switzerland area . Bansal et al. [2] were able to match query street- level facades to airborne LIDAR imagery under challenging...cover imagery. This data covers various areas in the conti- nental United States and the world, but our system tested two world regions within the

  9. Innovative Solution to Video Enhancement

    Science.gov (United States)

    2001-01-01

    Through a licensing agreement, Intergraph Government Solutions adapted a technology originally developed at NASA's Marshall Space Flight Center for enhanced video imaging by developing its Video Analyst(TM) System. Marshall's scientists developed the Video Image Stabilization and Registration (VISAR) technology to help FBI agents analyze video footage of the deadly 1996 Olympic Summer Games bombing in Atlanta, Georgia. VISAR technology enhanced nighttime videotapes made with hand-held camcorders, revealing important details about the explosion. Intergraph's Video Analyst System is a simple, effective, and affordable tool for video enhancement and analysis. The benefits associated with the Video Analyst System include support of full-resolution digital video, frame-by-frame analysis, and the ability to store analog video in digital format. Up to 12 hours of digital video can be stored and maintained for reliable footage analysis. The system also includes state-of-the-art features such as stabilization, image enhancement, and convolution to help improve the visibility of subjects in the video without altering underlying footage. Adaptable to many uses, Intergraph#s Video Analyst System meets the stringent demands of the law enforcement industry in the areas of surveillance, crime scene footage, sting operations, and dash-mounted video cameras.

  10. Evaluation of a System for High-Accuracy 3D Image-Based Registration of Endoscopic Video to C-Arm Cone-Beam CT for Image-Guided Skull Base Surgery

    Science.gov (United States)

    Mirota, Daniel J.; Uneri, Ali; Schafer, Sebastian; Nithiananthan, Sajendra; Reh, Douglas D.; Ishii, Masaru; Gallia, Gary L.; Taylor, Russell H.; Hager, Gregory D.; Siewerdsen, Jeffrey H.

    2014-01-01

    The safety of endoscopic skull base surgery can be enhanced by accurate navigation in preoperative computed tomography (CT) or, more recently, intraoperative cone-beam CT (CBCT). The ability to register real-time endoscopic video with CBCT offers an additional advantage by rendering information directly within the visual scene to account for intraoperative anatomical change. However, tracker localization error (~ 1–2 mm) limits the accuracy with which video and tomographic images can be registered. This paper reports the first implementation of image-based video-CBCT registration, conducts a detailed quantitation of the dependence of registration accuracy on system parameters, and demonstrates improvement in registration accuracy achieved by the image-based approach. Performance was evaluated as a function of parameters intrinsic to the image-based approach, including system geometry, CBCT image quality, and computational runtime. Overall system performance was evaluated in a cadaver study simulating transsphenoidal skull base tumor excision. Results demonstrated significant improvement (p < 0.001)in registration accuracy with a mean reprojection distance error of 1.28 mm for the image-based approach versus 1.82 mm for the conventional tracker-based method. Image-based registration was highly robust against CBCT image quality factors of noise and resolution, permitting integration with low-dose intraoperative CBCT. PMID:23372078

  11. Fully automated attenuation measurement and motion correction in FLIP image sequences.

    Science.gov (United States)

    van de Giessen, Martijn; van der Laan, Annelies; Hendriks, Emile A; Vidorreta, Marta; Reiber, Johan H C; Jost, Carolina R; Tanke, Hans J; Lelieveldt, Boudewijn P F

    2012-02-01

    Fluorescence loss in photobleaching (FLIP) is a method to study compartment connectivity in living cells. A FLIP sequence is obtained by alternatively bleaching a spot in a cell and acquiring an image of the complete cell. Connectivity is estimated by comparing fluorescence signal attenuation in different cell parts. The measurements of the fluorescence attenuation are hampered by the low signal to noise ratio of the FLIP sequences, by sudden sample shifts and by sample drift. This paper describes a method that estimates the attenuation by modeling photobleaching as exponentially decaying signals. Sudden motion artifacts are minimized by registering the frames of a FLIP sequence to target frames based on the estimated model and by removing frames that contain deformations. Linear motion (sample drift) is reduced by minimizing the entropy of the estimated attenuation coefficients. Experiments on 16 in vivo FLIP sequences of muscle cells in Drosophila show that the proposed method results in fluorescence attenuations similar to the manually identified gold standard, but with standard deviations of approximately 50 times smaller. As a result of this higher precision, cell compartment edges and details such as cell nuclei become clearly discernible. The main value of this method is that it uses a model of the bleaching process to correct motion and that the model based fluorescence intensity and attenuation estimates can be interpreted easily. The proposed method is fully automatic, and runs in approximately one minute per sequence, making it suitable for unsupervised batch processing of large data series.

  12. A Bayesian framework for human body pose tracking from depth image sequences.

    Science.gov (United States)

    Zhu, Youding; Fujimura, Kikuo

    2010-01-01

    This paper addresses the problem of accurate and robust tracking of 3D human body pose from depth image sequences. Recovering the large number of degrees of freedom in human body movements from a depth image sequence is challenging due to the need to resolve the depth ambiguity caused by self-occlusions and the difficulty to recover from tracking failure. Human body poses could be estimated through model fitting using dense correspondences between depth data and an articulated human model (local optimization method). Although it usually achieves a high accuracy due to dense correspondences, it may fail to recover from tracking failure. Alternately, human pose may be reconstructed by detecting and tracking human body anatomical landmarks (key-points) based on low-level depth image analysis. While this method (key-point based method) is robust and recovers from tracking failure, its pose estimation accuracy depends solely on image-based localization accuracy of key-points. To address these limitations, we present a flexible Bayesian framework for integrating pose estimation results obtained by methods based on key-points and local optimization. Experimental results are shown and performance comparison is presented to demonstrate the effectiveness of the proposed approach.

  13. A Bayesian Framework for Human Body Pose Tracking from Depth Image Sequences

    Directory of Open Access Journals (Sweden)

    Youding Zhu

    2010-05-01

    Full Text Available This paper addresses the problem of accurate and robust tracking of 3D human body pose from depth image sequences. Recovering the large number of degrees of freedom in human body movements from a depth image sequence is challenging due to the need to resolve the depth ambiguity caused by self-occlusions and the difficulty to recover from tracking failure. Human body poses could be estimated through model fitting using dense correspondences between depth data and an articulated human model (local optimization method. Although it usually achieves a high accuracy due to dense correspondences, it may fail to recover from tracking failure. Alternately, human pose may be reconstructed by detecting and tracking human body anatomical landmarks (key-points based on low-level depth image analysis. While this method (key-point based method is robust and recovers from tracking failure, its pose estimation accuracy depends solely on image-based localization accuracy of key-points. To address these limitations, we present a flexible Bayesian framework for integrating pose estimation results obtained by methods based on key-points and local optimization. Experimental results are shown and performance comparison is presented to demonstrate the effectiveness of the proposed approach.

  14. A Bayesian Framework for Human Body Pose Tracking from Depth Image Sequences

    Science.gov (United States)

    Zhu, Youding; Fujimura, Kikuo

    2010-01-01

    This paper addresses the problem of accurate and robust tracking of 3D human body pose from depth image sequences. Recovering the large number of degrees of freedom in human body movements from a depth image sequence is challenging due to the need to resolve the depth ambiguity caused by self-occlusions and the difficulty to recover from tracking failure. Human body poses could be estimated through model fitting using dense correspondences between depth data and an articulated human model (local optimization method). Although it usually achieves a high accuracy due to dense correspondences, it may fail to recover from tracking failure. Alternately, human pose may be reconstructed by detecting and tracking human body anatomical landmarks (key-points) based on low-level depth image analysis. While this method (key-point based method) is robust and recovers from tracking failure, its pose estimation accuracy depends solely on image-based localization accuracy of key-points. To address these limitations, we present a flexible Bayesian framework for integrating pose estimation results obtained by methods based on key-points and local optimization. Experimental results are shown and performance comparison is presented to demonstrate the effectiveness of the proposed approach. PMID:22399933

  15. A 3-D nonlinear recursive digital filter for video image processing

    Science.gov (United States)

    Bauer, P. H.; Qian, W.

    1991-01-01

    This paper introduces a recursive 3-D nonlinear digital filter, which is capable of performing noise suppression without degrading important image information such as edges in space or time. It also has the property of unnoticeable bandwidth reduction immediately after a scene change, which makes the filter an attractive preprocessor to many interframe compression algorithms. The filter consists of a nonlinear 2-D spatial subfilter and a 1-D temporal filter. In order to achieve the required computational speed and increase the flexibility of the filter, all of the linear shift-variant filter modules are of the IIR type.

  16. Sequence of the Essex-Lopresti lesion--a high-speed video documentation and kinematic analysis.

    Science.gov (United States)

    Wegmann, Kilian; Engel, Karsten; Burkhart, Klaus J; Ebinger, Marc; Holz, Robert; Brüggemann, Gert-Peter; Müller, Lars P

    2014-04-01

    The pathomechanics of the Essex-Lopresti lesion are not fully understood. We used human cadavers and documented the genesis of the injury with high-speed cameras. 4 formalin-fixed cadaveric specimens of human upper extremities were tested in a prototype, custom-made, drop-weight test bench. An axial high-energy impulse was applied and the development of the lesion was documented with 3 high-speed cameras. The high-speed images showed a transversal movement of the radius and ulna, which moved away from each other in the transversal plane during the impact. This resulted into a transversal rupture of the interosseous membrane, starting in its central portion, and only then did the radius migrate proximally and fracture. The lesion proceeded to the dislocation of the distal radio-ulnar joint and then to a full-blown Essex-Lopresti lesion. Our findings indicate that fracture of the radial head may be preceded by at least partial lesions of the interosseous membrane in the course of high-energy axial trauma.

  17. Dynamic Textures Modeling via Joint Video Dictionary Learning.

    Science.gov (United States)

    Wei, Xian; Li, Yuanxiang; Shen, Hao; Chen, Fang; Kleinsteuber, Martin; Wang, Zhongfeng

    2017-04-06

    Video representation is an important and challenging task in the computer vision community. In this paper, we consider the problem of modeling and classifying video sequences of dynamic scenes which could be modeled in a dynamic textures (DT) framework. At first, we assume that image frames of a moving scene can be modeled as a Markov random process. We propose a sparse coding framework, named joint video dictionary learning (JVDL), to model a video adaptively. By treating the sparse coefficients of image frames over a learned dictionary as the underlying "states", we learn an efficient and robust linear transition matrix between two adjacent frames of sparse events in time series. Hence, a dynamic scene sequence is represented by an appropriate transition matrix associated with a dictionary. In order to ensure the stability of JVDL, we impose several constraints on such transition matrix and dictionary. The developed framework is able to capture the dynamics of a moving scene by exploring both sparse properties and the temporal correlations of consecutive video frames. Moreover, such learned JVDL parameters can be used for various DT applications, such as DT synthesis and recognition. Experimental results demonstrate the strong competitiveness of the proposed JVDL approach in comparison with state-of-the-art video representation methods. Especially, it performs significantly better in dealing with DT synthesis and recognition on heavily corrupted data.

  18. Quantifying fish swimming behavior in response to acute exposure of aqueous copper using computer assisted video and digital image analysis

    Science.gov (United States)

    Calfee, Robin D.; Puglis, Holly J.; Little, Edward E.; Brumbaugh, William G.; Mebane, Christopher A.

    2016-01-01

    Behavioral responses of aquatic organisms to environmental contaminants can be precursors of other effects such as survival, growth, or reproduction. However, these responses may be subtle, and measurement can be challenging. Using juvenile white sturgeon (Acipenser transmontanus) with copper exposures, this paper illustrates techniques used for quantifying behavioral responses using computer assisted video and digital image analysis. In previous studies severe impairments in swimming behavior were observed among early life stage white sturgeon during acute and chronic exposures to copper. Sturgeon behavior was rapidly impaired and to the extent that survival in the field would be jeopardized, as fish would be swept downstream, or readily captured by predators. The objectives of this investigation were to illustrate protocols to quantify swimming activity during a series of acute copper exposures to determine time to effect during early lifestage development, and to understand the significance of these responses relative to survival of these vulnerable early lifestage fish. With mortality being on a time continuum, determining when copper first affects swimming ability helps us to understand the implications for population level effects. The techniques used are readily adaptable to experimental designs with other organisms and stressors.

  19. Developing a Video Steganography Toolkit

    OpenAIRE

    Ridgway, James; Stannett, Mike

    2014-01-01

    Although techniques for separate image and audio steganography are widely known, relatively little has been described concerning the hiding of information within video streams ("video steganography"). In this paper we review the current state of the art in this field, and describe the key issues we have encountered in developing a practical video steganography system. A supporting video is also available online at http://www.youtube.com/watch?v=YhnlHmZolRM

  20. Multiple Feature Fusion Based on Co-Training Approach and Time Regularization for Place Classification in Wearable Video

    Directory of Open Access Journals (Sweden)

    Vladislavs Dovgalecs

    2013-01-01

    Full Text Available The analysis of video acquired with a wearable camera is a challenge that multimedia community is facing with the proliferation of such sensors in various applications. In this paper, we focus on the problem of automatic visual place recognition in a weakly constrained environment, targeting the indexing of video streams by topological place recognition. We propose to combine several machine learning approaches in a time regularized framework for image-based place recognition indoors. The framework combines the power of multiple visual cues and integrates the temporal continuity information of video. We extend it with computationally efficient semisupervised method leveraging unlabeled video sequences for an improved indexing performance. The proposed approach was applied on challenging video corpora. Experiments on a public and a real-world video sequence databases show the gain brought by the different stages of the method.

  1. A New Learning Control System for Basketball Free Throws Based on Real Time Video Image Processing and Biofeedback

    Directory of Open Access Journals (Sweden)

    R. Sarang

    2018-02-01

    Full Text Available Shooting free throws plays an important role in basketball. The major problem in performing a correct free throw seems to be inappropriate training. Training is performed offline and it is often not that persistent. The aim of this paper is to consciously modify and control the free throw using biofeedback. Elbow and shoulder dynamics are calculated by an image processing technique equipped with a video image acquisition system. The proposed setup in this paper, named learning control system, is able to quantify and provide feedback of the above parameters in real time as audio signals. Therefore, it yielded to performing a correct learning and conscious control of shooting. Experimental results showed improvements in the free throw shooting style including shot pocket and locked position. The mean values of elbow and shoulder angles were controlled approximately on 89o and 26o, for shot pocket and also these angles were tuned approximately on 180o and 47o respectively for the locked position (closed to the desired pattern of the free throw based on valid FIBA references. Not only the mean values enhanced but also the standard deviations of these angles decreased meaningfully, which shows shooting style convergence and uniformity. Also, in training conditions, the average percentage of making successful free throws increased from about 64% to even 87% after using this setup and in competition conditions the average percentage of successful free throws enhanced about 20%, although using the learning control system may not be the only reason for these outcomes. The proposed system is easy to use, inexpensive, portable and real time applicable.

  2. Automated in-core image generation from video to aid visual inspection of nuclear power plant cores

    Energy Technology Data Exchange (ETDEWEB)

    Murray, Paul, E-mail: paul.murray@strath.ac.uk [Department of Electronic and Electrical Engineering, University of Strathclyde, Technology and Innovation Centre, 99 George Street, Glasgow, G1 1RD (United Kingdom); West, Graeme; Marshall, Stephen; McArthur, Stephen [Dept. Electronic and Electrical Engineering, University of Strathclyde, Royal College Building, 204 George Street, Glasgow G1 1XW (United Kingdom)

    2016-04-15

    Highlights: • A method is presented which improves visual inspection of reactor cores. • Significant time savings are made to activities on the critical outage path. • New information is extracted from existing data sources without additional overhead. • Examples from industrial case studies across the UK fleet of AGR stations. - Abstract: Inspection and monitoring of key components of nuclear power plant reactors is an essential activity for understanding the current health of the power plant and ensuring that they continue to remain safe to operate. As the power plants age, and the components degrade from their initial start-of-life conditions, the requirement for more and more detailed inspection and monitoring information increases. Deployment of new monitoring and inspection equipment on existing operational plant is complex and expensive, as the effect of introducing new sensing and imaging equipment to the existing operational functions needs to be fully understood. Where existing sources of data can be leveraged, the need for new equipment development and installation can be offset by the development of advanced data processing techniques. This paper introduces a novel technique for creating full 360° panoramic images of the inside surface of fuel channels from in-core inspection footage. Through the development of this technique, a number of technical challenges associated with the constraints of using existing equipment have been addressed. These include: the inability to calibrate the camera specifically for image stitching; dealing with additional data not relevant to the panorama construction; dealing with noisy images; and generalising the approach to work with two different capture devices deployed at seven different Advanced Gas Cooled Reactor nuclear power plants. The resulting data processing system is currently under formal assessment with a view to replacing the existing manual assembly of in-core defect montages. Deployment of the

  3. BOLD imaging in the mouse brain using a turboCRAZED sequence at high magnetic fields.

    Science.gov (United States)

    Schneider, Johannes T; Faber, Cornelius

    2008-10-01

    Functional MRI (fMRI) based on the detection of intermolecular double-quantum coherences (iDQC) has previously been shown to provide pronounced activation signal. For fMRI in small animals at very high magnetic fields, the essential fast gradient echo-based readout methods become problematic. Here, rapid intermolecular double-quantum coherence (iDQC) imaging was implemented, combining the iDQC preparation sequence with a Turbo spin echo-like readout. Four-step phase cycling and a novel intensity-ordered k-space encoding scheme with separate acquisition of odd and even echoes were essential to optimize signal to noise ratio efficiency. Compared with a single echo readout of iDQC signal, acceleration of factor 16 was achieved in phantoms using the novel method at 17.6 Tesla. In vivo, echo trains consisting of 32 echoes were possible and images of the mouse brain were obtained in 30 s. The blood oxygen level dependent (BOLD) effect in the mouse brain upon change of breathing gas was observed as average signal change of (6.3 +/- 1.1)% in iDQC images. Signal changes in conventional multi spin echo images were (4.4 +/- 2.3)% and (8.3 +/- 3.8)% with gradient echo methods. Combination of T(2)*-weighting with the fast iDQC sequence may yield higher signal changes than with either method alone, and establish fast iDQC imaging a robust tool for high field fMRI in small animals. (c) 2008 Wiley-Liss, Inc.

  4. Managing complex processing of medical image sequences by program supervision techniques

    Science.gov (United States)

    Crubezy, Monica; Aubry, Florent; Moisan, Sabine; Chameroy, Virginie; Thonnat, Monique; Di Paola, Robert

    1997-05-01

    Our objective is to offer clinicians wider access to evolving medical image processing (MIP) techniques, crucial to improve assessment and quantification of physiological processes, but difficult to handle for non-specialists in MIP. Based on artificial intelligence techniques, our approach consists in the development of a knowledge-based program supervision system, automating the management of MIP libraries. It comprises a library of programs, a knowledge base capturing the expertise about programs and data and a supervision engine. It selects, organizes and executes the appropriate MIP programs given a goal to achieve and a data set, with dynamic feedback based on the results obtained. It also advises users in the development of new procedures chaining MIP programs.. We have experimented the approach for an application of factor analysis of medical image sequences as a means of predicting the response of osteosarcoma to chemotherapy, with both MRI and NM dynamic image sequences. As a result our program supervision system frees clinical end-users from performing tasks outside their competence, permitting them to concentrate on clinical issues. Therefore our approach enables a better exploitation of possibilities offered by MIP and higher quality results, both in terms of robustness and reliability.

  5. Power Distortion Optimization for Uncoded Linear Transformed Transmission of Images and Videos.

    Science.gov (United States)

    Xiong, Ruiqin; Zhang, Jian; Wu, Feng; Xu, Jizheng; Gao, Wen

    2017-01-01

    Recently, there is a resurgence of interest in uncoded transmission for wireless visual communication. While conventional coded systems suffer from cliff effect as the channel condition varies dynamically, uncoded linear-transformed transmission (ULT) provides elegant quality degradation for wide channel SNR range. ULT skips non-linear operations, such as quantization and entropy coding. Instead, it utilizes linear decorrelation transform and linear scaling power allocation to achieve optimized transmission. This paper presents a theoretical analysis for power-distortion optimization of ULT. In addition to the observation in our previous work that a decorrelation transform can bring significant performance gain, this paper reveals that exploiting the energy diversity in transformed signal is the key to achieve the full potential of decorrelation transform. In particular, we investigated the efficiency of ULT with exact or inexact signal statistics, highlighting the impact of signal energy modeling accuracy. Based on that, we further proposed two practical energy modeling schemes for ULT of visual signals. Experimental results show that the proposed schemes improve the quality of reconstructed images by 3~5 dB, while reducing the signal modeling overhead from hundreds or thousands of meta data to only a few meta data. The perceptual quality of reconstruction is significantly improved.

  6. Power-Distortion Optimization for Uncoded Linear-Transformed Transmission of Images and Videos.

    Science.gov (United States)

    Xiong, Ruiqin; Zhang, Jian; Wu, Feng; Xu, Jizheng; Gao, Wen

    2016-10-26

    Recently there is a resurgence of interest in uncoded transmission for wireless visual communication. While conventional coded systems suffer from cliff effect as the channel condition varies dynamically, uncoded linear-transformed transmission (ULT) provides elegant quality degradation for wide channel SNR range. ULT skips non-linear operations such as quantization and entropy coding. Instead, it utilizes linear decorrelation transform and linear scaling power allocation to achieve optimized transmission. This paper presents a theoretical analysis for power-distortion optimization of ULT. In addition to the observation in our previous work that a decorrelation transform can bring significant performance gain, this work reveals that exploiting the energy diversity in transformed signal is the key to achieve the full potential of decorrelation transform. In particular, we investigated the efficiency of ULT with exact or inexact signal statistics, highlighting the impact of signal energy modeling accuracy. Based on that, we further proposed two practical energy modeling schemes for ULT of visual signals. Experimental results show that the proposed schemes improve the quality of reconstructed images by 3 5dB, while reducing the signal modeling overhead from hundreds or thousands of meta data to only a few meta data. The perceptual quality of reconstruction is significantly improved.

  7. Image/video understanding systems based on network-symbolic models and active vision

    Science.gov (United States)

    Kuvich, Gary

    2004-07-01

    Vision is a part of information system that converts visual information into knowledge structures. These structures drive the vision process, resolving ambiguity and uncertainty via feedback, and provide image understanding, which is an interpretation of visual information in terms of these knowledge models. It is hard to split the entire system apart, and vision mechanisms cannot be completely understood separately from informational processes related to knowledge and intelligence. Brain reduces informational and computational complexities, using implicit symbolic coding of features, hierarchical compression, and selective processing of visual information. Vision is a component of situation awareness, motion and planning systems. Foveal vision provides semantic analysis, recognizing objects in the scene. Peripheral vision guides fovea to salient objects and provides scene context. Biologically inspired Network-Symbolic representation, in which both systematic structural/logical methods and neural/statistical methods are parts of a single mechanism, converts visual information into relational Network-Symbolic structures, avoiding precise artificial computations of 3-D models. Network-Symbolic transformations derive more abstract structures that allows for invariant recognition of an object as exemplar of a class and for a reliable identification even if the object is occluded. Systems with such smart vision will be able to navigate in real environment and understand real-world situations.

  8. Active vision and image/video understanding systems for UGV based on network-symbolic models

    Science.gov (United States)

    Kuvich, Gary

    2004-09-01

    Vision evolved as a sensory system for reaching, grasping and other motion activities. In advanced creatures, it has become a vital component of situation awareness, navigation and planning systems. Vision is part of a larger information system that converts visual information into knowledge structures. These structures drive the vision process, resolving ambiguity and uncertainty via feedback, and provide image understanding, that is an interpretation of visual information in terms of such knowledge models. It is hard to split such a system apart. Biologically inspired Network-Symbolic representation, where both systematic structural/logical methods and neural/statistical methods are parts of a single mechanism, is the most feasible for natural processing of visual information. It converts visual information into relational Network-Symbolic models, avoiding artificial precise computations of 3-dimensional models. Logic of visual scenes can be captured in such models and used for disambiguation of visual information. Network-Symbolic transformations derive abstract structures, which allows for invariant recognition of an object as exemplar of a class. Active vision helps create unambiguous network-symbolic models. This approach is consistent with NIST RCS. The UGV, equipped with such smart vision, will be able to plan path and navigate in a real environment, perceive and understand complex real-world situations and act accordingly.

  9. Temporal statistics of natural image sequences generated by movements with insect flight characteristics.

    Directory of Open Access Journals (Sweden)

    Alexander Schwegmann

    Full Text Available Many flying insects, such as flies, wasps and bees, pursue a saccadic flight and gaze strategy. This behavioral strategy is thought to separate the translational and rotational components of self-motion and, thereby, to reduce the computational efforts to extract information about the environment from the retinal image flow. Because of the distinguishing dynamic features of this active flight and gaze strategy of insects, the present study analyzes systematically the spatiotemporal statistics of image sequences generated during saccades and intersaccadic intervals in cluttered natural environments. We show that, in general, rotational movements with saccade-like dynamics elicit fluctuations and overall changes in brightness, contrast and spatial frequency of up to two orders of magnitude larger than translational movements at velocities that are characteristic of insects. Distinct changes in image parameters during translations are only caused by nearby objects. Image analysis based on larger patches in the visual field reveals smaller fluctuations in brightness and spatial frequency composition compared to small patches. The temporal structure and extent of these changes in image parameters define the temporal constraints imposed on signal processing performed by the insect visual system under behavioral conditions in natural environments.

  10. Video microblogging

    DEFF Research Database (Denmark)

    Bornoe, Nis; Barkhuus, Louise

    2010-01-01

    Microblogging is a recently popular phenomenon and with the increasing trend for video cameras to be built into mobile phones, a new type of microblogging has entered the arena of electronic communication: video microblogging. In this study we examine video microblogging, which is the broadcasting...... of short videos. A series of semi-structured interviews offers an understanding of why and how video microblogging is used and what the users post and broadcast....

  11. Image-guided depth propagation for 2-D-to-3-D video conversion using superpixel matching and adaptive autoregressive model

    Science.gov (United States)

    Cai, Jiji; Jung, Cheolkon

    2017-09-01

    We propose image-guided depth propagation for two-dimensional (2-D)-to-three-dimensional (3-D) video conversion using superpixel matching and the adaptive autoregressive (AR) model. We adopt key frame-based depth propagation that propagates the depth map in the key frame to nonkey frames. Moreover, we use the adaptive AR model for depth refinement to penalize depth-color inconsistency. First, we perform superpixel matching to estimate motion vectors at the superpixel level instead of block matching based on the fixed block size. Then, we conduct depth compensation based on motion vectors to generate the depth map in the nonkey frame. However, the size of two superpixels is not exactly the same due to the segment-based matching, which causes matching errors in the compensated depth map. Thus, we introduce an adaptive image-guided AR model to minimize matching errors and produce the final depth map by minimizing AR prediction errors. Finally, we employ depth-image-based rendering to generate stereoscopic views from 2-D videos and their depth maps. Experimental results demonstrate that the proposed method successfully performs depth propagation and produces high-quality depth maps for 2-D-to-3-D video conversion.

  12. Single molecule dynamics in a virtual cell: a three-dimensional model that produces simulated fluorescence video-imaging data.

    Science.gov (United States)

    Mashanov, Gregory I

    2014-09-06

    The analysis of single molecule imaging experiments is complicated by the stochastic nature of single molecule events, by instrument noise and by the limited information which can be gathered about any individual molecule observed. Consequently, it is important to cross check experimental results using a model simulating single molecule dynamics (e.g. movements and binding events) in a virtual cell-like environment. The output of such a model should match the real data format allowing researchers to compare simulated results with the real experiments. The proposed model exploits the advantages of 'object-oriented' computing. First of all, the ability to create and manipulate a number of classes, each containing an arbitrary number of single molecule objects. These classes may include objects moving within the 'cytoplasm'; objects moving at the 'plasma membrane'; and static objects located inside the 'body'. The objects of a given class can interact with each other and/or with the objects of other classes according to their physical and chemical properties. Each model run generates a sequence of images, each containing summed images of all fluorescent objects emitting light under given illumination conditions with realistic levels of noise and emission fluctuations. The model accurately reproduces reported single molecule experiments and predicts the outcome of future experiments.

  13. Scalable gastroscopic video summarization via similar-inhibition dictionary selection.

    Science.gov (United States)

    Wang, Shuai; Cong, Yang; Cao, Jun; Yang, Yunsheng; Tang, Yandong; Zhao, Huaici; Yu, Haibin

    2016-01-01

    This paper aims at developing an automated gastroscopic video summarization algorithm to assist clinicians to more effectively go through the abnormal contents of the video. To select the most representative frames from the original video sequence, we formulate the problem of gastroscopic video summarization as a dictionary selection issue. Different from the traditional dictionary selection methods, which take into account only the number and reconstruction ability of selected key frames, our model introduces the similar-inhibition constraint to reinforce the diversity of selected key frames. We calculate the attention cost by merging both gaze and content change into a prior cue to help select the frames with more high-level semantic information. Moreover, we adopt an image quality evaluation process to eliminate the interference of the poor quality images and a segmentation process to reduce the computational complexity. For experiments, we build a new gastroscopic video dataset captured from 30 volunteers with more than 400k images and compare our method with the state-of-the-arts using the content consistency, index consistency and content-index consistency with the ground truth. Compared with all competitors, our method obtains the best results in 23 of 30 videos evaluated based on content consistency, 24 of 30 videos evaluated based on index consistency and all videos evaluated based on content-index consistency. For gastroscopic video summarization, we propose an automated annotation method via similar-inhibition dictionary selection. Our model can achieve better performance compared with other state-of-the-art models and supplies more suitable key frames for diagnosis. The developed algorithm can be automatically adapted to various real applications, such as the training of young clinicians, computer-aided diagnosis or medical report generation. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. [Video documentation in forensic practice].

    Science.gov (United States)

    Schyma, C; Schyma, P

    1995-01-01

    The authors report in part 1 about their experiences with the Canon Ex1 Hi camcorder and the possibilities of documentation with the modern video technique. Application examples in legal medicine and criminalistics are described autopsy, scene, reconstruction of crimes etc. The online video documentation of microscopic sessions makes the discussion of findings easier. The use of video films for instruction produces a good resonance. The use of the video documentation can be extended by digitizing (Part 2). Two frame grabbers are presented, with which we obtained good results in digitizing of images captured from video. The best quality of images is achieved by online use of an image analysis chain. Corel 5.0 and PicEd Cora 4.0 allow complete image processings and analysis. The digital image processing influences the objectivity of the documentation. The applicabilities of image libraries are discussed.

  15. Update on MRI Pulse Sequences for the Knee: Imaging of Cartilage, Meniscus, Tendon, and Hardware.

    Science.gov (United States)

    Ariyachaipanich, Aticha; Bae, Won C; Statum, Sheronda; Chung, Christine B

    2017-04-01

    Magnetic resonance imaging (MRI) is widely used in the clinical setting as well as for research applications. Since its inception, technical development has broadly progressed as a response to challenges in both the clinical and research settings. Higher magnetic field strength and advances in hardware and software have revolutionized the diagnostic potential of MRI and moved well beyond diagnosis to characterization of tissue metabolism, biochemistry, disease pathogenesis, and material property, to name a few. This article focuses on state-of-the-art clinical and cutting-edge novel pulse sequences applied to knee MRI. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  16. Novel permutation-diffusion image encryption algorithm with chaotic dynamic S-box and DNA sequence operation

    Science.gov (United States)

    Tian, Ye; Lu, Zhimao

    2017-08-01

    The development of the computer network makes image files transportation via network become more and more convenient. This paper is concerned with the image encryption algorithm design based on the chaotic S-box mechanism. This paper proposes an Image Encryption algorithm involving both chaotic dynamic S-boxes and DNA sequence operation(IESDNA). The contribution of this paper is three folded: Firstly, we design an external 256-bit key to get large key space; secondly, we design a chaotic system to scramble image pixels; thirdly, DNA sequence operations are adopted to diffuse the scrambled image pixels. Experimental results show that our proposed image encryption algorithm can meet multiple cryptographic criteria and obtain good image encryption effect.

  17. Free-viewpoint video synthesis from mixed resolution multi-view images and low resolution depth maps

    Science.gov (United States)

    Emori, Takaaki; Tehrani, Mehrdad P.; Takahashi, Keita; Fujii, Toshiaki

    2015-03-01

    Streaming application of multi-view and free-viewpoint video is potentially attractive but due to the limitation of bandwidth, transmitting all multi-view video in high resolution may not be feasible. Our goal is to propose a new streaming data format that can be adapted to the limited bandwidth and capable of free-viewpoint video streaming using multi-view video plus depth (MVD). Given a requested free-viewpoint, we use the two closest views and corresponding depth maps to perform free-viewpoint video synthesis. We propose a new data format that consists of all views and corresponding depth maps in a lowered resolution, and the two closest views to the requested viewpoint in the high resolution. When the requested viewpoint changes, the two closest viewpoints will change, but one or both of views are transmitted only in the low resolution during the delay time. Therefore, the resolution compensation is required. In this paper, we investigated several cases where one or both of the views are transmitted only in the low resolution. We proposed adequate view synthesis method for multi resolution multi-view video plus depth. Experimental results show that our framework achieves view synthesis quality close to high resolution multi-view video plus depth.

  18. Bubbles: a unifying framework for low-level statistical properties of natural image sequences.

    Science.gov (United States)

    Hyvärinen, Aapo; Hurri, Jarmo; Väyrynen, Jaakko

    2003-07-01

    Recently, different models of the statistical structure of natural images have been proposed. These models predict properties of biological visual systems and can be used as priors in Bayesian inference. The fundamental model is independent component analysis, which can be estimated by maximization of the sparsenesses of linear filter outputs. This leads to the emergence of principal simple cell properties. Alternatively, simple cell properties are obtained by maximizing the temporal coherence in natural image sequences. Taking account of the basic dependencies of linear filter outputs permit modeling of complex cells and topographic organization as well. We propose a unifying framework for these statistical properties, based on the concept of spatiotemporal activity "bubbles."A bubble means here an activation of simple cells (linear filters) that is contiguous both in space (the cortical surface) and in time.

  19. Temporal and spatiotemporal coherence in simple-cell responses: a generative model of natural image sequences.

    Science.gov (United States)

    Hurri, Jarmo; Hyvärinen, Aapo

    2003-08-01

    We present a two-layer dynamic generative model of the statistical structure of natural image sequences. The second layer of the model is a linear mapping from simple-cell outputs to pixel values, as in most work on natural image statistics. The first layer models the dependencies of the activity levels (amplitudes or variances) of the simple cells, using a multivariate autoregressive model. The second layer shows the emergence of basis vectors that are localized, oriented and have different scales, just like in previous work. But in our new model, the first layer learns connections between the simple cells that are similar to complex cell pooling: connections are strong among cells with similar preferred location, frequency and orientation. In contrast to previous work in which one of the layers needed to be fixed in advance, the dynamic model enables us to estimate both of the layers simultaneously from natural data.

  20. Diuretic-enhanced gadolinium excretory MR urography: comparison of conventional gradient-echo sequences and echo-planar imaging

    Energy Technology Data Exchange (ETDEWEB)

    Nolte-Ernsting, C.C.A.; Tacke, J.; Adam, G.B.; Haage, P.; Guenther, R.W. [Univ. of Technology, Aachen (Germany). Dept. of Diagnostic Radiology; Jung, P.; Jakse, G. [Univ. of Technology, Aachen (Germany). Dept. of Urology

    2001-01-01

    The aim of this study was to investigate the utility of different gadolinium-enhanced T1-weighted gradient-echo techniques in excretory MR urography. In 74 urologic patients, excretory MR urography was performed using various T1-weighted gradient-echo (GRE) sequences after injection of gadolinium-DTPA and low-dose furosemide. The examinations included conventional GRE sequences and echo-planar imaging (GRE EPI), both obtained with 3D data sets and 2D projection images. Breath-hold acquisition was used primarily. In 20 of 74 examinations, we compared breath-hold imaging with respiratory gating. Breath-hold imaging was significantly superior to respiratory gating for the visualization of pelvicaliceal systems, but not for the ureters. Complete MR urograms were obtained within 14-20 s using 3D GRE EPI sequences and in 20-30 s with conventional 3D GRE sequences. Ghost artefacts caused by ureteral peristalsis often occurred with conventional 3D GRE imaging and were almost completely suppressed in EPI sequences (p < 0.0001). Susceptibility effects were more pronounced on GRE EPI MR urograms and calculi measured 0.8-21.7% greater in diameter compared with conventional GRE sequences. Increased spatial resolution degraded the image quality only in GRE-EPI urograms. (orig.)