Imaging of the digital arteries: Digital subtraction angiography versus conventional angiography

International Nuclear Information System (INIS)

Menanteau, B.P.; Treutenaere, J.M.; Marcus, C.; Ladam, V.; Gausserand, F.

1986-01-01

The authors report their experience with the use of digital subtraction angiography (DSA) and conventional angiography of the hand. Of the 95 patients in the study group, 80 underwent conventional angiography and 15 underwent DSA. They analyzed the studies with regard to the type and amount of contrast agent used, the number of radiographs needed, and the diagnostic quality of the images. Conventional angiography often requires general anesthesia, magnification, and pharmaco-angiographic techniques to improve the image-based diagnosis. In comparison with conventional angiography, intraarterial DSA is characterized by improved contrast sensitivity and inferior spatial resolution. However, DSA provides images as acceptable as those of conventional angiography. Smaller catheters can be used, and the examination is performed under local anesthesia. The authors conclude that intraarterial DSA is now the technique of choice for examining patients with chronic ischemia of the hand

A hand-held beta imaging probe for FDG.

Science.gov (United States)

Singh, Bipin; Stack, Brendan C; Thacker, Samta; Gaysinskiy, Valeriy; Bartel, Twyla; Lowe, Val; Cool, Steven; Entine, Gerald; Nagarkar, Vivek

2013-04-01

Advances in radiopharmaceuticals and clinical understanding have escalated the use of intraoperative gamma probes in surgery. However, most probes on the market are non-imaging gamma probes that suffer from the lack of ancillary information of the surveyed tissue area. We have developed a novel, hand-held digital Imaging Beta Probe™ (IBP™) to be used in surgery in conjunction with beta-emitting radiopharmaceuticals such as (18)FDG, (131)I and (32)P for real-time imaging of a surveyed area with higher spatial resolution and sensitivity and greater convenience than existing instruments. We describe the design and validation of a hand-held beta probe intended to be used as a visual mapping device to locate and confirm excision of (18)FDG-avid primary tumors and metastases in an animal model. We have demonstrated a device which can generate beta images from (18)FDG avid lesions in an animal model. It is feasible to image beta irradiation in animal models of cancer given (18)FDG. This technology may be applied to clinical mapping of tumors and/or their metastases in the operating room. Visual image depiction of malignancy may aid the surgeon in localization and excision of lesions of interest.

Digital cine-imaging

International Nuclear Information System (INIS)

Masuda, Kazuhiro

1992-01-01

Digitization of fluoroscopic images has been developed for the digital cine imaging system as a result of the computer technology, television technology, and popularization of interventional radiology. Present digital cine imaging system is able to offer images similar to cine film because of the higher operatability and better image quality with the development of interventional radiology. As a result, its higher usefulness for catheter diagnosis examination except for interventional radiology was reported, and the possibility of having filmless cine is close to becoming a reality. However several problems have been pointed out, such as spatial resolution, time resolution, storage and exchangeability of data, disconsolidated viewing functions, etc. Anyhow, digital cine imaging system has some unresolved points and lots the needs to be discussed. The tendency of digitization is the passage of the time and we have to promote a study for more useful digital cine imaging system in team medical treatment which centers on the patients. (author)

Bone age assessment in Hispanic children: digital hand atlas compared with the Greulich and Pyle (G&P) atlas

Science.gov (United States)

Fernandez, James Reza; Zhang, Aifeng; Vachon, Linda; Tsao, Sinchai

2008-03-01

Bone age assessment is most commonly performed with the use of the Greulich and Pyle (G&P) book atlas, which was developed in the 1950s. The population of theUnited States is not as homogenous as the Caucasian population in the Greulich and Pyle in the 1950s, especially in the Los Angeles, California area. A digital hand atlas (DHA) based on 1,390 hand images of children of different racial backgrounds (Caucasian, African American, Hispanic, and Asian) aged 0-18 years was collected from Children's Hospital Los Angeles. Statistical analysis discovered significant discrepancies exist between Hispanic and the G&P atlas standard. To validate the usage of DHA as a clinical standard, diagnostic radiologists performed reads on Hispanic pediatric hand and wrist computed radiography images using either the G&P pediatric radiographic atlas or the Children's Hospital Los Angeles Digital Hand Atlas (DHA) as reference. The order in which the atlas is used (G&P followed by DHA or vice versa) for each image was prepared before actual reading begins. Statistical analysis of the results was then performed to determine if a discrepancy exists between the two readings.

Digital image analysis of X-ray television with an image digitizer

International Nuclear Information System (INIS)

Mochizuki, Yasuo; Akaike, Hisahiko; Ogawa, Hitoshi; Kyuma, Yukishige

1995-01-01

When video signals of X-ray fluoroscopy were transformed from analog-to-digital ones with an image digitizer, their digital characteristic curves, pre-sampling MTF's and digital Wiener spectral could be measured. This method was advant ageous in that it was able to carry out data sampling because the pixel values inputted could be verified on a CRT. The system of image analysis by this method is inexpensive and effective in evaluating the image quality of digital system. Also, it is expected that this method can be used as a tool for learning the measurement techniques and physical characteristics of digital image quality effectively. (author)

Digital knowledge in the coat pocket - hand-held personal digital assistants in radiology

International Nuclear Information System (INIS)

Niehues, S.M.; Froehlich, M.; Felix, R.; Lemke, A.J.

2004-01-01

The personal digital assistant (PDA) enables the independent access to large data in a pocket-sized format. The applications for hand-held computers are growing steadily and can support almost any kind of problem. An overview of the available hardware and software is provided and evaluated. Furthermore, the use of the PDA in the clinical daily routine is described. In view of the numerous software programs available in radiology, the range of software solutions for radiologists is presented. Despite the high acquisition cost, the PDA has already become the digital assistant for the radiologist. After a short time of getting used to the PDA, nobody wants to miss it at work or at home. New technical features and available software programs will continuously increase the integration of the PDA into the medical workflow in the near future. (orig.)

Digital radiology and digitally formatted image management systems

International Nuclear Information System (INIS)

Cox, G.G.; Dwyer, S.J. III; Templeton, A.W.

1987-01-01

The number of diagnostic examinations performed with digitally formatted imaging equipment is increasing. Digital general-purpose and fluoroscopic radiology systems are being clinically evaluated. Digitizing conventional x-ray films, such as mammograms, frequently improves the diagnostic quality of the images. The digitizing process with laser has also afforded the opportunity to document required spatial resolution for digital imaging and network systems. The use of digitally formatted image instrumentation imposes new requirements on the acquisition, display and manipulation, transmission, hard copy image recording, and archiving of diagnostic data. Networking of digitally formatted image data offers many advantages for managing digital information. This paper identifies and describes digital radiographic systems. Parameters required for designing and implementing a digital image management system are outlined. Spatial and contrast resolution requirements are identified. The key parameters include the amount of image data generated each working day, the retrieval rate of the generated data, the display hardware and software needed for interactive diagnosis display stations, the requirements for analog hard copy generation, and on-line and long-term archiving requirements. These image management systems are often called PACS (Picture Archiving and Communication Systems)

Digital fringe projection for hand surface coordinate variation analysis caused by osteoarthritis

Science.gov (United States)

Nor Haimi, Wan Mokhdzani Wan; Hau Tan, Cheek; Retnasamy, Vithyacharan; Vairavan, Rajendaran; Sauli, Zaliman; Roshidah Yusof, Nor; Hambali, Nor Azura Malini Ahmad; Aziz, Muhammad Hafiz Ab; Bakhit, Ahmad Syahir Ahmad

2017-11-01

Hand osteoarthritis is one of the most common forms of arthritis which impact millions of people worldwide. The disabling problem occurs when the protective cartilage on the boundaries of bones wear off over time. Currently, in order to identify hand osteoarthritis, special instruments namely X-ray scanning and MRI are used for the detection but it also has its limitations such as radiation exposure and can be quite costly. In this work, an optical metrology system based on digital fringe projection which comprises of an LCD projector, CCD camera and a personal computer has been developed to anticipate abnormal growth or deformation on the joints of the hand which are common symptoms of osteoarthritis. The main concept of this optical metrology system is to apply structured light as imaging source for surface change detection. The imaging source utilizes fringe patterns generated by C++ programming and is shifted by 3 phase shifts based on the 3 steps 2 shifts method. Phase wrapping technique and analysis were applied in order to detect the deformation of live subjects. The result has demonstrated a successful method of hand deformation detection based on the pixel tracking differences of a normal and deformed state.

DHM (Digital Holography Microscope) for imaging cells

International Nuclear Information System (INIS)

Emery, Yves; Cuche, Etienne; Colomb, Tristan; Depeursinge, Christian; Rappaz, Benjamin; Marquet, Pierre; Magistretti, Pierre

2007-01-01

Light interaction with a sample modifies both intensity and phase of the illuminating wave. Any available supports for image recording are only sensitive to intensity, but Denis Gabor [P. Marquet, B. Rappaz, P. Magistretti, et. al. Digital Holography for quantitative phase-contrast imaging, Optics Letters, 30, 5, pp 291-93 (2005)] invented in 1948 a way to encode the phase as an intensity variation: the h ologram . Digital Holographic Microscopy (DHM) [D. Gabor, A new microscopic principle, Nature, 1948] implements digitally this powerful hologram. Characterization of various pollen grains and of morphology changes of neurones associated with hypotonic shock demonstrates the potential of DHM for imaging cells

Imaging of hand injuries. Anatomic and radiodiagnostic considerations

International Nuclear Information System (INIS)

Schmitt, Rainer

2011-01-01

Imaging recommendations for assessing injuries of the forearm, wrist, metacarpus and the digits are given with respect to anatomic considerations. Furthermore, dedicated algorithms of advanced imaging are introduced with radiography as the primary diagnostic tool. High-resolution CT is used for detecting and staging the complex fractures of the radius and the wrist, whereas contrast-enhanced MRI serves for depicting the injured soft tissues. At the wrist, tears of the intrinsic ligaments and the TFCC are assessed with high accuracy when applying MR arthrography or CT arthrography. Dedicated radiologic tools as well as comprehensive reports are suggested in the management of the various hand injuries. (orig.)

Digital cardiovascular imaging

International Nuclear Information System (INIS)

Myerowitz, P.D.; Mistretta, C.A.; Shaw, C.-G.; Van Lysel, M.S.; Swanson, D.K.; Lasser, T.A.; Dhanani, S.P.; Zarnstorff, W.C.; Vander Ark, C.R.; Dobbins, J.T.; Peppler, W.W.; Crummy, A.B.

1982-01-01

The authors have previously reported on real time digital fluoroscopic subtraction techniques developed in the laboratory during the past 10 years. This paper outlines basic apparatus configuration and imaging modes used for preliminary studies involving visualization of the canine and human heart. All of the techniques involve the use of real time digital subtraction processing of data from an image intensified television fluoroscopy system. Based on the configuration of the digital processing equipment a number of different imaging modalities are possible. A brief description of the apparatus and these imaging modes is given. (Auth.)

Improving digital image watermarking by means of optimal channel selection

NARCIS (Netherlands)

Huynh-The, Thien; Banos Legran, Oresti; Lee, Sungyoung; Yoon, Yongik; Le-Tien, Thuong

2016-01-01

Supporting safe and resilient authentication and integrity of digital images is of critical importance in a time of enormous creation and sharing of these contents. This paper presents an improved digital image watermarking model based on a coefficient quantization technique that intelligently

Digital Imaging. Chapter 16

Energy Technology Data Exchange (ETDEWEB)

Clunie, D. [CoreLab Partners, Princeton (United States)

2014-09-15

The original means of recording X ray images was a photographic plate. Nowadays, all medical imaging modalities provide for digital acquisition, though globally, the use of radiographic film is still widespread. Many modalities are fundamentally digital in that they require image reconstruction from quantified digital signals, such as computed tomography (CT) and magnetic resonance imaging (MRI)

A digital library of radiology images.

Science.gov (United States)

Kahn, Charles E

2006-01-01

A web-based virtual library of peer-reviewed radiological images was created for use in education and clinical decision support. Images were obtained from open-access content of five online radiology journals and one e-learning web site. Figure captions were indexed by Medical Subject Heading (MeSH) codes, imaging modality, and patient age and sex. This digital library provides a new, valuable online resource.

Hands-free image capture, data tagging and transfer using Google Glass: a pilot study for improved wound care management.

Directory of Open Access Journals (Sweden)

Gabriel Aldaz

Full Text Available Chronic wounds, including pressure ulcers, compromise the health of 6.5 million Americans and pose an annual estimated burden of $25 billion to the U.S. health care system. When treating chronic wounds, clinicians must use meticulous documentation to determine wound severity and to monitor healing progress over time. Yet, current wound documentation practices using digital photography are often cumbersome and labor intensive. The process of transferring photos into Electronic Medical Records (EMRs requires many steps and can take several days. Newer smartphone and tablet-based solutions, such as Epic Haiku, have reduced EMR upload time. However, issues still exist involving patient positioning, image-capture technique, and patient identification. In this paper, we present the development and assessment of the SnapCap System for chronic wound photography. Through leveraging the sensor capabilities of Google Glass, SnapCap enables hands-free digital image capture, and the tagging and transfer of images to a patient's EMR. In a pilot study with wound care nurses at Stanford Hospital (n=16, we (i examined feature preferences for hands-free digital image capture and documentation, and (ii compared SnapCap to the state of the art in digital wound care photography, the Epic Haiku application. We used the Wilcoxon Signed-ranks test to evaluate differences in mean ranks between preference options. Preferred hands-free navigation features include barcode scanning for patient identification, Z(15 = -3.873, p < 0.001, r = 0.71, and double-blinking to take photographs, Z(13 = -3.606, p < 0.001, r = 0.71. In the comparison between SnapCap and Epic Haiku, the SnapCap System was preferred for sterile image-capture technique, Z(16 = -3.873, p < 0.001, r = 0.68. Responses were divided with respect to image quality and overall ease of use. The study's results have contributed to the future implementation of new features aimed at enhancing mobile hands-free digital

Hands-Free Image Capture, Data Tagging and Transfer Using Google Glass: A Pilot Study for Improved Wound Care Management

Science.gov (United States)

Aldaz, Gabriel; Shluzas, Lauren Aquino; Pickham, David; Eris, Ozgur; Sadler, Joel; Joshi, Shantanu; Leifer, Larry

2015-01-01

Chronic wounds, including pressure ulcers, compromise the health of 6.5 million Americans and pose an annual estimated burden of $25 billion to the U.S. health care system. When treating chronic wounds, clinicians must use meticulous documentation to determine wound severity and to monitor healing progress over time. Yet, current wound documentation practices using digital photography are often cumbersome and labor intensive. The process of transferring photos into Electronic Medical Records (EMRs) requires many steps and can take several days. Newer smartphone and tablet-based solutions, such as Epic Haiku, have reduced EMR upload time. However, issues still exist involving patient positioning, image-capture technique, and patient identification. In this paper, we present the development and assessment of the SnapCap System for chronic wound photography. Through leveraging the sensor capabilities of Google Glass, SnapCap enables hands-free digital image capture, and the tagging and transfer of images to a patient’s EMR. In a pilot study with wound care nurses at Stanford Hospital (n=16), we (i) examined feature preferences for hands-free digital image capture and documentation, and (ii) compared SnapCap to the state of the art in digital wound care photography, the Epic Haiku application. We used the Wilcoxon Signed-ranks test to evaluate differences in mean ranks between preference options. Preferred hands-free navigation features include barcode scanning for patient identification, Z(15) = -3.873, p < 0.001, r = 0.71, and double-blinking to take photographs, Z(13) = -3.606, p < 0.001, r = 0.71. In the comparison between SnapCap and Epic Haiku, the SnapCap System was preferred for sterile image-capture technique, Z(16) = -3.873, p < 0.001, r = 0.68. Responses were divided with respect to image quality and overall ease of use. The study’s results have contributed to the future implementation of new features aimed at enhancing mobile hands-free digital

Imaging and computational considerations for image computed permeability: Operating envelope of Digital Rock Physics

Science.gov (United States)

Saxena, Nishank; Hows, Amie; Hofmann, Ronny; Alpak, Faruk O.; Freeman, Justin; Hunter, Sander; Appel, Matthias

2018-06-01

This study defines the optimal operating envelope of the Digital Rock technology from the perspective of imaging and numerical simulations of transport properties. Imaging larger volumes of rocks for Digital Rock Physics (DRP) analysis improves the chances of achieving a Representative Elementary Volume (REV) at which flow-based simulations (1) do not vary with change in rock volume, and (2) is insensitive to the choice of boundary conditions. However, this often comes at the expense of image resolution. This trade-off exists due to the finiteness of current state-of-the-art imaging detectors. Imaging and analyzing digital rocks that sample the REV and still sufficiently resolve pore throats is critical to ensure simulation quality and robustness of rock property trends for further analysis. We find that at least 10 voxels are needed to sufficiently resolve pore throats for single phase fluid flow simulations. If this condition is not met, additional analyses and corrections may allow for meaningful comparisons between simulation results and laboratory measurements of permeability, but some cases may fall outside the current technical feasibility of DRP. On the other hand, we find that the ratio of field of view and effective grain size provides a reliable measure of the REV for siliciclastic rocks. If this ratio is greater than 5, the coefficient of variation for single-phase permeability simulations drops below 15%. These imaging considerations are crucial when comparing digitally computed rock flow properties with those measured in the laboratory. We find that the current imaging methods are sufficient to achieve both REV (with respect to numerical boundary conditions) and required image resolution to perform digital core analysis for coarse to fine-grained sandstones.

Epistemic Function and Ontology of Analog and Digital Images

Directory of Open Access Journals (Sweden)

Aleksandra Łukaszewicz Alcaraz

2016-01-01

Full Text Available The important epistemic function of photographic images is their active role in construction and reconstruction of our beliefs concerning the world and human identity, since we often consider photographs as presenting reality or even the Real itself. Because photography can convince people of how different social and ethnic groups and even they themselves look, documentary projects and the dissemination of photographic practices supported the transition from disciplinary society to the present-day society of control. While both analog and digital images are formed from the same basic materia, the ways in which this matter appears are distinctive. In the case of analog photography, we deal with physical and chemical matter, whereas with digital images we face electronic matter. Because digital photography allows endless modification of the image, we can no longer believe in the truthfulness of digital images.

Digital imaging in health care

International Nuclear Information System (INIS)

1987-01-01

This volume describes equipment for the generation and processing of digital images in medicine. Separate chapters deal with international trade i this equipment, with economic and social considerations of digital imaging, with experiences in the use and production of digital imaging equipment and with the current status and likely trends in applications of digital imaging. 84 refs, figs and tabs

The Digital Image Processing And Quantitative Analysis In Microscopic Image Characterization

International Nuclear Information System (INIS)

Ardisasmita, M. Syamsa

2000-01-01

Many electron microscopes although have produced digital images, but not all of them are equipped with a supporting unit to process and analyse image data quantitatively. Generally the analysis of image has to be made visually and the measurement is realized manually. The development of mathematical method for geometric analysis and pattern recognition, allows automatic microscopic image analysis with computer. Image processing program can be used for image texture and structure periodic analysis by the application of Fourier transform. Because the development of composite materials. Fourier analysis in frequency domain become important for measure the crystallography orientation. The periodic structure analysis and crystal orientation are the key to understand many material properties like mechanical strength. stress, heat conductivity, resistance, capacitance and other material electric and magnetic properties. In this paper will be shown the application of digital image processing in microscopic image characterization and analysis in microscopic image

Classifying Physical Morphology of Cocoa Beans Digital Images using Multiclass Ensemble Least-Squares Support Vector Machine

Science.gov (United States)

Lawi, Armin; Adhitya, Yudhi

2018-03-01

The objective of this research is to determine the quality of cocoa beans through morphology of their digital images. Samples of cocoa beans were scattered on a bright white paper under a controlled lighting condition. A compact digital camera was used to capture the images. The images were then processed to extract their morphological parameters. Classification process begins with an analysis of cocoa beans image based on morphological feature extraction. Parameters for extraction of morphological or physical feature parameters, i.e., Area, Perimeter, Major Axis Length, Minor Axis Length, Aspect Ratio, Circularity, Roundness, Ferret Diameter. The cocoa beans are classified into 4 groups, i.e.: Normal Beans, Broken Beans, Fractured Beans, and Skin Damaged Beans. The model of classification used in this paper is the Multiclass Ensemble Least-Squares Support Vector Machine (MELS-SVM), a proposed improvement model of SVM using ensemble method in which the separate hyperplanes are obtained by least square approach and the multiclass procedure uses One-Against- All method. The result of our proposed model showed that the classification with morphological feature input parameters were accurately as 99.705% for the four classes, respectively.

Force-independent distribution of correlated neural inputs to hand muscles during three-digit grasping.

Science.gov (United States)

Poston, Brach; Danna-Dos Santos, Alessander; Jesunathadas, Mark; Hamm, Thomas M; Santello, Marco

2010-08-01

The ability to modulate digit forces during grasping relies on the coordination of multiple hand muscles. Because many muscles innervate each digit, the CNS can potentially choose from a large number of muscle coordination patterns to generate a given digit force. Studies of single-digit force production tasks have revealed that the electromyographic (EMG) activity scales uniformly across all muscles as a function of digit force. However, the extent to which this finding applies to the coordination of forces across multiple digits is unknown. We addressed this question by asking subjects (n = 8) to exert isometric forces using a three-digit grip (thumb, index, and middle fingers) that allowed for the quantification of hand muscle coordination within and across digits as a function of grasp force (5, 20, 40, 60, and 80% maximal voluntary force). We recorded EMG from 12 muscles (6 extrinsic and 6 intrinsic) of the three digits. Hand muscle coordination patterns were quantified in the amplitude and frequency domains (EMG-EMG coherence). EMG amplitude scaled uniformly across all hand muscles as a function of grasp force (muscle x force interaction: P = 0.997; cosines of angle between muscle activation pattern vector pairs: 0.897-0.997). Similarly, EMG-EMG coherence was not significantly affected by force (P = 0.324). However, coherence was stronger across extrinsic than that across intrinsic muscle pairs (P = 0.0039). These findings indicate that the distribution of neural drive to multiple hand muscles is force independent and may reflect the anatomical properties or functional roles of hand muscle groups.

Dupuytren’s disease digital radius IV right hand and carpal tunnel syndrome on ipsilateral hand

Directory of Open Access Journals (Sweden)

Teona Sebe Ioana

2015-11-01

Full Text Available Dupuytren’s contracture is a fibroproliferative disease whose etiology and pathophysiology are unclear and controversial. It is a connective tissue disorder, which takes part in the palmar’s fibromatosis category and has common characteristics with the healing process. Dupuytren’s disease is characterized by the flexion contracture of the hand due to palmar and digital aponevrosis. It generally affects the 4th digital radius, followed by the 5th one. Without surgery, it leads to functional impotence of those digital rays and/or hand. It is associated with other diseases and situational conditions like Peyronie’s disease, the Lederhose disease (plantar fibromatosis, Garrod’s digital knuckle-pads, diabetes, epilepsy, alcoholism, micro traumatisms, stenosing tenosynovitis and not the least with carpal tunnel syndrome. The carpal tunnel syndrome is a peripheral neuropathy with the incarceration of the median nerve at the ARC level, expressed clinically by sensory and motor disturbances in the distribution territory of the median nerve, which cause functional limitations of daily activities of the patient. After the failure of the nonsurgical treatment or the appearance of the motor deficit, is established the open or endoscopic surgical treatment with the release of the median nerve. Postoperative recovery in both diseases is crucial to the functionality of the affected upper limb and to the quality of the patient’s life. The patient, a 61 years old man, admitted to the clinic for the functional impotence of the right hand, for the permanent flexion contracture of the metacarpophalangeal joint (MCP and proximal interphalangeal joint (PIP of the 4th finger with extension deficit, for the damage of the thumb pulp clamp of the 4th finger, for nocturnal paresthesia of fingers I-III and pain that radiates into the fingertips. After clinical, paraclinical, imagistic and electrical investigations, surgery is practiced partial aponevrectomy

Digital imaging in dentistry.

Science.gov (United States)

Essen, S Donovan

2011-01-01

Information technology is vital to operations, marketing, accounting, finance and administration. One of the most exciting and quickly evolving technologies in the modern dental office is digital applications. The dentist is often the business manager, information technology officer and strategic planning chief for his small business. The information systems triangle applies directly to this critical manager supported by properly trained ancillary staff and good equipment. With emerging technology driving all medical disciplines and the rapid pace at which it emerges, it is vital for the contemporary practitioner to keep abreast of the newest information technology developments. This article compares the strategic and operational advantages of digital applications, specifically imaging. The focus of this paper will be on digital radiography (DR), 3D computerized tomography, digital photography and digitally-driven CAD/CAM to what are now considered obsolescing modalities and contemplates what may arrive in the future. It is the purpose of this essay to succinctly evaluate the decisions involved in the role, application and implications of employing this tool in the dental environment

Control Design and Digital Implementation of a Fast 2-Degree-of-Freedom Translational Optical Image Stabilizer for Image Sensors in Mobile Camera Phones.

Science.gov (United States)

Wang, Jeremy H-S; Qiu, Kang-Fu; Chao, Paul C-P

2017-10-13

This study presents design, digital implementation and performance validation of a lead-lag controller for a 2-degree-of-freedom (DOF) translational optical image stabilizer (OIS) installed with a digital image sensor in mobile camera phones. Nowadays, OIS is an important feature of modern commercial mobile camera phones, which aims to mechanically reduce the image blur caused by hand shaking while shooting photos. The OIS developed in this study is able to move the imaging lens by actuating its voice coil motors (VCMs) at the required speed to the position that significantly compensates for imaging blurs by hand shaking. The compensation proposed is made possible by first establishing the exact, nonlinear equations of motion (EOMs) for the OIS, which is followed by designing a simple lead-lag controller based on established nonlinear EOMs for simple digital computation via a field-programmable gate array (FPGA) board in order to achieve fast response. Finally, experimental validation is conducted to show the favorable performance of the designed OIS; i.e., it is able to stabilize the lens holder to the desired position within 0.02 s, which is much less than previously reported times of around 0.1 s. Also, the resulting residual vibration is less than 2.2-2.5 μm, which is commensurate to the very small pixel size found in most of commercial image sensors; thus, significantly minimizing image blur caused by hand shaking.

Applying and extending ISO/TC42 digital camera resolution standards to mobile imaging products

Science.gov (United States)

Williams, Don; Burns, Peter D.

2007-01-01

There are no fundamental differences between today's mobile telephone cameras and consumer digital still cameras that suggest many existing ISO imaging performance standards do not apply. To the extent that they have lenses, color filter arrays, detectors, apertures, image processing, and are hand held, there really are no operational or architectural differences. Despite this, there are currently differences in the levels of imaging performance. These are driven by physical and economic constraints, and image-capture conditions. Several ISO standards for resolution, well established for digital consumer digital cameras, require care when applied to the current generation of cell phone cameras. In particular, accommodation of optical flare, shading non-uniformity and distortion are recommended. We offer proposals for the application of existing ISO imaging resolution performance standards to mobile imaging products, and suggestions for extending performance standards to the characteristic behavior of camera phones.

A CAD system and quality assurance protocol for bone age assessment utilizing digital hand atlas

Science.gov (United States)

Gertych, Arakadiusz; Zhang, Aifeng; Ferrara, Benjamin; Liu, Brent J.

2007-03-01

Determination of bone age assessment (BAA) in pediatric radiology is a task based on detailed analysis of patient's left hand X-ray. The current standard utilized in clinical practice relies on a subjective comparison of the hand with patterns in the book atlas. The computerized approach to BAA (CBAA) utilizes automatic analysis of the regions of interest in the hand image. This procedure is followed by extraction of quantitative features sensitive to skeletal development that are further converted to a bone age value utilizing knowledge from the digital hand atlas (DHA). This also allows providing BAA results resembling current clinical approach. All developed methodologies have been combined into one CAD module with a graphical user interface (GUI). CBAA can also improve the statistical and analytical accuracy based on a clinical work-flow analysis. For this purpose a quality assurance protocol (QAP) has been developed. Implementation of the QAP helped to make the CAD more robust and find images that cannot meet conditions required by DHA standards. Moreover, the entire CAD-DHA system may gain further benefits if clinical acquisition protocol is modified. The goal of this study is to present the performance improvement of the overall CAD-DHA system with QAP and the comparison of the CAD results with chronological age of 1390 normal subjects from the DHA. The CAD workstation can process images from local image database or from a PACS server.

Digital imaging primer

CERN Document Server

Parkin, Alan

2016-01-01

Digital Imaging targets everyyone with an interest in digital imaging, be they professional or private, who uses even quite modest equipment such as a PC, digital camera and scanner, a graphics editor such as Paint, and an inkjet printer. Uniquely, it is intended to fill the gap between highly technical texts for academics (with access to expensive equipment) and superficial introductions for amateurs. The four-part treatment spans theory, technology, programs and practice. Theory covers integer arithmetic, additive and subtractive color, greyscales, computational geometry, and a new presentation of discrete Fourier analysis; Technology considers bitmap file structures, scanners, digital cameras, graphic editors, and inkjet printers; Programs develops several processing tools for use in conjunction with a standard Paint graphics editor and supplementary processing tools; Practice discusses 1-bit, greyscale, 4-bit, 8-bit, and 24-bit images for the practice section. Relevant QBASIC code is supplied an accompa...

Imaging sunlight using a digital spectroheliograph

CERN Document Server

Harrison, Ken M

2016-01-01

Ken M. Harrison's latest book is a complete guide for amateur astronomers who want to obtain detailed narrowband images of the Sun using a digital spectroheliograph (SHG). The SHG allows the safe imaging of the Sun without the expense of commercial ‘etalon’ solar filters. As the supporting software continues to be refined, the use of the digital spectroheliograph will become more and more mainstream and has the potential to replace the expensive solar filters currently in use. The early chapters briefly explain the concept of the SHG and how it can produce an image from the solar spectrum. A comparison of the currently available narrow band solar filters is followed by a detailed analysis of the critical design, construction and assembly features of the SHG. The design and optimum layout of the instrument is discussed to allow evaluation of performance. This information explains how to assemble a fully functional SHG using readily available components. The software required to process the images is exp...

Digital image transformation and rectification of spacecraft and radar images

Science.gov (United States)

Wu, S. S. C.

1985-01-01

The application of digital processing techniques to spacecraft television pictures and radar images is discussed. The use of digital rectification to produce contour maps from spacecraft pictures is described; images with azimuth and elevation angles are converted into point-perspective frame pictures. The digital correction of the slant angle of radar images to ground scale is examined. The development of orthophoto and stereoscopic shaded relief maps from digital terrain and digital image data is analyzed. Digital image transformations and rectifications are utilized on Viking Orbiter and Lander pictures of Mars.

Methods of digital image processing

International Nuclear Information System (INIS)

Doeler, W.

1985-01-01

Increasing use of computerized methods for diagnostical imaging of radiological problems will open up a wide field of applications for digital image processing. The requirements set by routine diagnostics in medical radiology point to picture data storage and documentation and communication as the main points of interest for application of digital image processing. As to the purely radiological problems, the value of digital image processing is to be sought in the improved interpretability of the image information in those cases where the expert's experience and image interpretation by human visual capacities do not suffice. There are many other domains of imaging in medical physics where digital image processing and evaluation is very useful. The paper reviews the various methods available for a variety of problem solutions, and explains the hardware available for the tasks discussed. (orig.) [de

Analog and digital image quality:

OpenAIRE

Sardo, Alberto

2004-01-01

Background. Lastly the X ray facilities are moving to a slow, but continuous process of digitalization. The dry laser printers allow hardcopy images with optimum resolution and contrast for all the modalities. In breast imaging, thedelay of digitalization depends to the high cost of digital systems and, attimes, to the doubts of the diagnostic accuracy of reading the breast digital images. Conclusions. The Screen film mammography (SFM) is the most efficient diagnostic modality to detect the b...

The Image Quality Translator – A Way to Support Specification of Imaging Requirements

DEFF Research Database (Denmark)

Kejser, Ulla Bøgvad; Bech, Mogens

2015-01-01

Archives, libraries, and museums run numerous imaging projects to digitize physical works and collections of cultural heritage. This study presents a tool called the 'Image Quality Translator' that is being designed at the Royal Library to support the planning of digitization projects and to make...... the process of specifying and controlling imaging requirements more efficient. The tool seeks to translate between the language used by collection managers and curators to express needs for image quality, and the more technical terms and metrics used by imaging experts and photographers to express...

Your fate is in your hands? Handedness, digit ratio (2D:4D), and selection to a national talent development system.

Science.gov (United States)

Baker, Joseph; Kungl, Ann-Marie; Pabst, Jan; Strauß, Bernd; Büsch, Dirk; Schorer, Jörg

2013-01-01

Over the past decade a small evidence base has highlighted the potential importance of seemingly innocuous variables related to one's hands, such as hand dominance and the relative length of the second and fourth digits (2D:4D ratio), to success in sport. This study compared 2D:4D digit ratio and handedness among handball players selected to advance in a national talent development system with those not selected. Participants included 480 youth handball players (240 females and 240 males) being considered as part of the talent selection programme for the German Youth National team. Hand dominance and digit ratio were compared to age-matched control data using standard t-tests. There was a greater proportion of left-handers compared to the normal population in males but not in females. There was also a lower digit ratio in both females and males. However, there were no differences between those selected for the next stage of talent development and those not selected on either handedness or digit ratio. These results add support for general effects for both digit ratio and handedness in elite handball; however, these factors seem inadequate to explain talent selection decisions at this level.

Digital stereoscopic imaging

Science.gov (United States)

Rao, A. Ravishankar; Jaimes, Alejandro

1999-05-01

The convergence of inexpensive digital cameras and cheap hardware for displaying stereoscopic images has created the right conditions for the proliferation of stereoscopic imagin applications. One application, which is of growing importance to museums and cultural institutions, consists of capturing and displaying 3D images of objects at multiple orientations. In this paper, we present our stereoscopic imaging system and methodology for semi-automatically capturing multiple orientation stereo views of objects in a studio setting, and demonstrate the superiority of using a high resolution, high fidelity digital color camera for stereoscopic object photography. We show the superior performance achieved with the IBM TDI-Pro 3000 digital camera developed at IBM Research. We examine various choices related to the camera parameters, image capture geometry, and suggest a range of optimum values that work well in practice. We also examine the effect of scene composition and background selection on the quality of the stereoscopic image display. We will demonstrate our technique with turntable views of objects from the IBM Corporate Archive.

Validation of hand and foot anatomical feature measurements from smartphone images

Science.gov (United States)

Amini, Mohammad; Vasefi, Fartash; MacKinnon, Nicholas

2018-02-01

A smartphone mobile medical application, previously presented as a tool for individuals with hand arthritis to assess and monitor the progress of their disease, has been modified and expanded to include extraction of anatomical features from the hand (joint/finger width, and angulation) and foot (length, width, big toe angle, and arch height index) from smartphone camera images. Image processing algorithms and automated measurements were validated by performing tests on digital hand models, rigid plastic hand models, and real human hands and feet to determine accuracy and reproducibility compared to conventional measurement tools such as calipers, rulers, and goniometers. The mobile application was able to provide finger joint width measurements with accuracy better than 0.34 (+/-0.25) millimeters. Joint angulation measurement accuracy was better than 0.50 (+/-0.45) degrees. The automatically calculated foot length accuracy was 1.20 (+/-1.27) millimeters and the foot width accuracy was 1.93 (+/-1.92) millimeters. Hallux valgus angle (used in assessing bunions) accuracy was 1.30 (+/-1.29) degrees. Arch height index (AHI) measurements had an accuracy of 0.02 (+/-0.01). Combined with in-app documentation of symptoms, treatment, and lifestyle factors, the anatomical feature measurements can be used by both healthcare professionals and manufacturers. Applications include: diagnosing hand osteoarthritis; providing custom finger splint measurements; providing compression glove measurements for burn and lymphedema patients; determining foot dimensions for custom shoe sizing, insoles, orthotics, or foot splints; and assessing arch height index and bunion treatment effectiveness.

Diagnostic imaging of the hand

Energy Technology Data Exchange (ETDEWEB)

Schmitt, Rainer [Hospital for Cardiovascular Diseases, Bad Neustadt an der Saale (Germany). Dept. of Radiology; Lanz, Ulrich [Perlach Hospital, Munich (Germany). Dept. of Hand Surgery

2008-07-01

With its complex anatomy and specialized biomechanics, the human hand has always presented physicians with a unique challenge when it comes to diagnosing and treating the diseases that afflict it. And while recent decades have seen a rapid increase in the number of therapeutic options, many diseases and injuries of the hand are still commonly misinterpreted. In diagnostic imaging of the hand, an interdisciplinary team, comprisingspecialists in radiology, surgery, and rheumatology, presents a comprehensive,reliable guide to this topographically intricate area. Highlights include: - More than 1000 high-quality illustrations - All state-of-the-art imaging modalities-including multidetector CT, with 2D displays and 3D reconstructions, and contrast-enhanced MRI with multi-channel, phased-array coils - An overview of all currently used methods of examination - A detailed presentation of the anatomic and functional foundations necessary for diagnosis - Full coverage of all disorders of the hand - Systematic treatment of each disease's definition, pathogenesis, and clinical symptoms, according to a graduated diagnostic plan - Easy-to-use format, featuring crisp images and line drawings seamlessly integrated with concise text, summary tables, and handy checklists - A heavily cross-referenced appendix of differential diagnosis tables - Emphasis on interdisciplinary consultation throughout designed to help both radiologists and clinicians develop the most efficient and effective strategies for evaluating and treating patients, Diagnostic imaging of the hand will leave specialists of all levels with a fresh appreciation for - and a richer understanding of - the expanding array of cutting-edge alternatives for diagnosing and treating disorders of the hand. (orig.)

Diagnostic imaging of the hand

International Nuclear Information System (INIS)

Schmitt, Rainer; Lanz, Ulrich

2008-01-01

With its complex anatomy and specialized biomechanics, the human hand has always presented physicians with a unique challenge when it comes to diagnosing and treating the diseases that afflict it. And while recent decades have seen a rapid increase in the number of therapeutic options, many diseases and injuries of the hand are still commonly misinterpreted. In diagnostic imaging of the hand, an interdisciplinary team, comprisingspecialists in radiology, surgery, and rheumatology, presents a comprehensive,reliable guide to this topographically intricate area. Highlights include: - More than 1000 high-quality illustrations - All state-of-the-art imaging modalities-including multidetector CT, with 2D displays and 3D reconstructions, and contrast-enhanced MRI with multi-channel, phased-array coils - An overview of all currently used methods of examination - A detailed presentation of the anatomic and functional foundations necessary for diagnosis - Full coverage of all disorders of the hand - Systematic treatment of each disease's definition, pathogenesis, and clinical symptoms, according to a graduated diagnostic plan - Easy-to-use format, featuring crisp images and line drawings seamlessly integrated with concise text, summary tables, and handy checklists - A heavily cross-referenced appendix of differential diagnosis tables - Emphasis on interdisciplinary consultation throughout designed to help both radiologists and clinicians develop the most efficient and effective strategies for evaluating and treating patients, Diagnostic imaging of the hand will leave specialists of all levels with a fresh appreciation for - and a richer understanding of - the expanding array of cutting-edge alternatives for diagnosing and treating disorders of the hand. (orig.)

Osteoporosis: a new approach of digital processing of radiological images

International Nuclear Information System (INIS)

Salles, Adilson Dias; Braz, Valeria Silva

1998-01-01

The authors applied a method based on digital processing of radiological images (fast Fourier transform) to analyze the radius distal epiphysis and calcaneus spongy bone architecture. The study revealed distinct patterns of trabecular distribution. Prior studies about osteoporosis have focused on bone density quantification and its role on fracture prediction. However, resistance to fractures (mechanical strength) is also determined by structural arrangement of bone. THe digital processing (spectral analysis) was applied to radiological images of the radius and calcaneus from 15 normal and osteopenic individuals. Normal bone trabeculae showed an individualized behavior (stress lines). On the other hand, porotic bone trabeculae revealed a diffuse pattern (honey comb). The scattered frequency components showed that the porotic bone trabeculae were remodeled. This process would be responsible for the maintenance of its physical properties. (author)

Digital vascular imaging

International Nuclear Information System (INIS)

Ludwig, J.W.; Engels, B.C.H.

1981-01-01

Digitalizing videosignals from an image intensifying TV-chain, followed by subtraction, contrast intensifying, and reformation to analogous signal deliver angiography pictures of high quality after intravenous injection of the contrast medium. As the examination is only little invasive it can be carried out on outdoor patients or in the polyclinics. The possibilities of the digital vessel imagination (DVI) are shown at vessel images of different parts of the body; a 36 cm image intensifyer which can be switched to 3 different sorts of operation and has a plumbicon-TV recording tube is used as receiver. (orig.) [de

Digital X-ray Imaging in Dentistry

International Nuclear Information System (INIS)

Kim, Eun Kyung

1999-01-01

In dentistry, Radio Visio Graphy was introduced as a first electronic dental x-ray imaging modality in 1989. Thereafter, many types of direct digital radiographic systems have been produced in the last decade. They are based either on charge-coupled device (CCD) or on storage phosphor technology. In addition, new types of digital radiographic system using amorphous selenium, image intensifier etc. are under development. Advantages of digital radiographic system are elimination of chemical processing, reduction in radiation dose, image processing, computer storage, electronic transfer of images and so on. Image processing includes image enhancement, image reconstruction, digital subtraction, etc. Especially digital subtraction and reconstruction can be applied in many aspects of clinical practice and research. Electronic transfer of images enables filmless dental hospital and teleradiology/teledentistry system. Since the first image management and communications system (IMACS) for dentomaxillofacial radiology was reported in 1992, IMACS in dental hospital has been increasing. Meanwhile, researches about computer-assisted diagnosis, such as structural analysis of bone trabecular patterns of mandible, feature extraction, automated identification of normal landmarks on cephalometric radiograph and automated image analysis for caries or periodontitis, have been performed actively in the last decade. Further developments in digital radiographic imaging modalities, image transmission system, imaging processing and automated analysis software will change the traditional clinical dental practice in the 21st century.

Digital X-ray Imaging in Dentistry

Energy Technology Data Exchange (ETDEWEB)

Kim, Eun Kyung [Dept. of Oral and Maxillofacial Radiology, College of Dentistry, Dankook University, Yongin (Korea, Republic of)

1999-08-15

In dentistry, Radio Visio Graphy was introduced as a first electronic dental x-ray imaging modality in 1989. Thereafter, many types of direct digital radiographic systems have been produced in the last decade. They are based either on charge-coupled device (CCD) or on storage phosphor technology. In addition, new types of digital radiographic system using amorphous selenium, image intensifier etc. are under development. Advantages of digital radiographic system are elimination of chemical processing, reduction in radiation dose, image processing, computer storage, electronic transfer of images and so on. Image processing includes image enhancement, image reconstruction, digital subtraction, etc. Especially digital subtraction and reconstruction can be applied in many aspects of clinical practice and research. Electronic transfer of images enables filmless dental hospital and teleradiology/teledentistry system. Since the first image management and communications system (IMACS) for dentomaxillofacial radiology was reported in 1992, IMACS in dental hospital has been increasing. Meanwhile, researches about computer-assisted diagnosis, such as structural analysis of bone trabecular patterns of mandible, feature extraction, automated identification of normal landmarks on cephalometric radiograph and automated image analysis for caries or periodontitis, have been performed actively in the last decade. Further developments in digital radiographic imaging modalities, image transmission system, imaging processing and automated analysis software will change the traditional clinical dental practice in the 21st century.

Digital imaging in cardiovascular radiology

International Nuclear Information System (INIS)

Heintzen, P.H.; Brennecke, R.

1983-01-01

The present book contains 27 papers presented at an international symposium on digital imaging in cardiovascular radiology held in Kiel in 1982. The main themes were as follows. Introductory reviews, digital systems for X-ray video imaging, quantitative X-ray image analysis, and clinical applications. (MG)

Managing digitally formatted diagnostic image data

International Nuclear Information System (INIS)

Templeton, A.W.; Dwyer, S.J.

1985-01-01

Diagnostic radiologists are very comfortable using analog radiographic film and interpreting its recorded images. To improve patient care, the radiologist has sought the finest quality radiographic film for use with the best radiographic imaging systems. The proper choice and use of x-ray tubes, generators, film-screen combinations, and contrast media has occupied the professional attention of the radiologist since the inception of radiology. Image quality can be significantly improved with digitally formatted diagnostic imaging systems by providing dynamic ranges in excess of those possible with analog x-ray films. In a CT scanner, the digital acquisition and reconstruction system can obtain a dynamic range (contrast resolution) of 10,000 to 1. Digital subtraction angiography systems achieve 10-bit dynamic ranges for each of the acquired television frames. Increases in the dynamic ranges of the various imaging modalities have been coupled with improved spatial resolution. A digitally formatted image is a two-dimensional, numerical array of discrete image elements. Each picture element is called a pixel. Each pixel has a discrete size. Figure 15.1 illustrates a digitally formatted image depicting the spatial resolution, array size, and quantization or numerical range of the pixel values. Currently, 512 x 512 image arrays are standard. Development of 1024 x 1024 digital arrays are underway. Significant improvements have also been achieved in the rates at which digital diagnostic imaging data can be acquired, manipulated, and archived

Could digital imaging be an alternative for digital colorimeters?

Science.gov (United States)

Caglar, Alper; Yamanel, Kivanc; Gulsahi, Kamran; Bagis, Bora; Ozcan, Mutlu

2010-12-01

This study evaluated the colour parameters of composite and ceramic shade guides determined using a colorimeter and digital imaging method with illuminants at different colour temperatures. Two different resin composite shade guides, namely Charisma (Heraeus Kulzer) and Premise (Kerr Corporation), and two different ceramic shade guides, Vita Lumin Vacuum (VITA Zahnfabrik) and Noritake (Noritake Co.), were evaluated at three different colour temperatures (2,700 K, 2,700-6,500 K, and 6500 K) of illuminants. Ten shade tabs were selected (A1, A2, A3, A3,5, A4, B1, B2, B3, C2 and C3) from each shade guide. CIE Lab values were obtained using digital imaging and a colorimeter (ShadeEye NCC Dental Chroma Meter, Shofu Inc.). The data were analysed using two-way ANOVA, and Pearson's correlation. While mean L* values of both composite and ceramic shade guides were not affected from the colour temperature, L* values obtained with the colorimeter showed significantly lower values than those of the digital imaging (p colorimeter and digital imaging did not show significant differences (p > 0.05). For both composite and ceramic shade guides, L* and b* values obtained from colorimeter and digital imaging method presented a high level of correlation. High-level correlations were also acquired for a* values in all shade guides except for the Charisma composite shade guide. Digital imaging method could be an alternative for the colorimeters unless the proper object-camera distance, digital camera settings and suitable illumination conditions could be supplied. However, variations in shade guides, especially for composites, may affect the correlation.

Digital imaging in diagnostic radiology

International Nuclear Information System (INIS)

Newell, J.D. Jr.; Kelsey, C.A.

1990-01-01

This monograph on digital imaging provides a basic overview of this field at the present time. This paper covers clinical application, including subtraction angiography; chest radiology; genitourinary, gastrointestinal, and breast radiology; and teleradiology. The chest section also includes an explanation of multiple beam equalization radiography. The remaining chapters discuss some of the technical aspects of digital radiology. It includes the basic technology of digital radiography, image compression, and reconstruction information on the economics of digital radiography

Digital image monitoring to optimise safe port operation

CSIR Research Space (South Africa)

Phelp, D

2008-11-01

Full Text Available This paper describes a low cost video system ‘Harbour Watch’, which can be used to support safe port operations, especially in developing countries. Preset digital images are geo-referenced and then archived for later analysis to improve...

Digital image intensifier radiography: first experiences with the DSI (Digital Spot Imaging)

International Nuclear Information System (INIS)

Rueckforth, J.; Wein, B.; Stargardt, A.; Guenther, R.W.

1995-01-01

We performed a comparative study of digitally and conventionally acquired images in gastrointestinal examinations. Radiation dose and spatial resolution were determined in a water phantom. In 676 examinations with either conventional or digital imaging (system: Diagnost 76, DSI) the number of images and the duration of the fluoroscopy time were compared. 101 examinations with digital as well as conventional documentation were evaluated by using 5 criteria describing the diagnostic performance. The entrance dose of the DSI is 12% to 36% of the film/screen system and the spatial resolution of the DSI may be better than that of a film/screen system with a speed of 200. The fluoroscopy time shows no significant difference between DSI and the film/screen technique. In 2 of 4 examination modes significantly more images were produced by the DSI. With exception of the criterion of edge sharpness, DSI yields a significantly inferior assessment compared with the film/screen technique. (orig./MG) [de

Digital image analysis of NDT radiographs

International Nuclear Information System (INIS)

Graeme, W.A. Jr.; Eizember, A.C.; Douglass, J.

1989-01-01

Prior to the introduction of Charge Coupled Device (CCD) detectors the majority of image analysis performed on NDT radiographic images was done visually in the analog domain. While some film digitization was being performed, the process was often unable to capture all the usable information on the radiograph or was too time consuming. CCD technology now provides a method to digitize radiographic film images without losing the useful information captured in the original radiograph in a timely process. Incorporating that technology into a complete digital radiographic workstation allows analog radiographic information to be processed, providing additional information to the radiographer. Once in the digital domain, that data can be stored, and fused with radioscopic and other forms of digital data. The result is more productive analysis and management of radiographic inspection data. The principal function of the NDT Scan IV digital radiography system is the digitization, enhancement and storage of radiographic images

Digital Images and Globalized Conflict

DEFF Research Database (Denmark)

Blaagaard, Bolette; Mortensen, Mette; Neumayer, Christina

2017-01-01

As the number of digital images of globalized conflicts online grow, critical examination of their impact and consequence is timely. This editorial provides an overview of digital images and globalized conflict as a field of study by discussing regimes of visibility and invisibility, proximity...... of conflict-related images raise issues of knowledge production and research....

Optimal image resolution for digital storage of radiotherapy-planning images

International Nuclear Information System (INIS)

Baba, Yuji; Furusawa, Mitsuhiro; Murakami, Ryuji; Baba, Takashi; Yokoyama, Toshimi; Nishimura, Ryuichi; Takahashi, Mutsumasa

1998-01-01

Purpose: To evaluate the quality of digitized radiation-planning images at different resolution and to determine the optimal resolution for digital storage. Methods and Materials: Twenty-five planning films were scanned and digitized using a film scanner at a resolution of 72 dots per inch (dpi) with 8-bit depth. The resolution of scanned images was reduced to 48, 36, 24, and 18 dpi using computer software. Image qualities of these five images (72, 48, 36, 24, and 18 dpi) were evaluated and given scores (4 = excellent; 3 = good; 2 = fair; and 1 = poor) by three radiation oncologists. An image data compression algorithm by the Joint Photographic Experts Group (JPEG) (not reversible and some information will be lost) was also evaluated. Results: The scores of digitized images with 72, 48, 36, 24, and 17 dpi resolution were 3.8 ± 0.3, 3.5 ± 0.3, 3.3 ± 0.5, 2.7 ± 0.5, and 1.6 ± 0.3, respectively. The quality of 36-dpi images were definitely worse compared to 72-dpi images, but were good enough as planning films. Digitized planning images with 72- and 36-dpi resolution requires about 800 and 200 KBytes, respectively. The JPEG compression algorithm produces little degradation in 36-dpi images at compression ratios of 5:1. Conclusion: The quality of digitized images with 36-dpi resolution was good enough as radiation-planning images and required 200 KBytes/image

Diagnostic image quality of video-digitized chest images

International Nuclear Information System (INIS)

Winter, L.H.; Butler, R.B.; Becking, W.B.; Warnars, G.A.O.; Haar Romeny, B. ter; Ottes, F.P.; Valk, J.-P.J. de

1989-01-01

The diagnostic accuracy obtained with the Philips picture archiving and communications subsystem was investigated by means of an observer performance study using receiver operating characteristic (ROC) analysis. The image qualities of conventional films and video digitized images were compared. The scanner had a 1024 x 1024 x 8 bit memory. The digitized images were displayed on a 60 Hz interlaced display monitor 1024 lines. Posteroanterior (AP) roetgenograms of a chest phantom with superimposed simulated interstitial pattern disease (IPD) were produced; there were 28 normal and 40 abnormal films. Normal films were produced by the chest phantom alone. Abnormal films were taken of the chest phantom with varying degrees of superimposed simulated intersitial disease (PND) for an observer performance study, because the results of a simulated interstitial pattern disease study are less likely to be influenced by perceptual capabilities. The conventional films and the video digitized images were viewed by five experienced observers during four separate sessions. Conventional films were presented on a viewing box, the digital images were displayed on the monitor described above. The presence of simulated intersitial disease was indicated on a 5-point ROC certainty scale by each observer. We analyzed the differences between ROC curves derived from correlated data statistically. The mean time required to evaluate 68 digitized images is approximately four times the mean time needed to read the convential films. The diagnostic quality of the video digitized images was significantly lower (at the 5% level) than that of the conventional films (median area under the curve (AUC) of 0.71 and 0.94, respectively). (author). 25 refs.; 2 figs.; 4 tabs

Digital image processing of periapical radiographs with low dose of radiation

International Nuclear Information System (INIS)

Kerbauy, Warley David; Moraes, Luiz Cesar de

1996-01-01

The aim of the study was to evaluate whether digitized images obtained from peri apical radiographs taken with low dose of radiation could be improved with the aid of a computer software (Photo Styler) for digital treatment. Serial and standardized radiographs of molar and pre molar areas were studied. A total of 57 images equivalent to the radiographs taken with reduced exposure time (60 and 80% of the time considered normal), digitized and treated, were submitted to the evaluation of seven examiners which compared them with those images without treatment. It was verified that about 80% of the images equivalent to the radiographs taken with 60% reduction of ordinary exposure time were considered to having quality for supporting diagnosis. As for the images taken with 80% reduction of ordinary exposure time, about 50% of them were considered suitable for the same purpose. (author)

The Neuro-Image: Alain Resnais's Digital Cinema without the Digits

NARCIS (Netherlands)

Pisters, P.

2011-01-01

This paper proposes to read cinema in the digital age as a new type of image, the neuroimage. Going back to Gilles Deleuze's cinema books and it is argued that the neuro-image is based in the future. The cinema of Alain Resnais is analyzed as a neuro-image and digital cinema .

Three-dimensional facial digitization using advanced digital image correlation.

Science.gov (United States)

Nguyen, Hieu; Kieu, Hien; Wang, Zhaoyang; Le, Hanh N D

2018-03-20

Presented in this paper is an effective technique to acquire the three-dimensional (3D) digital images of the human face without the use of active lighting and artificial patterns. The technique is based on binocular stereo imaging and digital image correlation, and it includes two key steps: camera calibration and image matching. The camera calibration involves a pinhole model and a bundle-adjustment approach, and the governing equations of the 3D digitization process are described. For reliable pixel-to-pixel image matching, the skin pores and freckles or lentigines on the human face serve as the required pattern features to facilitate the process. It employs feature-matching-based initial guess, multiple subsets, iterative optimization algorithm, and reliability-guided computation path to achieve fast and accurate image matching. Experiments have been conducted to demonstrate the validity of the proposed technique. The simplicity of the approach and the affordable cost of the implementation show its practicability in scientific and engineering applications.

The hand of birds revealed by early ostrich embryos

Science.gov (United States)

Feduccia, Alan; Nowicki, Julie

2002-08-01

The problem of resolving the homology of the digits of the avian hand has been framed as a conflict between paleontological and embryological evidence, the former thought to support a hand composed of digits I, II, III, because of similarity of the phalangeal formulae of the earliest known bird Archaeopteryx to that of Mesozoic pentadactyl archosaurs, while embryological evidence has traditionally favored a II, III, IV avian hand. We have identified the critical developmental period for the major features of the avian skeleton in a primitive bird, the ostrich. Analysis of digit anlagen in the avian hand has revealed those for digits/metacarpals I and V, thus confirming previous embryological studies that indirectly suggested that the avian hand comprises digits II, III, IV, and was primitively pentadactyl.

Whole slide images and digital media in pathology education, testing, and practice: the Oklahoma experience.

Science.gov (United States)

Fung, Kar-Ming; Hassell, Lewis A; Talbert, Michael L; Wiechmann, Allan F; Chaser, Brad E; Ramey, Joel

2012-01-01

Examination of glass slides is of paramount importance in pathology training. Until the introduction of digitized whole slide images that could be accessed through computer networks, the sharing of pathology slides was a major logistic issue in pathology education and practice. With the help of whole slide images, our department has developed several online pathology education websites. Based on a modular architecture, this program provides online access to whole slide images, still images, case studies, quizzes and didactic text at different levels. Together with traditional lectures and hands-on experiences, it forms the back bone of our histology and pathology education system for residents and medical students. The use of digitized whole slide images has a.lso greatly improved the communication between clinicians and pathologist in our institute.

Digital Image Quantitative Evaluations for Low Cost Film Digitizers Height Determination

International Nuclear Information System (INIS)

Khairul Anuar Mohd Salleh; Arshad Yassin; Ahmad Nasir Yusof; Noorhazleena Azaman

2016-01-01

Non Destructive Testing (NDT) technology contributes significant improvement to the quality of industrial products, and the integrity of equipment and plants. Introduction of powerful computers and reliable imaging technology has had significant impact on the traditional nuclear based NDT technology. Demand for faster, reliable, low cost, and flexible technology is rapidly increased. With the growing demand for more efficient digital archiving, digital image analysis, and reporting results with a low cost technology, one cannot deny the importance of having another cheaper solution. This project will apply fundamental principle of image digitization to be used in building up a low cost film digitization solution. The height of the film digitization was carefully determined by examining each digital images produced. Three (3) repetitive quantitative evaluations (Modulation Transfer Function [MTF], Characteristic Transfer Curve [CTC], and Contrast to Noise Ratio [CNR]) were performed at different condition to assist with the determination of the low cost film digitizers height. All 3 evaluations were successfully applied and the most appropriate height was successfully determined. (author)

Temporary Nerve Block at Selected Digits Revealed Hand Motor Deficits in Grasping Tasks

Directory of Open Access Journals (Sweden)

Aude Carteron

2016-11-01

Full Text Available Peripheral sensory feedback plays a crucial role in ensuring correct motor execution throughout hand grasp control. Previous studies utilized local anesthesia to deprive somatosensory feedback in the digits or hand, observations included sensorimotor deficits at both corticospinal and peripheral levels. However, the questions of how the disturbed and intact sensory input integrate and interact with each other to assist the motor program execution, and whether the motor coordination based on motor output variability between affected and non-affected elements (e.g., digits becomes interfered by the local sensory deficiency, have not been answered. The current study aims to investigate the effect of peripheral deafferentation through digital nerve blocks at selective digits on motor performance and motor coordination in grasp control. Our results suggested that the absence of somatosensory information induced motor deficits in hand grasp control, as evidenced by reduced maximal force production ability in both local and non-local digits, impairment of force and moment control during object lift and hold, and attenuated motor synergies in stabilizing task performance variables, namely the tangential force and moment of force. These findings implied that individual sensory input is shared across all the digits and the disturbed signal from local sensory channel(s has a more comprehensive impact on the process of the motor output execution in the sensorimotor integration process. Additionally, a feedback control mechanism with a sensation-based component resides in the formation process for the motor covariation structure.

Digital fluoroscopy: a new development in medical imaging

International Nuclear Information System (INIS)

Maher, K.P.; Malone, J.F.; Dublin Inst. of Technology

1986-01-01

Medical fluoroscopy is briefly reviewed and video-image digitization is described. Image processing requirements and image processors available for digital fluoroscopy are discussed in detail. Specific reference is made to an application of digital fluoroscopy in the imaging of blood-vessels. This application involves an image substraction technique which is referred to as digital subtraction angiography (DSA). A number of DSA images of relevance to the discussion are included. (author)

Specters in the Archive: Faculty Digital Image Collections and the Problems of Invisibility

Science.gov (United States)

Beaudoin, Joan E.

2011-01-01

This paper presents the findings of a research study which investigated the digital preservation practices among two faculty user groups, archeologists and art historians. This faculty's knowledge of digital preservation practices and their perceptions and emotions concerning the digital images they had created and, or collected to support their…

X-ray images in the digital mode

International Nuclear Information System (INIS)

Buchmann, F.; Balter, S.

1981-01-01

In addition to computed tomography which presents actually the most important processing and transfer procedure of digital X-ray images, application of real time addition and substraction of X-ray images in a digital mode has found considerable interest. An estimation of the information contents of both digital and analog images is made in close relation to applications. As example of an image processing system on digital base a recently developed system for intravenous arteriography is described: the Philips-DVI. (orig.) [de

Study on the Image Quality Comparison between in Digital RT and Film RT

International Nuclear Information System (INIS)

Park, Sang Ki; Ahn, Yean Shik; Gil, Doo Song

2011-01-01

Conventional film radiographic test has been generally and widely used in the inspection on the weldment for quality assurance. On the other hand, since the analog RT is well known for typical time and cost consuming method with complex process of inspection, the industry has researched various ways how to improve radiographic test technology. In this study, we verified the fact that digital RT provides a lot more benefit in effectively detecting defects, ever film details, through digital processing of image enhancement, compared to film RT. As a result, we reached conclusion that digital RT is positively able to replace the film RT in industry in part or in whole

Image processing techniques for digital orthophotoquad production

Science.gov (United States)

Hood, Joy J.; Ladner, L. J.; Champion, Richard A.

1989-01-01

Orthophotographs have long been recognized for their value as supplements or alternatives to standard maps. Recent trends towards digital cartography have resulted in efforts by the US Geological Survey to develop a digital orthophotoquad production system. Digital image files were created by scanning color infrared photographs on a microdensitometer. Rectification techniques were applied to remove tile and relief displacement, thereby creating digital orthophotos. Image mosaicking software was then used to join the rectified images, producing digital orthophotos in quadrangle format.

Functional and cosmetic outcome of single-digit ray amputation in hand.

Science.gov (United States)

Bhat, A K; Acharya, A M; Narayanakurup, J K; Kumar, B; Nagpal, P S; Kamath, A

2017-12-01

To assess patient satisfaction, functional and cosmetic outcomes of single-digit ray amputation in hand and identify factors that might affect the outcome. Forty-five patients who underwent ray amputation were evaluated, 37 males and eight females whose mean age was 36.6 years ranging between 15 and 67 years. Twenty-eight patients had dominant hand involvement. Twenty-one patients underwent primary ray amputation, and 24 patients had secondary ray amputation. Eight out of the 23 patients with central digit injuries underwent transposition. Grip strength, pinch strength, tactile sensibility and functional evaluation using Result Assessment Scale (RAS) and DASH score were analysed. Cosmetic assessment was performed using visual analogue scale (VAS) for cosmesis. Median time of assessment after surgery was 20 months. Average loss of grip strength and pinch strength was found to be 43.3 and 33.6%, respectively. Average RAS score was 3.75. Median DASH score was 23.4. Eighty-three percentage of patients had excellent or good cosmesis on the VAS. Transposition causes significant increase in DASH scores for central digit ray amputations but was cosmetically superior. Middle finger ray amputation had the maximum loss of grip strength, and index finger ray amputation had greater loss of pinch strength. Affection of neighbouring digits caused greater grip and pinch loss, and a higher DASH score. Primary ray resection decreased the total disability and eliminated the costs of a second procedure. Following ray amputation, one can predict an approximate 43.3% loss of grip strength and 33.6% loss of pinch strength. The patients can be counselled regarding the expected time off from work, amount of disability and complications after a single-digit ray amputation. Majority of the patients can return to the same occupation after a period of dedicated hand therapy. Therapeutic, Level III.

Surgical amputation of the digit: an investigation into the technical variations among hand surgeons.

Science.gov (United States)

Li, Andrew; Meunier, Matthew; Rennekampff, Hans-Oliver; Tenenhaus, Mayer

2013-01-01

Digital injuries are common and frequently complicate occupational hazards and trauma. The management of these injuries often necessitates digital amputation, and a variety of different amputation techniques are advocated and employed by hand surgeons. In this survey study, we investigate the variation in technical detail among a group of hand surgeons when performing digital amputations, specifically the preferred management of the residual articular cartilage, transected nerves, and phalangeal contouring. We reviewed the literature on techniques in digital amputation and created a 7-question survey that targeted controversial issues within this specific topic. We then sent this survey electronically to the members of the American Society for Surgery of the Hand and reviewed the responses of the respondents (n = 592, 20%). There was a mixed response regarding whether or not to remove the articular cartilage when disarticulating, nearly a 50% split between the respondents. Most would perform a "pull and resect" technique for transected nerves. Phalangeal contouring was generally agreed upon, though the technique in doing so varied from performing condylectomies, to bony contouring only, to some combination of both. We detected a substantial variation in technique among our group of hand surgeons regarding the treatment of articular cartilage and the method of phalangeal contouring. There was more consensus regarding the treatment of transected nerve. It is interesting that to date, the aforementioned issues in digital amputation have not been critically evaluated by definitive and well-controlled studies.

Image processing in digital chest radiography

International Nuclear Information System (INIS)

Manninen, H.; Partanen, K.; Lehtovirta, J.; Matsi, P.; Soimakallio, S.

1992-01-01

The usefulness of digital image processing of chest radiographs was evaluated in a clinical study. In 54 patients, chest radiographs in the posteroanterior projection were obtained by both 14 inch digital image intensifier equipment and the conventional screen-film technique. The digital radiographs (512x512 image format) viewed on a 625 line monitor were processed in 3 different ways: 1.standard display; 2.digital edge enhancement for the standard display; 3.inverse intensity display. The radiographs were interpreted independently by 3 radiologists. Diagnoses were confirmed by CT, follow-up radiographs and clinical records. Chest abnormalities of the films analyzed included 21 primary lung tumors, 44 pulmonary nodules, 16 cases with mediastinal disease, 17 with pneumonia /atelectasis. Interstitial lung disease, pleural plaques, and pulmonary emphysema were found in 30, 18 and 19 cases respectively. Sensitivity of conventional radiography when averaged overall findings was better than that of digital techniques (P<0.001). Differences in diagnostic accuracy measured by sensitivity and specificity between the 3 digital display modes were small. Standard image display showed better sensitivity for pulmonary nodules (0.74 vs 0.66; P<0.05) but poorer specificity for pulmonary emphysema (0.85 vs 0.93; P<0.05) compared with inverse intensity display. It is concluded that when using 512x512 image format, the routine use of digital edge enhancement and tone reversal at digital chest radiographs is not warranted. (author). 12 refs.; 4 figs.; 2 tabs

Compression and archiving of digital images

International Nuclear Information System (INIS)

Huang, H.K.

1988-01-01

This paper describes the application of a full-frame bit-allocation image compression technique to a hierarchical digital image archiving system consisting of magnetic disks, optical disks and an optical disk library. The digital archiving system without the compression has been in clinical operation in the Pediatric Radiology for more than half a year. The database in the system consists of all pediatric inpatients including all images from computed radiography, digitized x-ray films, CT, MR, and US. The rate of image accumulation is approximately 1,900 megabytes per week. The hardware design of the compression module is based on a Motorola 68020 microprocessor, A VME bus, a 16 megabyte image buffer memory board, and three Motorola digital signal processing 56001 chips on a VME board for performing the two-dimensional cosine transform and the quantization. The clinical evaluation of the compression module with the image archiving system is expected to be in February 1988

Advanced digital image archival system using MPEG technologies

Science.gov (United States)

Chang, Wo

2009-08-01

Digital information and records are vital to the human race regardless of the nationalities and eras in which they were produced. Digital image contents are produced at a rapid pace from cultural heritages via digitalization, scientific and experimental data via high speed imaging sensors, national defense satellite images from governments, medical and healthcare imaging records from hospitals, personal collection of photos from digital cameras. With these mass amounts of precious and irreplaceable data and knowledge, what standards technologies can be applied to preserve and yet provide an interoperable framework for accessing the data across varieties of systems and devices? This paper presents an advanced digital image archival system by applying the international standard of MPEG technologies to preserve digital image content.

New directions in pediatric digital imaging

International Nuclear Information System (INIS)

Fletcher, B.D.; Adams, R.B.; Blackham, W.C.

1985-01-01

In this chapter the authors describe several simple experiments performed utilizing digital equipment which apply to clinical situations in pediatrics and which suggest future directions for research in digital imaging. They also discuss experimental systems which they believe will overcome certain limitations of current equipment and might be applicable to pediatric digital imaging in the future

Application of digital-image-correlation techniques in analysing ...

Indian Academy of Sciences (India)

Basis theory of strain analysis using the digital image correlation method .... Type 304N Stainless Steel (Modulus of Elasticity = 193 MPa, Tensile Yield .... also proves the accuracy of the qualitative analyses by using the DIC ... We thank the National Science Council of Taiwan for supporting this research through grant. No.

Hand and foot pressures in the aye-aye (Daubentonia madagascariensis) reveal novel biomechanical trade-offs required for walking on gracile digits.

Science.gov (United States)

Kivell, Tracy L; Schmitt, Daniel; Wunderlich, Roshna E

2010-05-01

Arboreal animals with prehensile hands must balance the complex demands of bone strength, grasping and manipulation. An informative example of this problem is that of the aye-aye (Daubentonia madagascariensis), a rare lemuriform primate that is unusual in having exceptionally long, gracile fingers specialized for foraging. In addition, they are among the largest primates to engage in head-first descent on arboreal supports, a posture that should increase loads on their gracile digits. We test the hypothesis that aye-ayes will reduce pressure on their digits during locomotion by curling their fingers off the substrate. This hypothesis was tested using simultaneous videographic and pressure analysis of the hand, foot and digits for five adult aye-ayes during horizontal locomotion and during ascent and descent on a 30 degrees instrumented runway. Aye-ayes consistently curled their fingers during locomotion on all slopes. When the digits were in contact with the substrate, pressures were negligible and significantly less than those experienced by the palm or pedal digits. In addition, aye-ayes lifted their hands vertically off the substrate instead of 'toeing-off' and descended head-first at significantly slower speeds than on other slopes. Pressure on the hand increased during head-first descent relative to horizontal locomotion but not as much as the pressure increased on the foot during ascent. This distribution of pressure suggests that aye-ayes shift their weight posteriorly during head-first descent to reduce loads on their gracile fingers. This research demonstrates several novel biomechanical trade-offs to deal with complex functional demands on the mammalian skeleton.

Digital image envelope: method and evaluation

Science.gov (United States)

Huang, H. K.; Cao, Fei; Zhou, Michael Z.; Mogel, Greg T.; Liu, Brent J.; Zhou, Xiaoqiang

2003-05-01

Health data security, characterized in terms of data privacy, authenticity, and integrity, is a vital issue when digital images and other patient information are transmitted through public networks in telehealth applications such as teleradiology. Mandates for ensuring health data security have been extensively discussed (for example The Health Insurance Portability and Accountability Act, HIPAA) and health informatics guidelines (such as the DICOM standard) are beginning to focus on issues of data continue to be published by organizing bodies in healthcare; however, there has not been a systematic method developed to ensure data security in medical imaging Because data privacy and authenticity are often managed primarily with firewall and password protection, we have focused our research and development on data integrity. We have developed a systematic method of ensuring medical image data integrity across public networks using the concept of the digital envelope. When a medical image is generated regardless of the modality, three processes are performed: the image signature is obtained, the DICOM image header is encrypted, and a digital envelope is formed by combining the signature and the encrypted header. The envelope is encrypted and embedded in the original image. This assures the security of both the image and the patient ID. The embedded image is encrypted again and transmitted across the network. The reverse process is performed at the receiving site. The result is two digital signatures, one from the original image before transmission, and second from the image after transmission. If the signatures are identical, there has been no alteration of the image. This paper concentrates in the method and evaluation of the digital image envelope.

Image quality in digital radiography

International Nuclear Information System (INIS)

Kuhn, H.

1986-01-01

The contribution deals with the potentials of digital radiography and critically evaluates the advantages of drawbacks of the image intensifier-tv-digital system; digitalisation of the X-ray film and scanning of luminescent storage foils. The evaluation is done in comparison with the image quality of the traditional, large-size X-ray picture. (orig.) [de

Image rejects in general direct digital radiography

International Nuclear Information System (INIS)

Hofmann, Bjørn; Rosanowsky, Tine Blomberg; Jensen, Camilla; Wah, Kenneth Hong Ching

2015-01-01

The number of rejected images is an indicator of image quality and unnecessary imaging at a radiology department. Image reject analysis was frequent in the film era, but comparably few and small studies have been published after converting to digital radiography. One reason may be a belief that rejects have been eliminated with digitalization. To measure the extension of deleted images in direct digital radiography (DR), in order to assess the rates of rejects and unnecessary imaging and to analyze reasons for deletions, in order to improve the radiological services. All exposed images at two direct digital laboratories at a hospital in Norway were reviewed in January 2014. Type of examination, number of exposed images, and number of deleted images were registered. Each deleted image was analyzed separately and the reason for deleting the image was recorded. Out of 5417 exposed images, 596 were deleted, giving a deletion rate of 11%. A total of 51.3% were deleted due to positioning errors and 31.0% due to error in centering. The examinations with the highest percentage of deleted images were the knee, hip, and ankle, 20.6%, 18.5%, and 13.8% respectively. The reject rate is at least as high as the deletion rate and is comparable with previous film-based imaging systems. The reasons for rejection are quite different in digital systems. This falsifies the hypothesis that digitalization would eliminates rejects. A deleted image does not contribute to diagnostics, and therefore is an unnecessary image. Hence, the high rates of deleted images have implications for management, training, education, as well as for quality

Image rejects in general direct digital radiography.

Science.gov (United States)

Hofmann, Bjørn; Rosanowsky, Tine Blomberg; Jensen, Camilla; Wah, Kenneth Hong Ching

2015-10-01

The number of rejected images is an indicator of image quality and unnecessary imaging at a radiology department. Image reject analysis was frequent in the film era, but comparably few and small studies have been published after converting to digital radiography. One reason may be a belief that rejects have been eliminated with digitalization. To measure the extension of deleted images in direct digital radiography (DR), in order to assess the rates of rejects and unnecessary imaging and to analyze reasons for deletions, in order to improve the radiological services. All exposed images at two direct digital laboratories at a hospital in Norway were reviewed in January 2014. Type of examination, number of exposed images, and number of deleted images were registered. Each deleted image was analyzed separately and the reason for deleting the image was recorded. Out of 5417 exposed images, 596 were deleted, giving a deletion rate of 11%. A total of 51.3% were deleted due to positioning errors and 31.0% due to error in centering. The examinations with the highest percentage of deleted images were the knee, hip, and ankle, 20.6%, 18.5%, and 13.8% respectively. The reject rate is at least as high as the deletion rate and is comparable with previous film-based imaging systems. The reasons for rejection are quite different in digital systems. This falsifies the hypothesis that digitalization would eliminates rejects. A deleted image does not contribute to diagnostics, and therefore is an unnecessary image. Hence, the high rates of deleted images have implications for management, training, education, as well as for quality.

Teknik Pengolahan Citra Digital Berdomain Spasial untuk Peningkatan Citra Sinar-X

Directory of Open Access Journals (Sweden)

Diah Priyawati

2017-01-01

Full Text Available In line with the growing use of computers in medicine, the perceived needs of the image data in digital format. The digital format allows for storage of image data in the computer and processes for further image analysis. Available images today are analog images, the necessary process of digitization with digitizer equipment.The image obtained is not necessarily as expected. Supporting equipment, film, and the scanner has a part in creating the image.Quality of image enhancement is needed to create a quality image allows physicians in diagnosing and minimize the possibility of error analysis.  One of the digital image processing techniques is improving the quality of the image (image enhancement. This is done to obtain a good image after a loss of quality during the process of digitizing the image. Image enhancement techniques are divided into two parts. They are spatial domain and frequency domain. This study uses the spatial domain technique which consists of two stages, such as point operation and mask operation. Image experiments performed with several samples such as thorak, collar bone, bone, body tissue, and the image of the hand. Some sample images have different characteristics but the process of image enhancement have in common that will be improving the image brightness.  Combining the methods of image enhancement performed to get the final digital image that has good qualities, such as histogram function,sharpen function, and continued with the function of a negative image. The final result of the digital image after processing showed that the better image quality.

Natural-pose hand detection in low-resolution images

Directory of Open Access Journals (Sweden)

Nyan Bo Bo1

2009-07-01

Full Text Available Robust real-time hand detection and tracking in video sequences would enable many applications in areas as diverse ashuman-computer interaction, robotics, security and surveillance, and sign language-based systems. In this paper, we introducea new approach for detecting human hands that works on single, cluttered, low-resolution images. Our prototype system, whichis primarily intended for security applications in which the images are noisy and low-resolution, is able to detect hands as smallas 2424 pixels in cluttered scenes. The system uses grayscale appearance information to classify image sub-windows as eithercontaining or not containing a human hand very rapidly at the cost of a high false positive rate. To improve on the false positiverate of the main classifier without affecting its detection rate, we introduce a post-processor system that utilizes the geometricproperties of skin color blobs. When we test our detector on a test image set containing 106 hands, 92 of those hands aredetected (86.8% detection rate, with an average false positive rate of 1.19 false positive detections per image. The rapiddetection speed, the high detection rate of 86.8%, and the low false positive rate together ensure that our system is useable asthe main detector in a diverse variety of applications requiring robust hand detection and tracking in low-resolution, clutteredscenes.

The use of digital images in pathology.

Science.gov (United States)

Furness, P N

1997-11-01

Digital images are routinely used by the publishing industry, but most diagnostic pathologists are unfamiliar with the technology and its possibilities. This review aims to explain the basic principles of digital image acquisition, storage, manipulation and use, and the possibilities provided not only in research, but also in teaching and in routine diagnostic pathology. Images of natural objects are usually expressed digitally as 'bitmaps'--rectilinear arrays of small dots. The size of each dot can vary, but so can its information content in terms, for example, of colour, greyscale or opacity. Various file formats and compression algorithms are available. Video cameras connected to microscopes are familiar to most pathologists; video images can be converted directly to a digital form by a suitably equipped computer. Digital cameras and scanners are alternative acquisition tools of relevance to pathologists. Once acquired, a digital image can easily be subjected to the digital equivalent of any conventional darkroom manipulation and modern software allows much more flexibility, to such an extent that a new tool for scientific fraud has been created. For research, image enhancement and analysis is an increasingly powerful and affordable tool. Morphometric measurements are, after many predictions, at last beginning to be part of the toolkit of the diagnostic pathologist. In teaching, the potential to create dramatic yet informative presentations is demonstrated daily by the publishing industry; such methods are readily applicable to the classroom. The combination of digital images and the Internet raises many possibilities; for example, instead of seeking one expert diagnostic opinion, one could simultaneously seek the opinion of many, all around the globe. It is inevitable that in the coming years the use of digital images will spread from the laboratory to the medical curriculum and to the whole of diagnostic pathology.

Digital image processing techniques in archaeology

Digital Repository Service at National Institute of Oceanography (India)

Santanam, K.; Vaithiyanathan, R.; Tripati, S.

Digital image processing involves the manipulation and interpretation of digital images with the aid of a computer. This form of remote sensing actually began in the 1960's with a limited number of researchers analysing multispectral scanner data...

Vascular changes of the hand in professional baseball players with emphasis on digital ischemia in catchers.

Science.gov (United States)

Ginn, T Adam; Smith, Adam M; Snyder, Jon R; Koman, L Andrew; Smith, Beth P; Rushing, Julia

2005-07-01

Repetitive trauma to the hand is a concern for baseball players. The present study investigated the effects of repetitive trauma and the prevalence of microvascular pathological changes in the hands of minor league professional baseball players. In contrast to previous investigators, we documented the presence of abnormalities in younger, asymptomatic individuals. Thirty-six baseball players on active minor league rosters underwent a history and physical examination of both hands as well as additional specialized tests, including Doppler ultrasound, a timed Allen test, determination of digital brachial pressure indices, and ring sizing of fingers. Data were compared between gloved hands and throwing hands, hitters and nonhitters, and players at four different positions (catcher [nine subjects], outfielder [seven subjects], infielder [five subjects], and pitcher [fifteen subjects]). Digital brachial indices in the ring fingers of the gloved (p healthy professional baseball players in all positions, with a significantly higher prevalence in catchers, prior to the development of clinically important ischemia. Repetitive trauma resulting from the impact of the baseball also leads to digital hypertrophy in the index finger of the gloved hand of catchers. Gloves currently used by professional catchers do not adequately protect the hand from repetitive trauma.

Digital Images and Globalized Conflict

DEFF Research Database (Denmark)

Blaagaard, Bolette; Mortensen, Mette; Neumayer, Christina

2017-01-01

As the number of digital images of globalized conflicts online grow, critical examination of their impact and consequence is timely. This editorial provides an overview of digital images and globalized conflict as a field of study by discussing regimes of visibility and invisibility, proximity...... and distance, and the multiplicity of images. It engages critically with these interlinking themes as they are addressed in the contributing articles to the Special Issue as well as beyond, asking how genres and tropes are reproduced, how power plays a role in access to images, and how the sheer quantity...... of conflict-related images raise issues of knowledge production and research....

Utility of Digital Stereo Images for Optic Disc Evaluation

Science.gov (United States)

Ying, Gui-shuang; Pearson, Denise J.; Bansal, Mayank; Puri, Manika; Miller, Eydie; Alexander, Judith; Piltz-Seymour, Jody; Nyberg, William; Maguire, Maureen G.; Eledath, Jayan; Sawhney, Harpreet

2010-01-01

Purpose. To assess the suitability of digital stereo images for optic disc evaluations in glaucoma. Methods. Stereo color optic disc images in both digital and 35-mm slide film formats were acquired contemporaneously from 29 subjects with various cup-to-disc ratios (range, 0.26–0.76; median, 0.475). Using a grading scale designed to assess image quality, the ease of visualizing optic disc features important for glaucoma diagnosis, and the comparative diameters of the optic disc cup, experienced observers separately compared the primary digital stereo images to each subject's 35-mm slides, to scanned images of the same 35-mm slides, and to grayscale conversions of the digital images. Statistical analysis accounted for multiple gradings and comparisons and also assessed image formats under monoscopic viewing. Results. Overall, the quality of primary digital color images was judged superior to that of 35-mm slides (P digital color images were mostly equivalent to the scanned digitized images of the same slides. Color seemingly added little to grayscale optic disc images, except that peripapillary atrophy was best seen in color (P digital over film images was maintained under monoscopic viewing conditions. Conclusions. Digital stereo optic disc images are useful for evaluating the optic disc in glaucoma and allow the application of advanced image processing applications. Grayscale images, by providing luminance distinct from color, may be informative for assessing certain features. PMID:20505199

HD Photo: a new image coding technology for digital photography

Science.gov (United States)

Srinivasan, Sridhar; Tu, Chengjie; Regunathan, Shankar L.; Sullivan, Gary J.

2007-09-01

This paper introduces the HD Photo coding technology developed by Microsoft Corporation. The storage format for this technology is now under consideration in the ITU-T/ISO/IEC JPEG committee as a candidate for standardization under the name JPEG XR. The technology was developed to address end-to-end digital imaging application requirements, particularly including the needs of digital photography. HD Photo includes features such as good compression capability, high dynamic range support, high image quality capability, lossless coding support, full-format 4:4:4 color sampling, simple thumbnail extraction, embedded bitstream scalability of resolution and fidelity, and degradation-free compressed domain support of key manipulations such as cropping, flipping and rotation. HD Photo has been designed to optimize image quality and compression efficiency while also enabling low-complexity encoding and decoding implementations. To ensure low complexity for implementations, the design features have been incorporated in a way that not only minimizes the computational requirements of the individual components (including consideration of such aspects as memory footprint, cache effects, and parallelization opportunities) but results in a self-consistent design that maximizes the commonality of functional processing components.

Imagers for digital still photography

Science.gov (United States)

Bosiers, Jan; Dillen, Bart; Draijer, Cees; Manoury, Erik-Jan; Meessen, Louis; Peters, Inge

2006-04-01

This paper gives an overview of the requirements for, and current state-of-the-art of, CCD and CMOS imagers for use in digital still photography. Four market segments will be reviewed: mobile imaging, consumer "point-and-shoot cameras", consumer digital SLR cameras and high-end professional camera systems. The paper will also present some challenges and innovations with respect to packaging, testing, and system integration.

ANALYSIS OF THE EFFECTS OF IMAGE QUALITY ON DIGITAL MAP GENERATION FROM SATELLITE IMAGES

Directory of Open Access Journals (Sweden)

H. Kim

2012-07-01

Full Text Available High resolution satellite images are widely used to produce and update a digital map since they became widely available. It is well known that the accuracy of digital map produced from satellite images is decided largely by the accuracy of geometric modelling. However digital maps are made by a series of photogrammetric workflow. Therefore the accuracy of digital maps are also affected by the quality of satellite images, such as image interpretability. For satellite images, parameters such as Modulation Transfer Function(MTF, Signal to Noise Ratio(SNR and Ground Sampling Distance(GSD are used to present images quality. Our previous research stressed that such quality parameters may not represent the quality of image products such as digital maps and that parameters for image interpretability such as Ground Resolved Distance(GRD and National Imagery Interpretability Rating Scale(NIIRS need to be considered. In this study, we analyzed the effects of the image quality on accuracy of digital maps produced by satellite images. QuickBird, IKONOS and KOMPSAT-2 imagery were used to analyze as they have similar GSDs. We measured various image quality parameters mentioned above from these images. Then we produced digital maps from the images using a digital photogrammetric workstation. We analyzed the accuracy of the digital maps in terms of their location accuracy and their level of details. Then we compared the correlation between various image quality parameters and the accuracy of digital maps. The results of this study showed that GRD and NIIRS were more critical for map production then GSD, MTF or SNR.

Image Acquisition and Quality in Digital Radiography.

Science.gov (United States)

Alexander, Shannon

2016-09-01

Medical imaging has undergone dramatic changes and technological breakthroughs since the introduction of digital radiography. This article presents information on the development of digital radiography and types of digital radiography systems. Aspects of image quality and radiation exposure control are highlighted as well. In addition, the article includes related workplace changes and medicolegal considerations in the digital radiography environment. ©2016 American Society of Radiologic Technologists.

Image processing by use of the digital cross-correlator

International Nuclear Information System (INIS)

Katou, Yoshinori

1982-01-01

We manufactured for trial an instrument which achieved the image processing using digital correlators. A digital correlator perform 64-bit parallel correlation at 20 MH. The output of a digital correlator is a 7-bit word representing. An A-D converter is used to quantize it a precision of six bits. The resulting 6-bit word is fed to six correlators, wired in parallel. The image processing achieved in 12 bits, whose digital outputs converted an analog signal by a D-A converter. This instrument is named the digital cross-correlator. The method which was used in the image processing system calculated the convolution with the digital correlator. It makes various digital filters. In the experiment with the image processing video signals from TV camera were used. The digital image processing time was approximately 5 μs. The contrast was enhanced and smoothed. The digital cross-correlator has the image processing of 16 sorts, and was produced inexpensively. (author)

Digital color imaging

CERN Document Server

Fernandez-Maloigne, Christine; Macaire, Ludovic

2013-01-01

This collective work identifies the latest developments in the field of the automatic processing and analysis of digital color images.For researchers and students, it represents a critical state of the art on the scientific issues raised by the various steps constituting the chain of color image processing.It covers a wide range of topics related to computational color imaging, including color filtering and segmentation, color texture characterization, color invariant for object recognition, color and motion analysis, as well as color image and video indexing and retrieval. <

Digital image processing

National Research Council Canada - National Science Library

Gonzalez, Rafael C; Woods, Richard E

2008-01-01

Completely self-contained-and heavily illustrated-this introduction to basic concepts and methodologies for digital image processing is written at a level that truly is suitable for seniors and first...

3D palmprint and hand imaging system based on full-field composite color sinusoidal fringe projection technique.

Science.gov (United States)

Zhang, Zonghua; Huang, Shujun; Xu, Yongjia; Chen, Chao; Zhao, Yan; Gao, Nan; Xiao, Yanjun

2013-09-01

Palmprint and hand shape, as two kinds of important biometric characteristics, have been widely studied and applied to human identity recognition. The existing research is based mainly on 2D images, which lose the third-dimensional information. The biological features extracted from 2D images are distorted by pressure and rolling, so the subsequent feature matching and recognition are inaccurate. This paper presents a method to acquire accurate 3D shapes of palmprint and hand by projecting full-field composite color sinusoidal fringe patterns and the corresponding color texture information. A 3D imaging system is designed to capture and process the full-field composite color fringe patterns on hand surface. Composite color fringe patterns having the optimum three fringe numbers are generated by software and projected onto the surface of human hand by a digital light processing projector. From another viewpoint, a color CCD camera captures the deformed fringe patterns and saves them for postprocessing. After compensating for the cross talk and chromatic aberration between color channels, three fringe patterns are extracted from three color channels of a captured composite color image. Wrapped phase information can be calculated from the sinusoidal fringe patterns with high precision. At the same time, the absolute phase of each pixel is determined by the optimum three-fringe selection method. After building up the relationship between absolute phase map and 3D shape data, the 3D palmprint and hand are obtained. Color texture information can be directly captured or demodulated from the captured composite fringe pattern images. Experimental results show that the proposed method and system can yield accurate 3D shape and color texture information of the palmprint and hand shape.

Digital imaging in conventional diagnostic radiology: status and trends

International Nuclear Information System (INIS)

Pfeiler, M.; Marhoff, P.; Schipper, P.

1984-01-01

Digital techniques, i.e. techniques using microcomputers of minicomputers, are getting increasingly common in so-called conventional radiography. These nonreconstructive techniques are referred to here as 'digital, direct-imaging radiography' in order to contrast them with the reconstructive techniques of computerized tomography. Digitalisation of imaging and image processing operation and control will change the jobs of the radiologist and radiological assistants in such manner that only X-ray units with film-foil systems or with X-ray image intensification should be classified as conventional systems. Digital and conventional systems differ in that digital techniques imply the possibility of establishing data pools which may eventually be developed into a digital image interconnection and archiving system. The authors first describe the general system in which the digital imaging systems must be integrated on a medium-term and long-term basis and then proceed to discuss digital imaging and image processing in some more detail. (orig./WU) [de

Incidence of Apical Crack Initiation during Canal Preparation using Hand Stainless Steel (K-File) and Hand NiTi (Protaper) Files.

Science.gov (United States)

Soni, Dileep; Raisingani, Deepak; Mathur, Rachit; Madan, Nidha; Visnoi, Suchita

2016-01-01

To evaluate the incidence of apical crack initiation during canal preparation with stainless steel K-files and hand protaper files (in vitro study). Sixty extracted mandibular premo-lar teeth are randomly selected and embedded in an acrylic tube filled with autopolymerizing resin. A baseline image of the apical surface of each specimen was recorded under a digital microscope (80×). The cervical and middle thirds of all samples were flared with #2 and #1 Gates-Glidden (GG) drills, and a second image was recorded. The teeth were randomly divided into four groups of 15 teeth each according to the file type (hand K-file and hand-protaper) and working length (WL) (instrumented at WL and 1 mm less than WL). Final image after dye penetration and photomicrograph of the apical root surface were digitally recorded. Maximum numbers of cracks were observed with hand protaper files compared with hand K-file at the WL and 1 mm short of WL. Chi-square testing revealed a highly significant effect of WL on crack formation at WL and 1 mm short of WL (p = 0.000). Minimum numbers of cracks at WL and 1 mm short of WL were observed with hand K-file and maximum with hand protaper files. Soni D, Raisingani D, Mathur R, Madan N, Visnoi S. Incidence of Apical Crack Initiation during Canal Preparation using Hand Stainless Steel (K-File) and Hand NiTi (Protaper) Files. Int J Clin Pediatr Dent 2016;9(4):303-307.

Development and evaluation of a hand tracker using depth images captured from an overhead perspective.

Science.gov (United States)

Czarnuch, Stephen; Mihailidis, Alex

2015-03-27

We present the development and evaluation of a robust hand tracker based on single overhead depth images for use in the COACH, an assistive technology for people with dementia. The new hand tracker was designed to overcome limitations experienced by the COACH in previous clinical trials. We train a random decision forest classifier using ∼5000 manually labeled, unbalanced, training images. Hand positions from the classifier are translated into task actions based on proximity to environmental objects. Tracker performance is evaluated using a large set of ∼24 000 manually labeled images captured from 41 participants in a fully-functional washroom, and compared to the system's previous colour-based hand tracker. Precision and recall were 0.994 and 0.938 for the depth tracker compared to 0.981 and 0.822 for the colour tracker with the current data, and 0.989 and 0.466 in the previous study. The improved tracking performance supports integration of the depth-based tracker into the COACH toward unsupervised, real-world trials. Implications for Rehabilitation The COACH is an intelligent assistive technology that can enable people with cognitive disabilities to stay at home longer, supporting the concept of aging-in-place. Automated prompting systems, a type of intelligent assistive technology, can help to support the independent completion of activities of daily living, increasing the independence of people with cognitive disabilities while reducing the burden of care experienced by caregivers. Robust motion tracking using depth imaging supports the development of intelligent assistive technologies like the COACH. Robust motion tracking also has application to other forms of assistive technologies including gaming, human-computer interaction and automated assessments.

How Digital Image Processing Became Really Easy

Science.gov (United States)

Cannon, Michael

1988-02-01

In the early and mid-1970s, digital image processing was the subject of intense university and corporate research. The research lay along two lines: (1) developing mathematical techniques for improving the appearance of or analyzing the contents of images represented in digital form, and (2) creating cost-effective hardware to carry out these techniques. The research has been very effective, as evidenced by the continued decline of image processing as a research topic, and the rapid increase of commercial companies to market digital image processing software and hardware.

Digital medical imaging

International Nuclear Information System (INIS)

Goeringer, F.; Mun, S.K.; Kerlin, B.D.

1989-01-01

In formulating an implementation strategy for digital medical imaging, three interrelated thrusts have emerged for the defense medical establishment. These thrusts: totally filmless medical imaging on the battlefield, teleradiology, and DIN/PACS for peacetime military health care are discussed. They have implications in their fully developed form as resource savers and quality improvers for the unique aspects of military health care

Edge-detect interpolation for direct digital periapical images

International Nuclear Information System (INIS)

Song, Nam Kyu; Koh, Kwang Joon

1998-01-01

The purpose of this study was to aid in the use of the digital images by edge-detect interpolation for direct digital periapical images using edge-deted interpolation. This study was performed by image processing of 20 digital periapical images; pixel replication, linear non-interpolation, linear interpolation, and edge-sensitive interpolation. The obtained results were as follows ; 1. Pixel replication showed blocking artifact and serious image distortion. 2. Linear interpolation showed smoothing effect on the edge. 3. Edge-sensitive interpolation overcame the smoothing effect on the edge and showed better image.

Digital repeat analysis; setup and operation.

Science.gov (United States)

Nol, J; Isouard, G; Mirecki, J

2006-06-01

Since the emergence of digital imaging, there have been questions about the necessity of continuing reject analysis programs in imaging departments to evaluate performance and quality. As a marketing strategy, most suppliers of digital technology focus on the supremacy of the technology and its ability to reduce the number of repeats, resulting in less radiation doses given to patients and increased productivity in the department. On the other hand, quality assurance radiographers and radiologists believe that repeats are mainly related to positioning skills, and repeat analysis is the main tool to plan training needs to up-skill radiographers. A comparative study between conventional and digital imaging was undertaken to compare outcomes and evaluate the need for reject analysis. However, digital technology still being at its early development stages, setting a credible reject analysis program became the major task of the study. It took the department, with the help of the suppliers of the computed radiography reader and the picture archiving and communication system, over 2 years of software enhancement to build a reliable digital repeat analysis system. The results were supportive of both philosophies; the number of repeats as a result of exposure factors was reduced dramatically; however, the percentage of repeats as a result of positioning skills was slightly on the increase for the simple reason that some rejects in the conventional system qualifying for both exposure and positioning errors were classified as exposure error. The ability of digitally adjusting dark or light images reclassified some of those images as positioning errors.

Digital Imaging: An Adobe Photoshop Course

Science.gov (United States)

Cobb, Kristine

2007-01-01

This article introduces digital imaging, an Adobe Photoshop course at Shrewsbury High School in Shrewsbury, Massachusetts. Students are able to earn art credits to graduate by successfully completing the course. Digital imaging must cover art criteria as well as technical skills. The course begins with tutorials created by the instructor and other…

Standard digital reference images for titanium castings

CERN Document Server

American Society for Testing and Materials. Philadelphia

2010-01-01

1.1 The digital reference images provided in the adjunct to this standard illustrate various types and degrees of discontinuities occurring in titanium castings. Use of this standard for the specification or grading of castings requires procurement of the adjunct digital reference images, which illustrate the discontinuity types and severity levels. They are intended to provide the following: 1.1.1 A guide enabling recognition of titanium casting discontinuities and their differentiation both as to type and degree through digital radiographic examination. 1.1.2 Example digital radiographic illustrations of discontinuities and a nomenclature for reference in acceptance standards, specifications and drawings. 1.2 The digital reference images consist of seventeen digital files each illustrating eight grades of increasing severity. The files illustrate seven common discontinuity types representing casting sections up to 1-in. (25.4-mm). 1.3 The reference radiographs were developed for casting sections up to 1...

Digital image processing mathematical and computational methods

CERN Document Server

Blackledge, J M

2005-01-01

This authoritative text (the second part of a complete MSc course) provides mathematical methods required to describe images, image formation and different imaging systems, coupled with the principle techniques used for processing digital images. It is based on a course for postgraduates reading physics, electronic engineering, telecommunications engineering, information technology and computer science. This book relates the methods of processing and interpreting digital images to the 'physics' of imaging systems. Case studies reinforce the methods discussed, with examples of current research

Securing Digital Images Integrity using Artificial Neural Networks

Science.gov (United States)

Hajji, Tarik; Itahriouan, Zakaria; Ouazzani Jamil, Mohammed

2018-05-01

Digital image signature is a technique used to protect the image integrity. The application of this technique can serve several areas of imaging applied to smart cities. The objective of this work is to propose two methods to protect digital image integrity. We present a description of two approaches using artificial neural networks (ANN) to digitally sign an image. The first one is “Direct Signature without learning” and the second is “Direct Signature with learning”. This paper presents the theory of proposed approaches and an experimental study to test their effectiveness.

The Digital Microscope and Its Image Processing Utility

Directory of Open Access Journals (Sweden)

Tri Wahyu Supardi

2011-12-01

Full Text Available Many institutions, including high schools, own a large number of analog or ordinary microscopes. These microscopes are used to observe small objects. Unfortunately, object observations on the ordinary microscope require precision and visual acuity of the user. This paper discusses the development of a high-resolution digital microscope from an analog microscope, including the image processing utility, which allows the digital microscope users to capture, store and process the digital images of the object being observed. The proposed microscope is constructed from hardware components that can be easily found in Indonesia. The image processing software is capable of performing brightness adjustment, contrast enhancement, histogram equalization, scaling and cropping. The proposed digital microscope has a maximum magnification of 1600x, and image resolution can be varied from 320x240 pixels up to 2592x1944 pixels. The microscope was tested with various objects with a variety of magnification, and image processing was carried out on the image of the object. The results showed that the digital microscope and its image processing system were capable of enhancing the observed object and other operations in accordance with the user need. The digital microscope has eliminated the need for direct observation by human eye as with the traditional microscope.

New possibilities of digital luminescence radiography (DLR) and digital image processing for verification and portal imaging

International Nuclear Information System (INIS)

Zimmermann, J.S.; Blume, J.; Wendhausen, H.; Hebbinghaus, D.; Kovacs, G.; Eilf, K.; Schultze, J.; Kimmig, B.N.

1995-01-01

We developed a method, using digital luminescence radiography (DLR), not only for portal imaging of photon beams in an excellent quality, but also for verification of electron beams. Furtheron, DLR was used as basic instrument for image fusion of portal and verification film and simulation film respectively for image processing in ''beams-eye-view'' verification (BEVV) of rotating beams or conformation therapy. Digital radiographs of an excellent quality are gained for verification of photon and electron beams. In photon beams, quality improvement vs. conventional portal imaging may be dramatic, even more for high energy beams (e.g. 15-MV-photon beams) than for Co-60. In electron beams, excellent results may be easily obtained. By digital image fusion of 1 or more verification films on simulation film or MRI-planning film, more precise judgement even on small differences between simulation and verification films becomes possible. Using BEVV, it is possible to compare computer aided simulation in rotating beams or conformation therapy with the really applied treatment. The basic principle of BEVV is also suitable for dynamic multileaf collimation. (orig.) [de

Losing Images in Digital Radiology: More than You Think

OpenAIRE

Oglevee, Catherine; Pianykh, Oleg

2014-01-01

It is a common belief that the shift to digital imaging some 20 years ago helped medical image exchange and got rid of any potential image loss that was happening with printed image films. Unfortunately, this is not the case: despite the most recent advances in digital imaging, most hospitals still keep losing their imaging data, with these losses going completely unnoticed. As a result, not only does image loss affect the faith in digital imaging but it also affects patient diagnosis and dai...

Detection and optimization of image quality and dose in digital mammography systems

International Nuclear Information System (INIS)

Semturs, F.

2015-01-01

Background and purpose: During the last few years, mammography institutes have replaced their conventional mammography systems (FSM) with digital mammography systems (FFDM). This happened mainly in direction to digital computed radiography systems (FFDM-CR), where the mammography device could be kept in operation. Consequently also the AEC-parameters have not been changed and therefore the same dose as for FFM was used. Following the main theme of the thesis "Optimization of image quality and dose", also measurements with such CR-Systems have been performed in relation to image quality and dose behavior. Optimization in this context means - in following the ALARA principle - the reduction of dose while ensuring required clinical image quality. With other words - image quality is of higher value compared to dose. Considering this, it has been found out through measurements during this thesis, that FFDM-CR Systems need considerable more dose for achieving image quality comparable with FFM. On the other hand, it has been shown with measurements during this thesis, that the newest FFDM-CR technology (needle structure) supports dose reduction (optimization) to a certain degree without compromising image quality. Dose increase, as recommended in this thesis, could also increase the danger of more radiation induced carcinoma. There are several studies (which are also discussed in this thesis), which show that the benefit of not missing cancers because of higher dose dramatically overrides any health concerns. Such an optimization of image quality and dose is now described in more detail by comparing the new CR needle technology with the older power based CR technology. Material and Methods: The image quality and dose behavior for multiple breast thicknesses (simulated with PMMA slabs) of a CR needle crystal detector system is optimized by considering also different beam qualities. Technical image quality is determined with a low contrast phantom (CDMAM phantom) and from

The impact of digital imaging in the field of cytopathology.

Science.gov (United States)

Pantanowitz, Liron; Hornish, Maryanne; Goulart, Robert A

2009-03-06

With the introduction of digital imaging, pathology is undergoing a digital transformation. In the field of cytology, digital images are being used for telecytology, automated screening of Pap test slides, training and education (e.g. online digital atlases), and proficiency testing. To date, there has been no systematic review on the impact of digital imaging on the practice of cytopathology. This article critically addresses the emerging role of computer-assisted screening and the application of digital imaging to the field of cytology, including telecytology, virtual microscopy, and the impact of online cytology resources. The role of novel diagnostic techniques like image cytometry is also reviewed.

Camac interface for digitally recording infrared camera images

International Nuclear Information System (INIS)

Dyer, G.R.

1986-01-01

An instrument has been built to store the digital signals from a modified imaging infrared scanner directly in a digital memory. This procedure avoids the signal-to-noise degradation and dynamic range limitations associated with successive analog-to-digital and digital-to-analog conversions and the analog recording method normally used to store data from the scanner. This technique also allows digital data processing methods to be applied directly to recorded data and permits processing and image reconstruction to be done using either a mainframe or a microcomputer. If a suitable computer and CAMAC-based data collection system are already available, digital storage of up to 12 scanner images can be implemented for less than $1750 in materials cost. Each image is stored as a frame of 60 x 80 eight-bit pixels, with an acquisition rate of one frame every 16.7 ms. The number of frames stored is limited only by the available memory. Initially, data processing for this equipment was done on a VAX 11-780, but images may also be displayed on the screen of a microcomputer. Software for setting the displayed gray scale, generating contour plots and false-color displays, and subtracting one image from another (e.g., background suppression) has been developed for IBM-compatible personal computers

Computing Hypercrossed Complex Pairings in Digital Images

Directory of Open Access Journals (Sweden)

Simge Öztunç

2013-01-01

Full Text Available We consider an additive group structure in digital images and introduce the commutator in digital images. Then we calculate the hypercrossed complex pairings which generates a normal subgroup in dimension 2 and in dimension 3 by using 8-adjacency and 26-adjacency.

Radiological imaging of congenital hand anomalies - a 6-year single-centre experience and what the hand surgeons want to know

International Nuclear Information System (INIS)

Gerety, E.L.; Hopper, M.A.; Grant, I.

2015-01-01

Congenital hand anomalies present a rare but important physical and emotional challenge for children and parents. Radiological imaging is important for accurate diagnosis, to aid decision making and to monitor changes in the growing hand. The goal of any treatment is to help the child achieve his/her maximum potential, to provide a useful hand with attention to cosmesis. We investigated the range of congenital hand anomalies imaged in a tertiary referral centre. We examined the timing of imaging and the key clinical questions. The radiology imaging system was searched retrospectively for radiographs of congenital hand anomalies over a 6-year period. The images were reviewed and patient demographics, diagnosis and other imaging recorded. Over 6 years, 85 patients had imaging. Twenty-three patients had bilateral problems and 11 had recognised syndromes. The most common abnormalities imaged were duplicated thumbs (28 %), followed by syndactyly (18 %). Children were first imaged as early as 1 day old, with the median age of initial imaging 12 months. Thumb duplication and syndactyly are the most common conditions for which radiographs are requested at our hospital, although overall syndactyly is considered the most common congenital hand anomaly. For a variety of reasons, children are often imaged very early, before review by the Specialist in Children's Hand Surgery (despite surgery being unlikely before 1 year of age.) We discuss the classification systems and specific issues that hand surgeons want to know from the radiologists. (orig.)

Radiological imaging of congenital hand anomalies - a 6-year single-centre experience and what the hand surgeons want to know

Energy Technology Data Exchange (ETDEWEB)

Gerety, E.L.; Hopper, M.A. [Cambridge University Hospitals NHS Foundation Trust, Department of Radiology, Cambridge (United Kingdom); Grant, I. [Cambridge University Hospitals NHS Foundation Trust, Department of Plastic Surgery, Cambridge (United Kingdom)

2014-12-19

Congenital hand anomalies present a rare but important physical and emotional challenge for children and parents. Radiological imaging is important for accurate diagnosis, to aid decision making and to monitor changes in the growing hand. The goal of any treatment is to help the child achieve his/her maximum potential, to provide a useful hand with attention to cosmesis. We investigated the range of congenital hand anomalies imaged in a tertiary referral centre. We examined the timing of imaging and the key clinical questions. The radiology imaging system was searched retrospectively for radiographs of congenital hand anomalies over a 6-year period. The images were reviewed and patient demographics, diagnosis and other imaging recorded. Over 6 years, 85 patients had imaging. Twenty-three patients had bilateral problems and 11 had recognised syndromes. The most common abnormalities imaged were duplicated thumbs (28 %), followed by syndactyly (18 %). Children were first imaged as early as 1 day old, with the median age of initial imaging 12 months. Thumb duplication and syndactyly are the most common conditions for which radiographs are requested at our hospital, although overall syndactyly is considered the most common congenital hand anomaly. For a variety of reasons, children are often imaged very early, before review by the Specialist in Children's Hand Surgery (despite surgery being unlikely before 1 year of age.) We discuss the classification systems and specific issues that hand surgeons want to know from the radiologists. (orig.)

Estimation of breast percent density in raw and processed full field digital mammography images via adaptive fuzzy c-means clustering and support vector machine segmentation

International Nuclear Information System (INIS)

Keller, Brad M.; Nathan, Diane L.; Wang Yan; Zheng Yuanjie; Gee, James C.; Conant, Emily F.; Kontos, Despina

2012-01-01

Purpose: The amount of fibroglandular tissue content in the breast as estimated mammographically, commonly referred to as breast percent density (PD%), is one of the most significant risk factors for developing breast cancer. Approaches to quantify breast density commonly focus on either semiautomated methods or visual assessment, both of which are highly subjective. Furthermore, most studies published to date investigating computer-aided assessment of breast PD% have been performed using digitized screen-film mammograms, while digital mammography is increasingly replacing screen-film mammography in breast cancer screening protocols. Digital mammography imaging generates two types of images for analysis, raw (i.e., “FOR PROCESSING”) and vendor postprocessed (i.e., “FOR PRESENTATION”), of which postprocessed images are commonly used in clinical practice. Development of an algorithm which effectively estimates breast PD% in both raw and postprocessed digital mammography images would be beneficial in terms of direct clinical application and retrospective analysis. Methods: This work proposes a new algorithm for fully automated quantification of breast PD% based on adaptive multiclass fuzzy c-means (FCM) clustering and support vector machine (SVM) classification, optimized for the imaging characteristics of both raw and processed digital mammography images as well as for individual patient and image characteristics. Our algorithm first delineates the breast region within the mammogram via an automated thresholding scheme to identify background air followed by a straight line Hough transform to extract the pectoral muscle region. The algorithm then applies adaptive FCM clustering based on an optimal number of clusters derived from image properties of the specific mammogram to subdivide the breast into regions of similar gray-level intensity. Finally, a SVM classifier is trained to identify which clusters within the breast tissue are likely fibroglandular, which

Steganography and Steganalysis in Digital Images

Science.gov (United States)

2012-01-01

REPORT Steganography and Steganalysis in Digital Images 14. ABSTRACT 16. SECURITY CLASSIFICATION OF: Steganography (from the Greek for "covered writing...12211 Research Triangle Park, NC 27709-2211 15. SUBJECT TERMS Least Significant Bit ( LSB ), steganography , steganalysis, stegogramme. Dr. Jeff Duffany...Z39.18 - Steganography and Steganalysis in Digital Images Report Title ABSTRACT Steganography (from the Greek for "covered writing") is the secret

Topology of digital images visual pattern discovery in proximity spaces

CERN Document Server

Peters, James F

2014-01-01

This book carries forward recent work on visual patterns and structures in digital images and introduces a near set-based a topology of digital images. Visual patterns arise naturally in digital images viewed as sets of non-abstract points endowed with some form of proximity (nearness) relation. Proximity relations make it possible to construct uniform topolo- gies on the sets of points that constitute a digital image. In keeping with an interest in gaining an understanding of digital images themselves as a rich source of patterns, this book introduces the basics of digital images from a computer vision perspective. In parallel with a computer vision perspective on digital images, this book also introduces the basics of prox- imity spaces. Not only the traditional view of spatial proximity relations but also the more recent descriptive proximity relations are considered. The beauty of the descriptive proximity approach is that it is possible to discover visual set patterns among sets that are non-overlapping ...

A biometric authentication model using hand gesture images.

Science.gov (United States)

Fong, Simon; Zhuang, Yan; Fister, Iztok; Fister, Iztok

2013-10-30

A novel hand biometric authentication method based on measurements of the user's stationary hand gesture of hand sign language is proposed. The measurement of hand gestures could be sequentially acquired by a low-cost video camera. There could possibly be another level of contextual information, associated with these hand signs to be used in biometric authentication. As an analogue, instead of typing a password 'iloveu' in text which is relatively vulnerable over a communication network, a signer can encode a biometric password using a sequence of hand signs, 'i' , 'l' , 'o' , 'v' , 'e' , and 'u'. Subsequently the features from the hand gesture images are extracted which are integrally fuzzy in nature, to be recognized by a classification model for telling if this signer is who he claimed himself to be, by examining over his hand shape and the postures in doing those signs. It is believed that everybody has certain slight but unique behavioral characteristics in sign language, so are the different hand shape compositions. Simple and efficient image processing algorithms are used in hand sign recognition, including intensity profiling, color histogram and dimensionality analysis, coupled with several popular machine learning algorithms. Computer simulation is conducted for investigating the efficacy of this novel biometric authentication model which shows up to 93.75% recognition accuracy.

Effects of optimization and image processing in digital chest radiography

International Nuclear Information System (INIS)

Kheddache, S.; Maansson, L.G.; Angelhed, J.E.; Denbratt, L.; Gottfridsson, B.; Schlossman, D.

1991-01-01

A digital system for chest radiography based on a large image intensifier was compared to a conventional film-screen system. The digital system was optimized with regard to spatial and contrast resolution and dose. The images were digitally processed for contrast and edge enhancement. A simulated pneumothorax and two and two simulated nodules were positioned over the lungs and the mediastinum of an anthro-pomorphic phantom. Observer performance was evaluated with Receiver Operating Characteristic (ROC) analysis. Five observers assessed the processed digital images and the conventional full-size radiographs. The time spent viewing the full-size radiographs and the digital images was recorded. For the simulated pneumothorax, the results showed perfect performance for the full-size radiographs and detectability was high also for the processed digital images. No significant differences in the detectability of the simulated nodules was seen between the two imaging systems. The results for the digital images showed a significantly improved detectability for the nodules in the mediastinum as compared to a previous ROC study where no optimization and image processing was available. No significant difference in detectability was seen between the former and the present ROC study for small nodules in the lung. No difference was seen in the time spent assessing the conventional full-size radiographs and the digital images. The study indicates that processed digital images produced by a large image intensifier are equal in image quality to conventional full-size radiographs for low-contrast objects such as nodules. (author). 38 refs.; 4 figs.; 1 tab

A Preliminary Comparison of Three Dimensional Particle Tracking and Sizing using Plenoptic Imaging and Digital In-line Holography

Energy Technology Data Exchange (ETDEWEB)

Guildenbecher, Daniel Robert; Munz, Elise Dahnke; Farias, Paul Abraham; Thurow, Brian S [Auburn U

2015-12-01

Digital in-line holography and plenoptic photography are two techniques for single-shot, volumetric measurement of 3D particle fields. Here we present a preliminary comparison of the two methods by applying plenoptic imaging to experimental configurations that have been previously investigated with digital in-line holography. These experiments include the tracking of secondary droplets from the impact of a water drop on a thin film of water and tracking of pellets from a shotgun. Both plenoptic imaging and digital in-line holography successfully quantify the 3D nature of these particle fields. This includes measurement of the 3D particle position, individual particle sizes, and three-component velocity vectors. For the initial processing methods presented here, both techniques give out-of-plane positional accuracy of approximately 1-2 particle diameters. For a fixed image sensor, digital holography achieves higher effective in-plane spatial resolutions. However, collimated and coherent illumination makes holography susceptible to image distortion through index of refraction gradients, as demonstrated in the shotgun experiments. On the other hand, plenotpic imaging allows for a simpler experimental configuration. Furthermore, due to the use of diffuse, white-light illumination, plenoptic imaging is less susceptible to image distortion in the shotgun experiments. Additional work is needed to better quantify sources of uncertainty, particularly in the plenoptic experiments, as well as develop data processing methodologies optimized for the plenoptic measurement.

Existential space understanding through digital image

Directory of Open Access Journals (Sweden)

Susana Iñarra Abad

2013-10-01

Full Text Available The logical way to learn from the architectural space and then be able to design and represent it is, undoubtedly, that of experiencing it through all the sensitive channels that the space wakes up us.  But since the last 30 years, much of our learning about space comes from images of architecture and not from the space itself. The art of architecture is drifting towards a visual art and moving away from its existential side. In digital images that have flooded the architectural media, digital photographs of existing spaces intermingle with non-existent space renderings (photographs with a virtual camera. The first ones represent existing places but can be altered to change the perception that  the observer of the image will have, the second ones speak to us about places that do not exist yet but they present reality portions through extracts from digital photography (textures, trees, people... that compose the image.

Integrated optical 3D digital imaging based on DSP scheme

Science.gov (United States)

Wang, Xiaodong; Peng, Xiang; Gao, Bruce Z.

2008-03-01

We present a scheme of integrated optical 3-D digital imaging (IO3DI) based on digital signal processor (DSP), which can acquire range images independently without PC support. This scheme is based on a parallel hardware structure with aid of DSP and field programmable gate array (FPGA) to realize 3-D imaging. In this integrated scheme of 3-D imaging, the phase measurement profilometry is adopted. To realize the pipeline processing of the fringe projection, image acquisition and fringe pattern analysis, we present a multi-threads application program that is developed under the environment of DSP/BIOS RTOS (real-time operating system). Since RTOS provides a preemptive kernel and powerful configuration tool, with which we are able to achieve a real-time scheduling and synchronization. To accelerate automatic fringe analysis and phase unwrapping, we make use of the technique of software optimization. The proposed scheme can reach a performance of 39.5 f/s (frames per second), so it may well fit into real-time fringe-pattern analysis and can implement fast 3-D imaging. Experiment results are also presented to show the validity of proposed scheme.

Report from the research committee of digital imaging standardization in nuclear medicine

International Nuclear Information System (INIS)

Nakamura, Yutaka; Ise, Toshihide; Isetani, Osamu; Ichihara, Takashi; Ohya, Nobuyoshi; Kanaya, Shinichi; Fukuda, Toshio; Horii, Hitoshi.

1994-01-01

Since digital scintillation camera systems were developed in 1982, digital imaging is rapidly replacing analog imaging. During the first year, the research committee of digital imaging standardization has collected and analyzed basic data concerning digital examination equipment systems, display equipments, films, and hardware and software techniques to determine items required for the standardization of digital imaging. During the second year, it has done basic phantom studies to assess digital images and analyzed the results from both physical and visual viewpoints. On the basis of the outcome of the research committee's activities and the nationwide survey, the draft of digital imaging standardization in nuclear medicine has been presented. In this paper. the analytical data of the two-year survey, made by the research committee of digital imaging standardization, are presented. The descriptions are given under the following four items: (1) standardization digital examination techniques, (2) standardization of display techniques, (3) the count and pixel of digital images, and (4) standardization of digital imaging techniques. (N.K.)

Computer assisted visualization of digital mammography images

International Nuclear Information System (INIS)

Funke, M.; Breiter, N.; Grabbe, E.; Netsch, T.; Biehl, M.; Peitgen, H.O.

1999-01-01

Purpose: In a clinical study, the feasibility of using a mammography workstation for the display and interpretation of digital mammography images was evaluated and the results were compared with the corresponding laser film hard copies. Materials and Methods: Digital phosphorous plate radiographs of the entire breast were obtained in 30 patients using a direct magnification mammography system. The images were displayed for interpretation on the computer monitor of a dedicated mammography workstation and also presented as laser film hard copies on a film view box for comparison. The images were evaluted with respect to the image handling, the image quality and the visualization of relevant structures by 3 readers. Results: Handling and contrast of the monitor displayed images were found to be superior compared with the film hard copies. Image noise was found in some cases but did not compromise the interpretation of the monitor images. The visualization of relevant structures was equal with both modalities. Altogether, image interpretation with the mammography workstation was considered to be easy, quick and confident. Conclusions: Computer-assisted visualization and interpretation of digital mammography images using a dedicated workstation can be performed with sufficiently high diagnostic accuracy. (orig.) [de

Advantages of digital imaging for radiological diagnostic

International Nuclear Information System (INIS)

Trapero, M. A.; Gonzalez, S.; Albillos, J. C.; Martel, J.; Rebollo, M.

2006-01-01

The advantages and limitations of radiological digital images in comparison with analogic ones are analyzed. We discuss three main topics: acquisition, post-procedure manipulation, and visualization, archive and communication. Digital acquisition with computed radiology systems present a global sensitivity very close to conventional film for diagnostic purposes. However, flat panel digital systems seems to achieve some advantages in particular clinical situations. A critical issue is the radiation dose-reduction that can be accomplished without reducing image quality nor diagnostic exactitude. The post-procedure manipulation allows, particularly in multiplanar modalities like CT or MR, to extract all implicit diagnostic information in the images: Main procedures are multiplanar and three-dimensional reformations, dynamic acquisitions, functional studies and image fusion. The use of PACS for visualization, archive and communication of images, improves the effectiveness and the efficiency of the workflow, allows a more comfortable diagnosis for the radiologist and gives way to improvements in the communication of images, allowing tele consulting and the tele radiology. (Author) 6 refs

Structure of the medical digital image

International Nuclear Information System (INIS)

Baltadzhiev, D.

1997-01-01

In up-to-date medical practice diagnostic imaging techniques are the most powerful tools available to clinicians. The modern medical equipment is entirely based on digital technology. In this article the principle of generating medical images is presented. The concept for gray scale where medical images are commonly presented is described. The patterns of gray images transformation into colour scale are likewise outlined. Basic notions from medical imaging terminology such as image matrix, pixel, spatial and contrast resolution power, bit, byte and the like are explained. Also an example is given of how the binary system treats images. On the basis of digital technology the obtained medical images lend themselves readily to additional processing, reconstruction (including 3D) and storage for subsequent utilization. The ceaseless progress of computerized communications promote easy and prompt access for clinicians to the diagnostic images needed as well as realization of expert consultations by teleconference contact (author)

Wrist Hypothermia Related to Continuous Work with a Computer Mouse: A Digital Infrared Imaging Pilot Study

Directory of Open Access Journals (Sweden)

Jelena Reste

2015-08-01

Full Text Available Computer work is characterized by sedentary static workload with low-intensity energy metabolism. The aim of our study was to evaluate the dynamics of skin surface temperature in the hand during prolonged computer mouse work under different ergonomic setups. Digital infrared imaging of the right forearm and wrist was performed during three hours of continuous computer work (measured at the start and every 15 minutes thereafter in a laboratory with controlled ambient conditions. Four people participated in the study. Three different ergonomic computer mouse setups were tested on three different days (horizontal computer mouse without mouse pad; horizontal computer mouse with mouse pad and padded wrist support; vertical computer mouse without mouse pad. The study revealed a significantly strong negative correlation between the temperature of the dorsal surface of the wrist and time spent working with a computer mouse. Hand skin temperature decreased markedly after one hour of continuous computer mouse work. Vertical computer mouse work preserved more stable and higher temperatures of the wrist (>30 °C, while continuous use of a horizontal mouse for more than two hours caused an extremely low temperature (<28 °C in distal parts of the hand. The preliminary observational findings indicate the significant effect of the duration and ergonomics of computer mouse work on the development of hand hypothermia.

eCTG: an automatic procedure to extract digital cardiotocographic signals from digital images.

Science.gov (United States)

Sbrollini, Agnese; Agostinelli, Angela; Marcantoni, Ilaria; Morettini, Micaela; Burattini, Luca; Di Nardo, Francesco; Fioretti, Sandro; Burattini, Laura

2018-03-01

Cardiotocography (CTG), consisting in the simultaneous recording of fetal heart rate (FHR) and maternal uterine contractions (UC), is a popular clinical test to assess fetal health status. Typically, CTG machines provide paper reports that are visually interpreted by clinicians. Consequently, visual CTG interpretation depends on clinician's experience and has a poor reproducibility. The lack of databases containing digital CTG signals has limited number and importance of retrospective studies finalized to set up procedures for automatic CTG analysis that could contrast visual CTG interpretation subjectivity. In order to help overcoming this problem, this study proposes an electronic procedure, termed eCTG, to extract digital CTG signals from digital CTG images, possibly obtainable by scanning paper CTG reports. eCTG was specifically designed to extract digital CTG signals from digital CTG images. It includes four main steps: pre-processing, Otsu's global thresholding, signal extraction and signal calibration. Its validation was performed by means of the "CTU-UHB Intrapartum Cardiotocography Database" by Physionet, that contains digital signals of 552 CTG recordings. Using MATLAB, each signal was plotted and saved as a digital image that was then submitted to eCTG. Digital CTG signals extracted by eCTG were eventually compared to corresponding signals directly available in the database. Comparison occurred in terms of signal similarity (evaluated by the correlation coefficient ρ, and the mean signal error MSE) and clinical features (including FHR baseline and variability; number, amplitude and duration of tachycardia, bradycardia, acceleration and deceleration episodes; number of early, variable, late and prolonged decelerations; and UC number, amplitude, duration and period). The value of ρ between eCTG and reference signals was 0.85 (P digital FHR and UC signals from digital CTG images. Copyright © 2018 Elsevier B.V. All rights reserved.

The hand: MR imaging with a 4.7-T magnet

International Nuclear Information System (INIS)

Wang, P.C.; Archer, A.; Rajan, S.; Carvlin, M.J.; Mun, S.K.; Nelson, M.C.

1987-01-01

MR images of normal and pathologic human hands were obtained using a 4.7-T magnet Varian system. Standard spin-echo techniques and inversion-recovery sequences were used to produce both T1- and T2-weighted images. The higher gradient (2 gauss/cm) of the 4.7-T system allows submillimeter resolution. A specially designed surface coil is used to improve the signal-to-noise ratio. The coil is elliptical and measures 3 inches by 4.5 inches. Axial, coronal, and sagittal images were obtained, revealing fine, detailed structures of the human hand. The joint capsule, ligaments and tendons, and vascular structures were clearly visible. The authors will show images of the normal anatomy of the hand, as well as pathologic lesions of inflammatory and crystalline arthropathy. Techniques and special problems of imaging the human hand with a 4.7-T system are discussed

Noncontrast magnetic resonance angiography of the hand: improved arterial conspicuity by multidirectional flow-sensitive dephasing magnetization preparation in 3D balanced steady-state free precession imaging.

Science.gov (United States)

Fan, Zhaoyang; Hodnett, Philip A; Davarpanah, Amir H; Scanlon, Timothy G; Sheehan, John J; Varga, John; Carr, James C; Li, Debiao

2011-08-01

: To develop a flow-sensitive dephasing (FSD) preparative scheme to facilitate multidirectional flow-signal suppression in 3-dimensional balanced steady-state free precession imaging and to validate the feasibility of the refined sequence for noncontrast magnetic resonance angiography (NC-MRA) of the hand. : A new FSD preparative scheme was developed that combines 2 conventional FSD modules. Studies using a flow phantom (gadolinium-doped water 15 cm/s) and the hands of 11 healthy volunteers (6 males and 5 females) were performed to compare the proposed FSD scheme with its conventional counterpart with respect to the signal suppression of multidirectional flow. In 9 of the 11 healthy subjects and 2 patients with suspected vasculitis and documented Raynaud phenomenon, respectively, 3-dimensional balanced steady-state free precession imaging coupled with the new FSD scheme was compared with spatial-resolution-matched (0.94 × 0.94 × 0.94 mm) contrast-enhanced magnetic resonance angiography (0.15 mmol/kg gadopentetate dimeglumine) in terms of overall image quality, venous contamination, motion degradation, and arterial conspicuity. : The proposed FSD scheme was able to suppress 2-dimensional flow signal in the flow phantom and hands and yielded significantly higher arterial conspicuity scores than the conventional scheme did on NC-MRA at the regions of common digitals and proper digitals. Compared with contrast-enhanced magnetic resonance angiography, the refined NC-MRA technique yielded comparable overall image quality and motion degradation, significantly less venous contamination, and significantly higher arterial conspicuity score at digital arteries. : The FSD-based NC-MRA technique is improved in the depiction of multidirectional flow by applying a 2-module FSD preparation, which enhances its potential to serve as an alternative magnetic resonance angiography technique for the assessment of hand vascular abnormalities.

Digital image display system for emergency room

International Nuclear Information System (INIS)

Murry, R.C.; Lane, T.J.; Miax, L.S.

1989-01-01

This paper reports on a digital image display system for the emergency room (ER) in a major trauma hospital. Its objective is to reduce radiographic image delivery time to a busy ER while simultaneously providing a multimodality capability. Image storage, retrieval, and display will also be facilitated with this system. The system's backbone is a token-ring network of RISC and personal computers. The display terminals are higher- function RISC computers with 1,024 2 color or gray-scale monitors. The PCs serve as administrative terminals. Nuclear medicine, CT, MR, and digitized film images are transferred to the image display system

Digital subtraction imaging in cardiac investigations

International Nuclear Information System (INIS)

Partridge, J.B.; Dickinson, D.F.

1984-01-01

The role of digital subtraction imaging (DSI) in the investigation of heart disease in patients of all ages, including neonates, was evaluated by the addition of a continuous fluoroscopy system to an existing, single-plane catheterisation laboratory. In some situations, DSI provided diagnostic images where conventional radiography could not and, in general, provided images of comparable quality to cineangiography. The total dose of contrast medium was usually less than that which would have been required for biplane cineangiography and the dose of radiation was always less. Digital subtraction imaging can make a significant contribution to the investigation of congenital heart disease and has some useful features in the study of acquired heart disease. (author)

Hand and digital ischemia due to arteriosclerosis and thromboembolization in young adults: pathologic features with clinical correlations.

Science.gov (United States)

Guarda, L A; Borrero, J L

1990-11-01

Twenty young adult patients with hand and digital ischemia were found to have obstructive arterial disease. All patients were surgically explored, and the occluded vessels were resected and by-passed. Eighteen patients had obstruction at the level of the distal ulnar artery and palmar arch, and 12 had obstruction of the common digital and digital proper arteries. Occlusive arteriosclerotic lesions were found in all patients; these lesions were characterized by prominent fibromuscular intimal plaques with superimposed thrombosis. Six patients had also thromboembolism to distal digital vessels. Vasculitis, calcifications, cholesterol deposits, and atheromatous emboli were not observed. Five patients had transmural neovascularization of the lesions in a similar manner to that described in coronary artery lesions. Obstructive lesions due to fibromuscular intimal proliferation with associated thrombosis and/or distal thromboembolization affecting arteries of hands and digits appear to be an important lesion that can affect young patients.

Analysis of Information Remaining on Hand Held Devices Offered for Sale on the Second Hand Market

Directory of Open Access Journals (Sweden)

Andy Jones

2008-06-01

resellers.The study was carried out by the security research team at the BT IT Futures Centre in conjunction with Edith Cowan University in Australia and the University of Glamorgan in the UK. The basis of the research was to acquire a number of second hand held devices from a diverse range of sources and then determine whether they still contained information relating to a previous owner or whether the information had been effectively removed. The devices that were obtained for the research were supplied blind to the researchers through a third party. The ‘blind’ supply of the devices meant that the people undertaking the research were provided with no information about the device and that the source of the devices and any external markings were hidden from them. This process was put in place to ensure that any findings of the research were based solely on the information that could be recovered from the digital storage media that was contained within the device.The underlying methodology that was used in the research was based on the forensic imaging of the devices. A forensic image of a device is a copy of the digital media that has been created in a scientifically sound manner to a standard that is acceptable to the courts. This procedure was implemented to ensure that the evidential integrity of the devices was maintained, with the devices also then being stored in a secure manner.  All subsequent research was then conducted on the image of the device. This was considered to be a sensible precaution against the possibility that information discovered on a device might indicate criminal activity and require the involvement of law enforcement.  Following the forensic imaging of the devices, the images that were created were then analyzed to determine whether any information remained and whether it could be easily recovered using commonly available tools and techniques that anyone who had purchased the device could acquire.

Eliminating "Hotspots" in Digital Image Processing

Science.gov (United States)

Salomon, P. M.

1984-01-01

Signals from defective picture elements rejected. Image processing program for use with charge-coupled device (CCD) or other mosaic imager augmented with algorithm that compensates for common type of electronic defect. Algorithm prevents false interpretation of "hotspots". Used for robotics, image enhancement, image analysis and digital television.

MO-AB-210-02: Ultrasound Imaging and Therapy-Hands On Workshop

International Nuclear Information System (INIS)

Sammet, S.

2015-01-01

The goal of this ultrasound hands-on workshop is to demonstrate advancements in high intensity focused ultrasound (HIFU) and to demonstrate quality control (QC) testing in diagnostic ultrasound. HIFU is a therapeutic modality that uses ultrasound waves as carriers of energy. HIFU is used to focus a beam of ultrasound energy into a small volume at specific target locations within the body. The focused beam causes localized high temperatures and produces a well-defined regions of necrosis. This completely non-invasive technology has great potential for tumor ablation and targeted drug delivery. At the workshop, attendees will see configurations, applications, and hands-on demonstrations with on-site instructors at separate stations. The involvement of medical physicists in diagnostic ultrasound imaging service is increasing due to QC and accreditation requirements. At the workshop, an array of ultrasound testing phantoms and ultrasound scanners will be provided for attendees to learn diagnostic ultrasound QC in a hands-on environment with live demonstrations of the techniques. Target audience: Medical physicists and other medical professionals in diagnostic imaging and radiation oncology with interest in high-intensity focused ultrasound and in diagnostic ultrasound QC. Learning Objectives: Learn ultrasound physics and safety for HIFU applications through live demonstrations Get an overview of the state-of-the art in HIFU technologies and equipment Gain familiarity with common elements of a quality control program for diagnostic ultrasound imaging Identify QC tools available for testing diagnostic ultrasound systems and learn how to use these tools List of supporting vendors for HIFU and diagnostic ultrasound QC hands-on workshop: Philips Healthcare Alpinion Medical Systems Verasonics, Inc Zonare Medical Systems, Inc Computerized Imaging Reference Systems (CIRS), Inc. GAMMEX, Inc., Cablon Medical BV Steffen Sammet: NIH/NCI grant 5R25CA132822, NIH/NINDS grant 5R25NS

MO-AB-210-01: Ultrasound Imaging and Therapy-Hands On Workshop

International Nuclear Information System (INIS)

Lu, Z.

2015-01-01

The goal of this ultrasound hands-on workshop is to demonstrate advancements in high intensity focused ultrasound (HIFU) and to demonstrate quality control (QC) testing in diagnostic ultrasound. HIFU is a therapeutic modality that uses ultrasound waves as carriers of energy. HIFU is used to focus a beam of ultrasound energy into a small volume at specific target locations within the body. The focused beam causes localized high temperatures and produces a well-defined regions of necrosis. This completely non-invasive technology has great potential for tumor ablation and targeted drug delivery. At the workshop, attendees will see configurations, applications, and hands-on demonstrations with on-site instructors at separate stations. The involvement of medical physicists in diagnostic ultrasound imaging service is increasing due to QC and accreditation requirements. At the workshop, an array of ultrasound testing phantoms and ultrasound scanners will be provided for attendees to learn diagnostic ultrasound QC in a hands-on environment with live demonstrations of the techniques. Target audience: Medical physicists and other medical professionals in diagnostic imaging and radiation oncology with interest in high-intensity focused ultrasound and in diagnostic ultrasound QC. Learning Objectives: Learn ultrasound physics and safety for HIFU applications through live demonstrations Get an overview of the state-of-the art in HIFU technologies and equipment Gain familiarity with common elements of a quality control program for diagnostic ultrasound imaging Identify QC tools available for testing diagnostic ultrasound systems and learn how to use these tools List of supporting vendors for HIFU and diagnostic ultrasound QC hands-on workshop: Philips Healthcare Alpinion Medical Systems Verasonics, Inc Zonare Medical Systems, Inc Computerized Imaging Reference Systems (CIRS), Inc. GAMMEX, Inc., Cablon Medical BV Steffen Sammet: NIH/NCI grant 5R25CA132822, NIH/NINDS grant 5R25NS

MO-AB-210-02: Ultrasound Imaging and Therapy-Hands On Workshop

Energy Technology Data Exchange (ETDEWEB)

Sammet, S. [University of Chicago Medical Center (United States)

2015-06-15

The goal of this ultrasound hands-on workshop is to demonstrate advancements in high intensity focused ultrasound (HIFU) and to demonstrate quality control (QC) testing in diagnostic ultrasound. HIFU is a therapeutic modality that uses ultrasound waves as carriers of energy. HIFU is used to focus a beam of ultrasound energy into a small volume at specific target locations within the body. The focused beam causes localized high temperatures and produces a well-defined regions of necrosis. This completely non-invasive technology has great potential for tumor ablation and targeted drug delivery. At the workshop, attendees will see configurations, applications, and hands-on demonstrations with on-site instructors at separate stations. The involvement of medical physicists in diagnostic ultrasound imaging service is increasing due to QC and accreditation requirements. At the workshop, an array of ultrasound testing phantoms and ultrasound scanners will be provided for attendees to learn diagnostic ultrasound QC in a hands-on environment with live demonstrations of the techniques. Target audience: Medical physicists and other medical professionals in diagnostic imaging and radiation oncology with interest in high-intensity focused ultrasound and in diagnostic ultrasound QC. Learning Objectives: Learn ultrasound physics and safety for HIFU applications through live demonstrations Get an overview of the state-of-the art in HIFU technologies and equipment Gain familiarity with common elements of a quality control program for diagnostic ultrasound imaging Identify QC tools available for testing diagnostic ultrasound systems and learn how to use these tools List of supporting vendors for HIFU and diagnostic ultrasound QC hands-on workshop: Philips Healthcare Alpinion Medical Systems Verasonics, Inc Zonare Medical Systems, Inc Computerized Imaging Reference Systems (CIRS), Inc. GAMMEX, Inc., Cablon Medical BV Steffen Sammet: NIH/NCI grant 5R25CA132822, NIH/NINDS grant 5R25NS

MO-AB-210-01: Ultrasound Imaging and Therapy-Hands On Workshop

Energy Technology Data Exchange (ETDEWEB)

Lu, Z. [University of Chicago (United States)

2015-06-15

The goal of this ultrasound hands-on workshop is to demonstrate advancements in high intensity focused ultrasound (HIFU) and to demonstrate quality control (QC) testing in diagnostic ultrasound. HIFU is a therapeutic modality that uses ultrasound waves as carriers of energy. HIFU is used to focus a beam of ultrasound energy into a small volume at specific target locations within the body. The focused beam causes localized high temperatures and produces a well-defined regions of necrosis. This completely non-invasive technology has great potential for tumor ablation and targeted drug delivery. At the workshop, attendees will see configurations, applications, and hands-on demonstrations with on-site instructors at separate stations. The involvement of medical physicists in diagnostic ultrasound imaging service is increasing due to QC and accreditation requirements. At the workshop, an array of ultrasound testing phantoms and ultrasound scanners will be provided for attendees to learn diagnostic ultrasound QC in a hands-on environment with live demonstrations of the techniques. Target audience: Medical physicists and other medical professionals in diagnostic imaging and radiation oncology with interest in high-intensity focused ultrasound and in diagnostic ultrasound QC. Learning Objectives: Learn ultrasound physics and safety for HIFU applications through live demonstrations Get an overview of the state-of-the art in HIFU technologies and equipment Gain familiarity with common elements of a quality control program for diagnostic ultrasound imaging Identify QC tools available for testing diagnostic ultrasound systems and learn how to use these tools List of supporting vendors for HIFU and diagnostic ultrasound QC hands-on workshop: Philips Healthcare Alpinion Medical Systems Verasonics, Inc Zonare Medical Systems, Inc Computerized Imaging Reference Systems (CIRS), Inc. GAMMEX, Inc., Cablon Medical BV Steffen Sammet: NIH/NCI grant 5R25CA132822, NIH/NINDS grant 5R25NS

Losing images in digital radiology: more than you think.

Science.gov (United States)

Oglevee, Catherine; Pianykh, Oleg

2015-06-01

It is a common belief that the shift to digital imaging some 20 years ago helped medical image exchange and got rid of any potential image loss that was happening with printed image films. Unfortunately, this is not the case: despite the most recent advances in digital imaging, most hospitals still keep losing their imaging data, with these losses going completely unnoticed. As a result, not only does image loss affect the faith in digital imaging but it also affects patient diagnosis and daily quality of clinical work. This paper identifies the origins of invisible image losses, provides methods and procedures to detect image loss, and demonstrates modes of action that can be taken to stop the problem from happening.

Quality assessment of the digitalization process of analog x-ray images

International Nuclear Information System (INIS)

Georgieva, D.

2014-01-01

Computer-assisted diagnosis enabled doctors for a second point-of-view on the test results. This improves the diseases' early detection and significantly reduces the chance of errors. These methods very nicely complemented the possibilities of digital medical imaging apparatus, but in analog images their applicability and results entirely depend on the quality of analog images digitalisation. Today many standards and remarks for good practices discuss the digital apparatus image quality but the digitalisation process of analog medical images is not a part of them. Medical imaging apparatus have become digital, but within an entirely digital medical environment is necessary for their ability to blend with the old analog medical imaging carriers. The life of patients doesn't start with the beginning of digital era and for the aim of tracking diseases it is necessary to use the new digital images as well as older analog ones. For the generation of 40-50 years a large archive of images is piled up, which should be accounted of in the diagnosis process. This article is the author's study of the digitalized image quality problem. It offers a new approach to the x-ray image digitalisation - getting the HDR-image by optical sensor. After the HDR-image generation method offers to be used a digital signal processing to improve the quality of the final 16 bit gray scale medical image. The new method for medical image enhancement is proposed - it improves the image contrast, it increases or preserves the dynamic range and it doesn't lead to the loss of small low contrast structures in the image. Key words: Quality of Digital X-Rays Images

A Methodology and Implementation for Annotating Digital Images for Context-appropriate Use in an Academic Health Care Environment

Science.gov (United States)

Goede, Patricia A.; Lauman, Jason R.; Cochella, Christopher; Katzman, Gregory L.; Morton, David A.; Albertine, Kurt H.

2004-01-01

Use of digital medical images has become common over the last several years, coincident with the release of inexpensive, mega-pixel quality digital cameras and the transition to digital radiology operation by hospitals. One problem that clinicians, medical educators, and basic scientists encounter when handling images is the difficulty of using business and graphic arts commercial-off-the-shelf (COTS) software in multicontext authoring and interactive teaching environments. The authors investigated and developed software-supported methodologies to help clinicians, medical educators, and basic scientists become more efficient and effective in their digital imaging environments. The software that the authors developed provides the ability to annotate images based on a multispecialty methodology for annotation and visual knowledge representation. This annotation methodology is designed by consensus, with contributions from the authors and physicians, medical educators, and basic scientists in the Departments of Radiology, Neurobiology and Anatomy, Dermatology, and Ophthalmology at the University of Utah. The annotation methodology functions as a foundation for creating, using, reusing, and extending dynamic annotations in a context-appropriate, interactive digital environment. The annotation methodology supports the authoring process as well as output and presentation mechanisms. The annotation methodology is the foundation for a Windows implementation that allows annotated elements to be represented as structured eXtensible Markup Language and stored separate from the image(s). PMID:14527971

Study of the inferior alveolar canal and mental foramen on digital panoramic images.

Science.gov (United States)

Pria, Carlos M; Masood, Farah; Beckerley, Joy M; Carson, Robert E

2011-07-01

To study the radiographic location of the mental foramen and appearance of the inferior alveolar canal and the relationship between image gray values and the clarity of inferior alveolar canal on the digital panoramic images and to evaluate if the histogram equalization of the digital image would improve the visualization of the inferior alveolar canal outline on the digital panoramic images in the mandible. Five hundred digital panoramic images were evaluated by two examiners using a specific inclusion criteria. Only the right side of the mandible was studied. Chi-square analyses were used for comparisons of distributions. Mean and median pixel values were analyzed separately with a one-way analysis of variance. Also, percentages were calculated to report the usefulness of the histogram equalization for visualization of canal. RESULTS show variation in location of mental foramen. Most frequent location of the mental foramen was reported as first and second premolar region. Chi-square analysis showed that the frequency of occurrence of the mental foramen was equally probable for any of the three locations. The study did not find significant usefulness of the gray values obtained from the histogram equalization in predicting the clarity of inferior alveolar canal outlines. Knowing the normal relationship and the anatomical variation of the maxillofacial structures for each patient is important for surgical implant treatment planning to avoid future complications. It is also important to be familiar with the advantages and limitations of diagnostic aids available before making treatment planning decisions based on such findings. Digital imaging, Panoramic, Inferior alveolar canal, Mental foramen. How to cite this article: Pria CM, Masood F, Beckerley JM, Carson RE. Study of the Inferior Alveolar Canal and Mental Foramen on Digital Panoramic Images. J Contemp Dent Pract 2011;12(4):265-271. Source of support: Nil Conflict of interest: None declared.

Ethical Implications of Digital Imaging in Photojournalism.

Science.gov (United States)

Terry, Danal; Lasorsa, Dominic L.

Arguing that the news media are about to adopt digital imaging systems that will have far-reaching implications for the practice of journalism, this paper discusses how the news media is expected to adopt the new technology and explains why the marriage of journalism and digital imaging will create ethical issues with respect to photo manipulation…

A kind of video image digitizing circuit based on computer parallel port

International Nuclear Information System (INIS)

Wang Yi; Tang Le; Cheng Jianping; Li Yuanjing; Zhang Binquan

2003-01-01

A kind of video images digitizing circuit based on parallel port was developed to digitize the flash x ray images in our Multi-Channel Digital Flash X ray Imaging System. The circuit can digitize the video images and store in static memory. The digital images can be transferred to computer through parallel port and can be displayed, processed and stored. (authors)

Automated quadrilateral mesh generation for digital image structures

Institute of Scientific and Technical Information of China (English)

无

2011-01-01

With the development of advanced imaging technology, digital images are widely used. This paper proposes an automatic quadrilateral mesh generation algorithm for multi-colour imaged structures. It takes an original arbitrary digital image as an input for automatic quadrilateral mesh generation, this includes removing the noise, extracting and smoothing the boundary geometries between different colours, and automatic all-quad mesh generation with the above boundaries as constraints. An application example is...

Digital image processing and analysis human and computer vision applications with CVIPtools

CERN Document Server

Umbaugh, Scott E

2010-01-01

Section I Introduction to Digital Image Processing and AnalysisDigital Image Processing and AnalysisOverviewImage Analysis and Computer VisionImage Processing and Human VisionKey PointsExercisesReferencesFurther ReadingComputer Imaging SystemsImaging Systems OverviewImage Formation and SensingCVIPtools SoftwareImage RepresentationKey PointsExercisesSupplementary ExercisesReferencesFurther ReadingSection II Digital Image Analysis and Computer VisionIntroduction to Digital Image AnalysisIntroductionPreprocessingBinary Image AnalysisKey PointsExercisesSupplementary ExercisesReferencesFurther Read

Digital Data Processing of Images

African Journals Online (AJOL)

Digital data processing was investigated to perform image processing. Image smoothing and restoration were explored and promising results obtained. The use of the computer, not only as a data management device, but as an important tool to render quantitative information, was illustrated by lung function determination.

Self-adaptive isogeometric global digital image correlation and digital height correlation

NARCIS (Netherlands)

Hoefnagels, J. P M; Kleinendorst, S. M.; Ruybalid, A. P.; Verhoosel, C. V.; Geers, M. G D; Yoshida, S.; Lamberti, L.; Sciammarella, C.

2017-01-01

This work explores the full potential of isogeometric shape functions for global digital image correlation. To this end, a novel DIC and DHC (digital height correlation) methodology have been developed based on adaptive refinement of isogeometric shape functions. Non-Uniform Rational B-Spline

Digitalization and networking of analog simulators and portal images.

Science.gov (United States)

Pesznyák, Csilla; Zaránd, Pál; Mayer, Arpád

2007-03-01

Many departments have analog simulators and irradiation facilities (especially cobalt units) without electronic portal imaging. Import of the images into the R&V (Record & Verify) system is required. Simulator images are grabbed while portal films scanned by using a laser scanner and both converted into DICOM RT (Digital Imaging and Communications in Medicine Radiotherapy) images. Image intensifier output of a simulator and portal films are converted to DICOM RT images and used in clinical practice. The simulator software was developed in cooperation at the authors' hospital. The digitalization of analog simulators is a valuable updating in clinical use replacing screen-film technique. Film scanning and digitalization permit the electronic archiving of films. Conversion into DICOM RT images is a precondition of importing to the R&V system.

Gen-2 Hand-Held Optical Imager towards Cancer Imaging: Reflectance and Transillumination Phantom Studies

Directory of Open Access Journals (Sweden)

Anuradha Godavarty

2012-02-01

Full Text Available Hand-held near-infrared (NIR optical imagers are developed by various researchers towards non-invasive clinical breast imaging. Unlike these existing imagers that can perform only reflectance imaging, a generation-2 (Gen-2 hand-held optical imager has been recently developed to perform both reflectance and transillumination imaging. The unique forked design of the hand-held probe head(s allows for reflectance imaging (as in ultrasound and transillumination or compressed imaging (as in X-ray mammography. Phantom studies were performed to demonstrate two-dimensional (2D target detection via reflectance and transillumination imaging at various target depths (1–5 cm deep and using simultaneous multiple point illumination approach. It was observed that 0.45 cc targets were detected up to 5 cm deep during transillumination, but limited to 2.5 cm deep during reflectance imaging. Additionally, implementing appropriate data post-processing techniques along with a polynomial fitting approach, to plot 2D surface contours of the detected signal, yields distinct target detectability and localization. The ability of the gen-2 imager to perform both reflectance and transillumination imaging allows its direct comparison to ultrasound and X-ray mammography results, respectively, in future clinical breast imaging studies.

Improving image quality of parallel phase-shifting digital holography

International Nuclear Information System (INIS)

Awatsuji, Yasuhiro; Tahara, Tatsuki; Kaneko, Atsushi; Koyama, Takamasa; Nishio, Kenzo; Ura, Shogo; Kubota, Toshihiro; Matoba, Osamu

2008-01-01

The authors propose parallel two-step phase-shifting digital holography to improve the image quality of parallel phase-shifting digital holography. The proposed technique can increase the effective number of pixels of hologram twice in comparison to the conventional parallel four-step technique. The increase of the number of pixels makes it possible to improve the image quality of the reconstructed image of the parallel phase-shifting digital holography. Numerical simulation and preliminary experiment of the proposed technique were conducted and the effectiveness of the technique was confirmed. The proposed technique is more practical than the conventional parallel phase-shifting digital holography, because the composition of the digital holographic system based on the proposed technique is simpler.

Introduction to digital image processing

CERN Document Server

Pratt, William K

2013-01-01

CONTINUOUS IMAGE CHARACTERIZATION Continuous Image Mathematical Characterization Image RepresentationTwo-Dimensional SystemsTwo-Dimensional Fourier TransformImage Stochastic CharacterizationPsychophysical Vision Properties Light PerceptionEye PhysiologyVisual PhenomenaMonochrome Vision ModelColor Vision ModelPhotometry and ColorimetryPhotometryColor MatchingColorimetry ConceptsColor SpacesDIGITAL IMAGE CHARACTERIZATION Image Sampling and Reconstruction Image Sampling and Reconstruction ConceptsMonochrome Image Sampling SystemsMonochrome Image Reconstruction SystemsColor Image Sampling SystemsImage QuantizationScalar QuantizationProcessing Quantized VariablesMonochrome and Color Image QuantizationDISCRETE TWO-DIMENSIONAL LINEAR PROCESSING Discrete Image Mathematical Characterization Vector-Space Image RepresentationGeneralized Two-Dimensional Linear OperatorImage Statistical CharacterizationImage Probability Density ModelsLinear Operator Statistical RepresentationSuperposition and ConvolutionFinite-Area Superp...

An image adaptive, wavelet-based watermarking of digital images

Science.gov (United States)

Agreste, Santa; Andaloro, Guido; Prestipino, Daniela; Puccio, Luigia

2007-12-01

In digital management, multimedia content and data can easily be used in an illegal way--being copied, modified and distributed again. Copyright protection, intellectual and material rights protection for authors, owners, buyers, distributors and the authenticity of content are crucial factors in solving an urgent and real problem. In such scenario digital watermark techniques are emerging as a valid solution. In this paper, we describe an algorithm--called WM2.0--for an invisible watermark: private, strong, wavelet-based and developed for digital images protection and authenticity. Using discrete wavelet transform (DWT) is motivated by good time-frequency features and well-matching with human visual system directives. These two combined elements are important in building an invisible and robust watermark. WM2.0 works on a dual scheme: watermark embedding and watermark detection. The watermark is embedded into high frequency DWT components of a specific sub-image and it is calculated in correlation with the image features and statistic properties. Watermark detection applies a re-synchronization between the original and watermarked image. The correlation between the watermarked DWT coefficients and the watermark signal is calculated according to the Neyman-Pearson statistic criterion. Experimentation on a large set of different images has shown to be resistant against geometric, filtering and StirMark attacks with a low rate of false alarm.

Endless everyday images: links and excesses in digital image

Directory of Open Access Journals (Sweden)

Ana Cláudia do Amaral Leão

2013-08-01

Full Text Available The research analyzed the relationships and communication links between overproduced images on digital media and their carriers. I start from the hypothesis that the way we look, record, save and access images have been deeply modified with the advent of digital cameras and ‘phone cameras’ – encouraging an addictive behavior for pictures. The method was based on interviews with ten informers – the images’ carriers, who let us conclude that we are overproducing pictures as information. In this context arise the producers of endless everyday pictures, here named ‘photomaniacs’, who give birth two kinds of images: the circulatory infoimages and the everyday infoimages. Overproduced digital images transform devices in our magnifiers of memory and oblivion, undoing the way we compile, save or file – and operating in cumulative, disordered, small and private stock of images. Thus, we try to saturate our most superficial memory, that generates schizophrenic pictures when operates on excess. However, even if the way is only technological, we must remember that the body is the living organism suitable to pictures, the place where we hold deep bonding relations. Over this body surface, images survive impregnated of meanings, links, belonging and healing. The research was based on the theories of communication links of Boris Cyrulnik, Jose Ângelo Gaiarsa and Ashley Montagu, besides the works on images and schizophrenia of Nise da Silveira and Leo Navratil. The research also activated the central European stream of Cultural Semiotics, specially the theories of images proposed by Aby Warburg, Walter Benjamin, Dietmar Kamper, Norval Baitello Junior, Hans Belting and Vilém Flusser.

Estimation of breast percent density in raw and processed full field digital mammography images via adaptive fuzzy c-means clustering and support vector machine segmentation

Energy Technology Data Exchange (ETDEWEB)

Keller, Brad M.; Nathan, Diane L.; Wang Yan; Zheng Yuanjie; Gee, James C.; Conant, Emily F.; Kontos, Despina [Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania 19104 (United States); Applied Mathematics and Computational Science, University of Pennsylvania, Philadelphia, Pennsylvania 19104 (United States); Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania 19104 (United States)

2012-08-15

Purpose: The amount of fibroglandular tissue content in the breast as estimated mammographically, commonly referred to as breast percent density (PD%), is one of the most significant risk factors for developing breast cancer. Approaches to quantify breast density commonly focus on either semiautomated methods or visual assessment, both of which are highly subjective. Furthermore, most studies published to date investigating computer-aided assessment of breast PD% have been performed using digitized screen-film mammograms, while digital mammography is increasingly replacing screen-film mammography in breast cancer screening protocols. Digital mammography imaging generates two types of images for analysis, raw (i.e., 'FOR PROCESSING') and vendor postprocessed (i.e., 'FOR PRESENTATION'), of which postprocessed images are commonly used in clinical practice. Development of an algorithm which effectively estimates breast PD% in both raw and postprocessed digital mammography images would be beneficial in terms of direct clinical application and retrospective analysis. Methods: This work proposes a new algorithm for fully automated quantification of breast PD% based on adaptive multiclass fuzzy c-means (FCM) clustering and support vector machine (SVM) classification, optimized for the imaging characteristics of both raw and processed digital mammography images as well as for individual patient and image characteristics. Our algorithm first delineates the breast region within the mammogram via an automated thresholding scheme to identify background air followed by a straight line Hough transform to extract the pectoral muscle region. The algorithm then applies adaptive FCM clustering based on an optimal number of clusters derived from image properties of the specific mammogram to subdivide the breast into regions of similar gray-level intensity. Finally, a SVM classifier is trained to identify which clusters within the breast tissue are likely

Dynamic imaging through turbid media based on digital holography.

Science.gov (United States)

Li, Shiping; Zhong, Jingang

2014-03-01

Imaging through turbid media using visible or IR light instead of harmful x ray is still a challenging problem, especially in dynamic imaging. A method of dynamic imaging through turbid media using digital holography is presented. In order to match the coherence length between the dynamic object wave and the reference wave, a cw laser is used. To solve the problem of difficult focusing in imaging through turbid media, an autofocus technology is applied. To further enhance the image contrast, a spatial filtering technique is used. A description of digital holography and experiments of imaging the objects hidden in turbid media are presented. The experimental result shows that dynamic images of the objects can be achieved by the use of digital holography.

Digital memory for TV image information

International Nuclear Information System (INIS)

Paretti, C.

1975-01-01

A system employing closed circuit TV camera and MOS memory is presented to take image information and store it. The apparatus is made in two sections: analog filters and digital memory. Filters have been used to select low amplitude signals from high frequency and low frequency noise components. The memory is arranged to make nondestroying overlap of digit array: this facility is useful for microscope image prejection to overcome depth of field limits, as in automatic nuclear emulsion scanners for personnel radiation monitoring. (author)

System for objective assessment of image differences in digital cinema

Science.gov (United States)

Fliegel, Karel; Krasula, Lukáš; Páta, Petr; Myslík, Jiří; Pecák, Josef; Jícha, Marek

2014-09-01

There is high demand for quick digitization and subsequent image restoration of archived film records. Digitization is very urgent in many cases because various invaluable pieces of cultural heritage are stored on aging media. Only selected records can be reconstructed perfectly using painstaking manual or semi-automatic procedures. This paper aims to answer the question what are the quality requirements on the restoration process in order to obtain acceptably close visual perception of the digitally restored film in comparison to the original analog film copy. This knowledge is very important to preserve the original artistic intention of the movie producers. Subjective experiment with artificially distorted images has been conducted in order to answer the question what is the visual impact of common image distortions in digital cinema. Typical color and contrast distortions were introduced and test images were presented to viewers using digital projector. Based on the outcome of this subjective evaluation a system for objective assessment of image distortions has been developed and its performance tested. The system utilizes calibrated digital single-lens reflex camera and subsequent analysis of suitable features of images captured from the projection screen. The evaluation of captured image data has been optimized in order to obtain predicted differences between the reference and distorted images while achieving high correlation with the results of subjective assessment. The system can be used to objectively determine the difference between analog film and digital cinema images on the projection screen.

Problems with Permatrace: a note on digital image publication

Directory of Open Access Journals (Sweden)

Guy Hopkinson

2004-01-01

Full Text Available The methodology presented here developed out of work required to convert the hard-copy illustrations submitted to Internet Archaeology for publication of the 1975 excavations at Cricklade. The publication (and digital image preparatory work was funded by English Heritage and was, in part, an experiment designed to explore some of the possibilities presented by digital image publication. Various challenges in how to transform the drawings on permatrace to a digital format were encountered. While a full exploration of the potential of all areas of digital image preparation and publication was not possible, some interesting technical options were evaluated. This short article explains the processes applied in creating the images that were finally incorporated within the publication. It also examines some other avenues regarding the presentation of archaeological drawings that could be explored in both future Internet Archaeology content and other digital publications.

The FBI compression standard for digitized fingerprint images

Energy Technology Data Exchange (ETDEWEB)

Brislawn, C.M.; Bradley, J.N. [Los Alamos National Lab., NM (United States); Onyshczak, R.J. [National Inst. of Standards and Technology, Gaithersburg, MD (United States); Hopper, T. [Federal Bureau of Investigation, Washington, DC (United States)

1996-10-01

The FBI has formulated national standards for digitization and compression of gray-scale fingerprint images. The compression algorithm for the digitized images is based on adaptive uniform scalar quantization of a discrete wavelet transform subband decomposition, a technique referred to as the wavelet/scalar quantization method. The algorithm produces archival-quality images at compression ratios of around 15 to 1 and will allow the current database of paper fingerprint cards to be replaced by digital imagery. A compliance testing program is also being implemented to ensure high standards of image quality and interchangeability of data between different implementations. We will review the current status of the FBI standard, including the compliance testing process and the details of the first-generation encoder.

The role of camera-bundled image management software in the consumer digital imaging value chain

Science.gov (United States)

Mueller, Milton; Mundkur, Anuradha; Balasubramanian, Ashok; Chirania, Virat

2005-02-01

This research was undertaken by the Convergence Center at the Syracuse University School of Information Studies (www.digital-convergence.info). Project ICONICA, the name for the research, focuses on the strategic implications of digital Images and the CONvergence of Image management and image CApture. Consumer imaging - the activity that we once called "photography" - is now recognized as in the throes of a digital transformation. At the end of 2003, market researchers estimated that about 30% of the households in the U.S. and 40% of the households in Japan owned digital cameras. In 2004, of the 86 million new cameras sold (excluding one-time use cameras), a majority (56%) were estimated to be digital cameras. Sales of photographic film, while still profitable, are declining precipitously.

Digital networks for the image management

International Nuclear Information System (INIS)

Gomez del Campo L, A.

1999-01-01

The digital networks designed specifically for the X-ray departments in the hospitals already were found in open development at beginning the 80's decade. Actually the digital network will be present include the image generation without the necessity to use film in direct form and in its case to print it through a laser ray printers network, an electronic image file, the possibility to integrate the hospitable information system to the electronic expedient which will allow communicate radiograph electronic files and consult by satellite via the problem cases. (Author)

Quality assurance in digital dental imaging: a systematic review.

Science.gov (United States)

Metsälä, Eija; Henner, Anja; Ekholm, Marja

2014-07-01

Doses induced by individual dental examinations are low. However, dental radiography accounts for nearly one third of the total number of radiological examinations in the European Union. Therefore, special attention is needed with regard to radiation protection. In order to lower patient doses, the staff performing dental examinations must have competence in imaging as well as in radiation protection issues. This paper presents a systematic review about the core competencies needed by the healthcare staff in performing digital dental radiological imaging quality assurance. The following databases were searched: Pubmed, Cinahl, Pro Quest and IEEXplore digital library. Also volumes of some dental imaging journals and doctoral theses of the Finnish universities educating dentists were searched. The search was performed using both MeSH terms and keywords using the option 'search all text'. The original keywords were: dental imaging, digital, x-ray, panoramic, quality, assurance, competence, competency, skills, knowledge, radiographer, radiologist technician, dentist, oral hygienist, radiation protection and their Finnish synonyms. Core competencies needed by the healthcare staff performing digital dental radiological imaging quality assurance described in the selected studies were: management of dental imaging equipment, competence in image quality and factors associated with it, dose optimization and quality assurance. In the future there will be higher doses in dental imaging due to increasing use of CBCT and digital imaging. The staff performing dental imaging must have competence in dental imaging quality assurance issues found in this review. They also have to practice ethical radiation safety culture in clinical practice.

Digitalization and networking of analog simulators and portal images

Energy Technology Data Exchange (ETDEWEB)

Pesznyak, C.; Zarand, P.; Mayer, A. [Uzsoki Hospital, Budapest (Hungary). Inst. of Oncoradiology

2007-03-15

Background: Many departments have analog simulators and irradiation facilities (especially cobalt units) without electronic portal imaging. Import of the images into the R and V (Record and Verify) system is required. Material and Methods: Simulator images are grabbed while portal films scanned by using a laser scanner and both converted into DICOM RT (Digital Imaging and Communications in Medicine Radiotherapy) images. Results: Image intensifier output of a simulator and portal films are converted to DICOM RT images and used in clinical practice. The simulator software was developed in cooperation at the authors' hospital. Conclusion: The digitalization of analog simulators is a valuable updating in clinical use replacing screen-film technique. Film scanning and digitalization permit the electronic archiving of films. Conversion into DICOM RT images is a precondition of importing to the R and V system. (orig.)

Grid-supported Medical Digital Library.

Science.gov (United States)

Kosiedowski, Michal; Mazurek, Cezary; Stroinski, Maciej; Weglarz, Jan

2007-01-01

Secure, flexible and efficient storing and accessing digital medical data is one of the key elements for delivering successful telemedical systems. To this end grid technologies designed and developed over the recent years and grid infrastructures deployed with their use seem to provide an excellent opportunity for the creation of a powerful environment capable of delivering tools and services for medical data storage, access and processing. In this paper we present the early results of our work towards establishing a Medical Digital Library supported by grid technologies and discuss future directions of its development. These works are part of the "Telemedycyna Wielkopolska" project aiming to develop a telemedical system for the support of the regional healthcare.

Three-dimensional digital breast histopathology imaging

Science.gov (United States)

Clarke, G. M.; Peressotti, C.; Mawdsley, G. E.; Eidt, S.; Ge, M.; Morgan, T.; Zubovits, J. T.; Yaffe, M. J.

2005-04-01

We have developed a digital histology imaging system that has the potential to improve the accuracy of surgical margin assessment in the treatment of breast cancer by providing finer sampling and 3D visualization. The system is capable of producing a 3D representation of histopathology from an entire lumpectomy specimen. We acquire digital photomicrographs of a stack of large (120 x 170 mm) histology slides cut serially through the entire specimen. The images are then registered and displayed in 2D and 3D. This approach dramatically improves sampling and can improve visualization of tissue structures compared to current, small-format histology. The system consists of a brightfield microscope, adapted with a freeze-frame digital video camera and a large, motorized translation stage. The image of each slide is acquired as a mosaic of adjacent tiles, each tile representing one field-of-view of the microscope, and the mosaic is assembled into a seamless composite image. The assembly is done by a program developed to build image sets at six different levels within a multiresolution pyramid. A database-linked viewing program has been created to efficiently register and display the animated stack of images, which occupies about 80 GB of disk space per lumpectomy at full resolution, on a high-resolution (3840 x 2400 pixels) colour monitor. The scanning or tiling approach to digitization is inherently susceptible to two artefacts which disrupt the composite image, and which impose more stringent requirements on system performance. Although non-uniform illumination across any one isolated tile may not be discernible, the eye readily detects this non-uniformity when the entire assembly of tiles is viewed. The pattern is caused by deficiencies in optical alignment, spectrum of the light source, or camera corrections. The imaging task requires that features as small as 3.2 &mum in extent be seamlessly preserved. However, inadequate accuracy in positioning of the translation

Effects of scanning resolution and digital image magnification on photostimulable phosphor imaging system

International Nuclear Information System (INIS)

Sakurai, Takashi; Inagaki, Masafumi; Asai, Hideomi; Koyama, Atsushi; Kashima, Isamu

2000-01-01

The purpose of this study is to examine the effects of changes in scanning resolution and digital magnification on the image quality and diagnostic ability of the photostimulable phosphor imaging system. Using a photostimulable phosphor imaging system, images of a human adult dried mandible phantom embedded in a 25 mm-thick epoxy resin block were made. The latent images on the photostimulable phosphor imaging plate were scanned using four different pixel sizes as follows: 25 μm x 25 μm, 50 μm x 50 μm, 100 μm x 100 μm and 200 μm x 200 μm. A primary image was produced for each pixel size. These images were also digitally magnified at powers of 2, 4 and 8 times. The gradient range, brightness and contrast of each image were adjusted to optimum levels on a cathode ray tube display, and hard copies were produced with a writing pixel size of 60 μm x 60 μm. The granularity, sharpness and anatomical diagnostic ability of the images were assessed subjectively by eight dentists. Increasing the scanning resolution tended to generally improve image quality and diagnostic ability. Visual image quality was maintained up to a pixel size of 50 μm, and diagnostic ability was maintained up to a pixel size of 100 μm. Digital image magnification degraded image quality, and more than 2-times magnification degraded diagnostic ability. Under the present experimental conditions, increasing the scanning resolution did not always lead to an improvement in image quality or diagnostic ability, and digital image magnification degraded image quality and diagnostic ability. (author)

Bilateral ce-MR angiography of the hands at 3.0 T and 1.5 T: intraindividual comparison of quantitative and qualitative image parameters in healthy volunteers

International Nuclear Information System (INIS)

Winterer, Jan T.; Markl, Michael; Frydrychowicz, Alexander; Bley, Thorsten A.; Langer, Mathias; Moske-Eick, Olaf

2008-01-01

The purpose of this study was to determine the benefit of bilateral contrast-enhanced MR angiography (ce-MRA) of the hands at 3.0 Tesla (T) compared with an established 1.5-T technique in healthy volunteers. Intraindividual bilateral ce-MRA of the hands was performed at 1.5 T and 3.0 T in 14 healthy volunteers using a timed ultra-fast GRE sequence featuring parallel acquisition. The evaluation comprised measurement of the vessel signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR), rating of the image quality and the assessment of artefacts and venous contamination. At 3.0 T, SNR improved up to 95% and CNR up to 129%. The image quality of the larger inflow arteries, the palm arches and common digital arteries was good or sufficient at either magnetic field strengths. However, 3.0-T MRA was clearly superior in the depiction of the digital arteries. Ce-MRA of the hand clearly profits from the use of 3.0 T. Compared with 1.5 T, a substantial increase of CNR is found resulting in a significantly better delineation of the small digital arteries. Saturation affects more the SNR of the perivascular tissue than the contrast-enhanced blood, and thus leads to a marked increase of CNR at 3.0. (orig.)

Image quality of digital mammography images produced using wet and dry laser imaging systems

International Nuclear Information System (INIS)

Al Khalifah, K.; Brindhaban, A.; AlArfaj, R.; Jassim, O.

2006-01-01

Introduction: A study was carried out to compare the quality of digital mammographic images printed or processed by a wet laser imaging system and a dedicated mammographic dry laser imaging system. Material and methods: Digital images of a tissue equivalent breast phantom were obtained using a GE Senographe 2000D digital mammography system and different target/filter combinations of the X-ray tube. These images were printed on films using the Fuji FL-IM D wet laser imaging system and the Kodak DryView 8600 dry laser imaging system. The quality of images was assessed in terms of detectability of microcalcifications and simulated tumour masses by five radiologists. In addition, the contrast index and speed index of the two systems were measured using the step wedge in the phantom. The unpaired, unequal variance t-test was used to test any statistically significant differences. Results: There were no significant (p < 0.05) differences between the images printed using the two systems in terms of microcalcification and tumour mass detectability. The wet system resulted in slightly higher contrast index while the dry system showed significantly higher speed index. Conclusion: Both wet and dry laser imaging systems can produce mammography images of good quality on which 0.2 mm microcalcifications and 2 mm tumour masses can be detected. Dry systems are preferable due to the absence of wet chemical processing and solid or liquid chemical waste. The wet laser imaging systems, however, still represent a useful alternative to dry laser imaging systems for mammography studies

Practical digital mammography

Energy Technology Data Exchange (ETDEWEB)

Hashimoto, Beverly E. [Washington Univ., Seattle, WA (United States)]|[Virginia Mason Medical Center, VA (United States)

2008-07-01

This book is meant for the radiologist who is facing the challenge of organizing a digital mammographic imaging center. This text is meant to be a practical book that provides information about digital mammographic physics and equipment which will allow one to intelligently compare technologies and systems. Some of the major challenges include: large expense; rapidly changing technology, and inconsistent connectivity; and finally, need for strong information technology support. The initial conversion cost to digital mammographic imaging is relatively expensive due to the cost of digital mammography hardware, software, and storage. Virtually all other imaging modalities are being converted to purely digital storage and transfer, and the digital trend in mammography is inevitable. Technical advantages of digital mammography are described. However, the improved flexibility in image display and transfer are some of its strongest features. In conclusion, although there are increasing imaging modalities that may be used to evaluate breast disease, mammography will continue to play a key role in detecting breast cancer. To be an effective imager, the radiologist should become familiar with digital mammography and understand its role within the increasing complex structure of breast imaging techniques.

Practical digital mammography

International Nuclear Information System (INIS)

Hashimoto, Beverly E.

2008-01-01

This book is meant for the radiologist who is facing the challenge of organizing a digital mammographic imaging center. This text is meant to be a practical book that provides information about digital mammographic physics and equipment which will allow one to intelligently compare technologies and systems. Some of the major challenges include: large expense; rapidly changing technology, and inconsistent connectivity; and finally, need for strong information technology support. The initial conversion cost to digital mammographic imaging is relatively expensive due to the cost of digital mammography hardware, software, and storage. Virtually all other imaging modalities are being converted to purely digital storage and transfer, and the digital trend in mammography is inevitable. Technical advantages of digital mammography are described. However, the improved flexibility in image display and transfer are some of its strongest features. In conclusion, although there are increasing imaging modalities that may be used to evaluate breast disease, mammography will continue to play a key role in detecting breast cancer. To be an effective imager, the radiologist should become familiar with digital mammography and understand its role within the increasing complex structure of breast imaging techniques

Automatic registration of fused lidar/digital imagery (texel images) for three-dimensional image creation

Science.gov (United States)

Budge, Scott E.; Badamikar, Neeraj S.; Xie, Xuan

2015-03-01

Several photogrammetry-based methods have been proposed that the derive three-dimensional (3-D) information from digital images from different perspectives, and lidar-based methods have been proposed that merge lidar point clouds and texture the merged point clouds with digital imagery. Image registration alone has difficulty with smooth regions with low contrast, whereas point cloud merging alone has difficulty with outliers and a lack of proper convergence in the merging process. This paper presents a method to create 3-D images that uses the unique properties of texel images (pixel-fused lidar and digital imagery) to improve the quality and robustness of fused 3-D images. The proposed method uses both image processing and point-cloud merging to combine texel images in an iterative technique. Since the digital image pixels and the lidar 3-D points are fused at the sensor level, more accurate 3-D images are generated because registration of image data automatically improves the merging of the point clouds, and vice versa. Examples illustrate the value of this method over other methods. The proposed method also includes modifications for the situation where an estimate of position and attitude of the sensor is known, when obtained from low-cost global positioning systems and inertial measurement units sensors.

The wavelet/scalar quantization compression standard for digital fingerprint images

Energy Technology Data Exchange (ETDEWEB)

Bradley, J.N.; Brislawn, C.M.

1994-04-01

A new digital image compression standard has been adopted by the US Federal Bureau of Investigation for use on digitized gray-scale fingerprint images. The algorithm is based on adaptive uniform scalar quantization of a discrete wavelet transform image decomposition and is referred to as the wavelet/scalar quantization standard. The standard produces archival quality images at compression ratios of around 20:1 and will allow the FBI to replace their current database of paper fingerprint cards with digital imagery.

The influence of software filtering in digital mammography image quality

Science.gov (United States)

Michail, C.; Spyropoulou, V.; Kalyvas, N.; Valais, I.; Dimitropoulos, N.; Fountos, G.; Kandarakis, I.; Panayiotakis, G.

2009-05-01

Breast cancer is one of the most frequently diagnosed cancers among women. Several techniques have been developed to help in the early detection of breast cancer such as conventional and digital x-ray mammography, positron and single-photon emission mammography, etc. A key advantage in digital mammography is that images can be manipulated as simple computer image files. Thus non-dedicated commercially available image manipulation software can be employed to process and store the images. The image processing tools of the Photoshop (CS 2) software usually incorporate digital filters which may be used to reduce image noise, enhance contrast and increase spatial resolution. However, improving an image quality parameter may result in degradation of another. The aim of this work was to investigate the influence of three sharpening filters, named hereafter sharpen, sharpen more and sharpen edges on image resolution and noise. Image resolution was assessed by means of the Modulation Transfer Function (MTF).In conclusion it was found that the correct use of commercial non-dedicated software on digital mammograms may improve some aspects of image quality.

The influence of software filtering in digital mammography image quality

International Nuclear Information System (INIS)

Michail, C; Spyropoulou, V; Valais, I; Panayiotakis, G; Kalyvas, N; Fountos, G; Kandarakis, I; Dimitropoulos, N

2009-01-01

Breast cancer is one of the most frequently diagnosed cancers among women. Several techniques have been developed to help in the early detection of breast cancer such as conventional and digital x-ray mammography, positron and single-photon emission mammography, etc. A key advantage in digital mammography is that images can be manipulated as simple computer image files. Thus non-dedicated commercially available image manipulation software can be employed to process and store the images. The image processing tools of the Photoshop (CS 2) software usually incorporate digital filters which may be used to reduce image noise, enhance contrast and increase spatial resolution. However, improving an image quality parameter may result in degradation of another. The aim of this work was to investigate the influence of three sharpening filters, named hereafter sharpen, sharpen more and sharpen edges on image resolution and noise. Image resolution was assessed by means of the Modulation Transfer Function (MTF).In conclusion it was found that the correct use of commercial non-dedicated software on digital mammograms may improve some aspects of image quality.

A feasibility study of hand kinematics for EVA analysis using magnetic resonance imaging

Science.gov (United States)

Dickenson, Rueben D.; Lorenz, Christine H.; Peterson, Steven W.; Strauss, Alvin M.; Main, John A.

1992-01-01

A new method of analyzing the kinematics of joint motion is developed. Magnetic Resonance Imaging (MRI) offers several distinct advantages. Past methods of studying anatomic joint motion have usually centered on four approaches. These methods are x-ray projection, goniometric linkage analysis, sonic digitization, and landmark measurement of photogrammetry. Of these four, only x-ray is applicable for in vivo studies. The remaining three methods utilize other types of projections of inter-joint measurements, which can cause various types of error. MRI offers accuracy in measurement due to its tomographic nature (as opposed to projection) without the problems associated with x-ray dosage. Once the data acquisition of MR images was complete, the images were processed using a 3D volume rendering workstation. The metacarpalphalangeal (MCP) joint of the left index finger was selected and reconstructed into a three-dimensional graphic display. From the reconstructed volumetric images, measurements of the angles of movement of the applicable bones were obtained and processed by analyzing the screw motion of the MCP joint. Landmark positions were chosen at distinctive locations of the joint at fixed image threshold intensity levels to ensure repeatability. The primarily two dimensional planar motion of this joint was then studied using a method of constructing coordinate systems using three (or more) points. A transformation matrix based on a world coordinate system described the location and orientation of a local target coordinate system. Future research involving volume rendering of MRI data focusing on the internal kinematics of the hand's individual ligaments, cartilage, tendons, etc. will follow. Its findings will show the applicability of MRI to joint kinematics for gaining further knowledge of the hand-glove (power assisted) design for extravehicular activity (EVA).

Moiré Effect: Index and the Digital Image

Directory of Open Access Journals (Sweden)

Stella Baraklianou

2014-10-01

Full Text Available The moiré effect and phenomena are natural occurring geometric formations that appear during the super-position of grid structures. Most widely recognisable in colour printing practices, generally viewed on screens (computer and TV they are in most cases examples of interference within a signal or a code, unwanted visual mis-alignment. Especially in digital image capture, moiré patternings appear when a geometrically even pattern, like a fabric or close-up of fine texture, has an appearance of rippled water with blue or red hues of concentric circle formations. The intriguing pattern formation in this case points back not only to the mis-alignment of frequencies, but can be further seen as the intersection point of a speculative ontology for the index of the digital image. Moiré not only as a visually reproducible phenomenon or effect, but a field of vision that blurs the boundaries between analogue and digital, perception and affect, manifesting the photographic as a constant site of becoming, a site of immanence. The philosophy of Henri Bergson, Brian Massumi and Francois Laruelle will be explored alongside the moiré image and phenomenon, to see if there is such a speculative site underlining the becoming of the digital image and its repercussions in contemporary digital culture.

Digital tissue and what it may reveal about the brain.

Science.gov (United States)

Morgan, Josh L; Lichtman, Jeff W

2017-10-30

Imaging as a means of scientific data storage has evolved rapidly over the past century from hand drawings, to photography, to digital images. Only recently can sufficiently large datasets be acquired, stored, and processed such that tissue digitization can actually reveal more than direct observation of tissue. One field where this transformation is occurring is connectomics: the mapping of neural connections in large volumes of digitized brain tissue.

Qualitative Evaluation of Digital Hand X-rays is Not a Reliable Method to Assess Bone Mineral Density

Directory of Open Access Journals (Sweden)

AndrewJ. Miller

2017-01-01

Full Text Available Object: The gold standard for evaluating bone mineral density is dual energy x-ray absorptiometry (DEXA.  Prior studies have shown poor reliability using analog wrist X-rays in diagnosing osteoporosis. Our goal was to investigate if there was improved diagnostic value to visual assessment of digital hand X-rays in osteoporosis screening. We hypothesized that similar to analog counterparts, digital hand X-rays have poor correlation and reliability in determining bone mineral density (BMD relative to DEXA.Methods: We prospectively evaluated female patients older than 65 years who presented to our hand clinic with digital hand and wrist X-rays as part of their evaluation over six months. Patients who had a fracture and were without DEXA scans within the past two years were excluded. Five fellowship-trained hand surgeons, blinded to DEXA T-scores, evaluated the x-rays over two assessments separated by four weeks and classified them as osteoporotic, osteopenic, or normal BMD.  Accuracy relative to DEXA T-score, interobserver and intraobserver rates were calculated.Results: Thirty four patients met the inclusion criteria and a total of 340 x-rays reviews were performed.  The assessments were correct in 169 cases (49% as compared to the DEXA T-scores. A mean weighted kappa coefficient of agreement between observers was 0.29 (range 0.02-0.41 reflecting a fair agreement. The first and second assessment for all five physicians was 0.46 (range 0.19-0.78 reflecting a moderate agreement.  Grouping osteoporosis and osteopenia together compared to normal, the accuracy, interobserver and intraobserver rates increased to 63%, 0.42 and 0.54 respectively.Conclusion: Abnormally low BMD is a common occurrence in patients treated for upper extremity disorders. There is poor accuracy relative to DEXA scan and only fair agreement in diagnosing osteoporosis using visual assessments of digital x-rays.

Surface Distresses Detection of Pavement Based on Digital Image Processing

OpenAIRE

Ouyang , Aiguo; Luo , Chagen; Zhou , Chao

2010-01-01

International audience; Pavement crack is the main form of early diseases of pavement. The use of digital photography to record pavement images and subsequent crack detection and classification has undergone continuous improvements over the past decade. Digital image processing has been applied to detect the pavement crack for its advantages of large amount of information and automatic detection. The applications of digital image processing in pavement crack detection, distresses classificati...

Hand and wrist arthritis of Behcet disease: Imaging features

International Nuclear Information System (INIS)

Sugawara, Shunsuke; Ehara, Shigeru; Hitachi, Shin; Sugimoto, Hideharu

2010-01-01

Background: Reports on arthritis in Behcet disease are relatively scarce, and imaging features vary. Purpose: To document the various imaging features of articular disorders of the hand and wrist in Behcet disease. Material and Methods: Four patients, four women aged 26 to 65 years, fulfilling the diagnostic criteria of Behcet disease, with imaging findings of hand and wrist arthritis, were seen in two institutions. Radiography and magnetic resonance (MR) imaging were studied to elucidate the pattern and distribution. Results: Both non-erosive arthritis and erosive arthritis of different features were noted: one with non-erosive synovitis of the wrist, one with wrist synovitis with minimal erosion, and two with erosive arthritis of the distal interphalangeal joint. Conclusion: Imaging manifestations of arthritis of Behcet disease vary, and may be similar to other seronegative arthritides

An Intelligent Web Digital Image Metadata Service Platform for Social Curation Commerce Environment

Directory of Open Access Journals (Sweden)

Seong-Yong Hong

2015-01-01

Full Text Available Information management includes multimedia data management, knowledge management, collaboration, and agents, all of which are supporting technologies for XML. XML technologies have an impact on multimedia databases as well as collaborative technologies and knowledge management. That is, e-commerce documents are encoded in XML and are gaining much popularity for business-to-business or business-to-consumer transactions. Recently, the internet sites, such as e-commerce sites and shopping mall sites, deal with a lot of image and multimedia information. This paper proposes an intelligent web digital image information retrieval platform, which adopts XML technology for social curation commerce environment. To support object-based content retrieval on product catalog images containing multiple objects, we describe multilevel metadata structures representing the local features, global features, and semantics of image data. To enable semantic-based and content-based retrieval on such image data, we design an XML-Schema for the proposed metadata. We also describe how to automatically transform the retrieval results into the forms suitable for the various user environments, such as web browser or mobile device, using XSLT. The proposed scheme can be utilized to enable efficient e-catalog metadata sharing between systems, and it will contribute to the improvement of the retrieval correctness and the user’s satisfaction on semantic-based web digital image information retrieval.

Image quality analysis of digital mammographic equipments

Energy Technology Data Exchange (ETDEWEB)

Mayo, P.; Pascual, A.; Verdu, G. [Valencia Univ. Politecnica, Chemical and Nuclear Engineering Dept. (Spain); Rodenas, F. [Valencia Univ. Politecnica, Applied Mathematical Dept. (Spain); Campayo, J.M. [Valencia Univ. Hospital Clinico, Servicio de Radiofisica y Proteccion Radiologica (Spain); Villaescusa, J.I. [Hospital Clinico La Fe, Servicio de Proteccion Radiologica, Valencia (Spain)

2006-07-01

The image quality assessment of a radiographic phantom image is one of the fundamental points in a complete quality control programme. The good functioning result of all the process must be an image with an appropriate quality to carry out a suitable diagnostic. Nowadays, the digital radiographic equipments are replacing the traditional film-screen equipments and it is necessary to update the parameters to guarantee the quality of the process. Contrast-detail phantoms are applied to digital radiography to study the threshold contrast detail sensitivity at operation conditions of the equipment. The phantom that is studied in this work is C.D.M.A.M. 3.4, which facilitates the evaluation of image contrast and detail resolution. One of the most extended indexes to measure the image quality in an objective way is the Image Quality Figure (I.Q.F.). This parameter is useful to calculate the image quality taking into account the contrast and detail resolution of the image analysed. The contrast-detail curve is useful as a measure of the image quality too, because it is a graphical representation in which the hole thickness and diameter are plotted for each contrast-detail combination detected in the radiographic image of the phantom. It is useful for the comparison of the functioning of different radiographic image systems, for phantom images under the same exposition conditions. The aim of this work is to study the image quality of different images contrast-detail phantom C.D.M.A.M. 3.4, carrying out the automatic detection of the contrast-detail combination and to establish a parameter which characterize in an objective way the mammographic image quality. This is useful to compare images obtained at different digital mammographic equipments to study the functioning of the equipments. (authors)

Image quality analysis of digital mammographic equipments

International Nuclear Information System (INIS)

Mayo, P.; Pascual, A.; Verdu, G.; Rodenas, F.; Campayo, J.M.; Villaescusa, J.I.

2006-01-01

The image quality assessment of a radiographic phantom image is one of the fundamental points in a complete quality control programme. The good functioning result of all the process must be an image with an appropriate quality to carry out a suitable diagnostic. Nowadays, the digital radiographic equipments are replacing the traditional film-screen equipments and it is necessary to update the parameters to guarantee the quality of the process. Contrast-detail phantoms are applied to digital radiography to study the threshold contrast detail sensitivity at operation conditions of the equipment. The phantom that is studied in this work is C.D.M.A.M. 3.4, which facilitates the evaluation of image contrast and detail resolution. One of the most extended indexes to measure the image quality in an objective way is the Image Quality Figure (I.Q.F.). This parameter is useful to calculate the image quality taking into account the contrast and detail resolution of the image analysed. The contrast-detail curve is useful as a measure of the image quality too, because it is a graphical representation in which the hole thickness and diameter are plotted for each contrast-detail combination detected in the radiographic image of the phantom. It is useful for the comparison of the functioning of different radiographic image systems, for phantom images under the same exposition conditions. The aim of this work is to study the image quality of different images contrast-detail phantom C.D.M.A.M. 3.4, carrying out the automatic detection of the contrast-detail combination and to establish a parameter which characterize in an objective way the mammographic image quality. This is useful to compare images obtained at different digital mammographic equipments to study the functioning of the equipments. (authors)

Fractal Image Coding with Digital Watermarks

Directory of Open Access Journals (Sweden)

Z. Klenovicova

2000-12-01

Full Text Available In this paper are presented some results of implementation of digitalwatermarking methods into image coding based on fractal principles. Thepaper focuses on two possible approaches of embedding digitalwatermarks into fractal code of images - embedding digital watermarksinto parameters for position of similar blocks and coefficients ofblock similarity. Both algorithms were analyzed and verified on grayscale static images.

Digital image correlation in analysis of striffness in local zones of welded joints

Czech Academy of Sciences Publication Activity Database

Milosevic, M.; Milosevic, N.J.; Sedmak, S.; Tatic, U.; Mitrovic, N.; Hloch, Sergej; Jovicic, R.

2016-01-01

Roč. 23, č. 1 (2016), s. 19-24 ISSN 1330-3651 Institutional support: RVO:68145535 Keywords : Aramis software * digital image correlation * strain analysis * stiffness * welded joints Subject RIV: JQ - Machines ; Tools Impact factor: 0.723, year: 2016 http://hrcak.srce.hr/file/225545

Hybrid phase retrieval algorithm for solving the twin image problem in in-line digital holography

Science.gov (United States)

Zhao, Jie; Wang, Dayong; Zhang, Fucai; Wang, Yunxin

2010-10-01

For the reconstruction in the in-line digital holography, there are three terms overlapping with each other on the image plane, named the zero order term, the real image and the twin image respectively. The unwanted twin image degrades the real image seriously. A hybrid phase retrieval algorithm is presented to address this problem, which combines the advantages of two popular phase retrieval algorithms. One is the improved version of the universal iterative algorithm (UIA), called the phase flipping-based UIA (PFB-UIA). The key point of this algorithm is to flip the phase of the object iteratively. It is proved that the PFB-UIA is able to find the support of the complicated object. Another one is the Fienup algorithm, which is a kind of well-developed algorithm and uses the support of the object as the constraint among the iteration procedure. Thus, by following the Fienup algorithm immediately after the PFB-UIA, it is possible to produce the amplitude and the phase distributions of the object with high fidelity. The primary simulated results showed that the proposed algorithm is powerful for solving the twin image problem in the in-line digital holography.

The impact of technical conditions of X-ray imaging on reproducibility and precision of digital computer-assisted X-ray radiogrammetry (DXR)

International Nuclear Information System (INIS)

Malich, A.; Boettcher, J.; Pfeil, A.; Sauner, D.; Heyne, J.P.; Petrovitch, A.; Hansch, A.; Kaiser, W.A.; Linss, W.

2004-01-01

To evaluate the reproducibility of imaging and analysis for bone mineral density (BMD) determination using digital computer-assisted X-ray radiogrammetry (DXR; Pronosco X-posure, version V.2, Sectra Pronosco, Denmark); to verify potential factors that influence BMD extrapolation such as tube voltage, film-focus distance (FFD), film quality and brand (Kodak T-MAT-Plus, Konika SRH, Agfa Scopix), imaging technology (conventional, digital), imaging system (Kodak, Agfa) and exposure level (mAs); and to clarify whether DXR analysis based on printouts of digital images is comparable to analysis of conventional images. The hand of a cadaver was X-rayed using varied parameters: 4-8 mAs, 40-52 kV, 90-130 cm FFD. Radiographs under standardised conditions were performed 10 times using a conventional machine (Philips Super 80 CP) and the printouts of a digital system (Digital Diagnost Philips Optimus) for the analysis of reproducibility. One image was scanned and analysed 10 times additionally for imaging reproducibility. Reliability error of the system for the imaging process using conventional radiographs-rays was 0.49% (standard conditions: 6 mAs, 40 kV, 1 m FFD), using printouts of digital images was 2.89% (4 mAs, 42 kV, 1 m FFD) and regarding the analysis process was 0.22%. BMD calculation is not affected by alterations in FFD (precision error 1.21%), mAs (0.83%) or film quality/brand (0.38%), but differs significantly depending on tube voltage (2.70%). The system was not able to analyse conventional images with tube voltages of 49/52 kV. DXR technology is stable with most of the tested parameters. Normative data should exclusively be used for calculations using similar tube voltage or correction factors. All other parameters had no significant influence on the BMD calculation. Reproducibility is high. For technical reasons it is not recommended to use the printouts of digital images for BMD determination. (orig.)

Comparison of image quality and radiation exposure from digital and 105-mm film images in pediatric fluoroscopy

International Nuclear Information System (INIS)

Drake, D.G.; Day, D.L.; Alford, B.A.; Geise, R.; Thompson, W.M.

1987-01-01

This study was designed to compare image quality of digitally acquired films compared with conventional 105-mm films in pediatric gastrointestinal and genitourinary fluoroscopic studies. Films were acquired digitally in 1,024 x 1,024 matrix, 512 x 512 matrix, and 105-mm film. Based on the observers' median scoring, the 1,024 x 1,024 reduced to 512 x 512 matrix provided similar overall image quality to the 105-mm films. The digital images produced a patient radiation exposure of 25% to 30% that of the 105-mm images on their equipment. The authors conclude that digital images provide similar image quality to 105-mm images with a significant reduction in patient radiation exposure

The role of hand drawing in basic design education in the digital age

NARCIS (Netherlands)

Have, R.; Van den Toorn, M.W.M.

2012-01-01

In the last decennia, hand drawing has been slowly moved out of the curricula in architecture schools and the teaching of computer skills has taken over. It has also created an 'intellectual dichotomy of viewpoints'; the digital and analogues. The question now is how to find a new balance for

Digital Image Watermarking in Transform Domains

International Nuclear Information System (INIS)

EL-Shazly, E.H.M.

2012-01-01

Fast development of internet and availability of huge digital content make it easy to create, modify and copy digital media such as audio, video and images. This causes a problem for owners of that content and hence a need to copy right protection tool was essential. First, encryption was proposed but it ensures protection during transmission only and once decryption occurred any one can modify the data. at that point watermarking was introduced as a solution to such problem. Watermarking is a process of inserting a low energy signal in to a high energy one so that it doesn't affect the main signal features. A good digital image watermarking technique should satisfy four requirements: 1) Embedding of a watermark should not degrade the host image visual quality (imperceptibility). 2) The embedded watermark should stick to the host image so that it couldn’t be removed by common image processing operation and could be extracted from the attacked watermarked image (robustness). 3) Knowing the embedding and extraction procedures is sufficient but not enough to extract the watermark; extra keys should be needed (security). 4) The watermarking technique should allow embedding and extraction of more than one watermark each independent of the other (capacity). This thesis presents a watermarking scheme that full fill the mentioned four requirements by jointing transform domains with Fractional Fourier Transform Domain (FracFT). More work on cascaded Discrete Wavelet Transform DWT with FracFT was done to develop a joint transform simply called Fractional Wavelet Transform (FWT). The proposed schemes were tested with different image processing attacks to verify its robustness. Finally, the watermarked image is transmitted over simulated MC CDMA channel to prove robustness in real transmission conditions case.

The clinical application of the digital imaging in urography

International Nuclear Information System (INIS)

Zhu Yuelong; Xie Sumin; Zhang Li; Li Huayu

2003-01-01

Objective: To evaluate the clinical application of the digital imaging in the urography. Methods: In total 112 patients underwent digital urography, including intravenous pyelography (IVP) in 38 cases and retrograde pyelography in 74 cases. Results: the entire urinary tract was better shown on digital imaging, which was accurate in locating the obstruction of urinary tract and helped the qualitative diagnosis. Digital urography was especially valuable in detecting urinary calculus. In 38 cases of IVP, the results were normal in 5 patients, renal stone in 12, ureteral stone in 13, ureteral stenosis in 6 and nephroblastom in 2. In the 74 cases of retrograde pyelography, benign ureteral stenosis was found in 31 patients, ureteral stone in 27, ureteral polyp in 2, urethral stone in 8 and benign urethral stenosis in 6. Conclusion: Digital imaging technique is of big value in the diagnosis of urinary tract lesions

Postoperative imaging of orthopaedic hardware in the hand and wrist: is there an added value for tomosynthesis?

Science.gov (United States)

De Silvestro, A; Martini, K; Becker, A S; Kim-Nguyen, T D L; Guggenberger, R; Calcagni, M; Frauenfelder, T

2018-02-01

To prospectively investigate digital tomosynthesis (DTS) as an alternative to digital radiography (DR) for postoperative imaging of orthopaedic hardware after trauma or arthrodesis in the hand and wrist. Thirty-six consecutive patients (12 female, median age 36 years, range 19-86 years) were included in this institutional review board approved clinical trial. Imaging was performed with DTS in dorso-palmar projection and DR was performed in dorso-palmar, lateral, and oblique views. Images were evaluated by two independent radiologists for qualitative and diagnosis-related imaging parameters using a four-point Likert scale (1=excellent, 4not diagnostic) and nominal scale. Interobserver agreement between the two readers was assessed with Cohen's kappa (k). Differences between DTS and CR were tested with Wilcoxon's signed-rank test. A p-value <0.05 was considered statistically significant. Regarding image quality, interobserver agreement was higher for DTS compared to DR, especially for fracture-related parameters (delineation osteosynthesis material [OSM]: K DTS 0.96 versus K DR 0.45; delineation fracture margins: K DTS 0.78 versus K DR 0.35). Delineation of fracture margins and delineation of adjacent joint spaces scored significant better for DTS compared to DR (delineation fracture margins: DTS1.54, DR2.28, p0.001; delineation adjacent joint spaces: DTS1.31, DR2.24, p0.001). Regarding diagnosis-related findings, interobserver agreement was almost equal. DTS showed a significant higher sharpness of fracture margins (DTS1.94, DR2.33, p0.04). Mean dose area product (DAP) for DTS was significant higher compared to DR (mean DR0.219 Gy·cm 2 , mean DTS0.903 Gy·cm 2 , p0.001). Fracture healing is more visible and interobserver agreement is higher for DTS compared to DR in the postoperative assessment of orthopaedic hardware in the hand and wrist. Copyright © 2017 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

Integrating digital topology in image-processing libraries.

Science.gov (United States)

Lamy, Julien

2007-01-01

This paper describes a method to integrate digital topology informations in image-processing libraries. This additional information allows a library user to write algorithms respecting topological constraints, for example, a seed fill or a skeletonization algorithm. As digital topology is absent from most image-processing libraries, such constraints cannot be fulfilled. We describe and give code samples for all the structures necessary for this integration, and show a use case in the form of a homotopic thinning filter inside ITK. The obtained filter can be up to a hundred times as fast as ITK's thinning filter and works for any image dimension. This paper mainly deals of integration within ITK, but can be adapted with only minor modifications to other image-processing libraries.

Better imaging: the advantages of digital radiography

NARCIS (Netherlands)

van der Stelt, P.F.

2008-01-01

Background. Digital radiography has been available in dentistry for more than 25 years, but it has not replaced conventional film-based radiography completely. This could be because of the costs involved in replacing conventional radiographic equipment with a digital imaging system, or because

Principles of digital image synthesis

CERN Document Server

Glassner, Andrew S

1995-01-01

Image synthesis, or rendering, is a field of transformation: it changesgeometry and physics into meaningful images. Because the most popularalgorithms frequently change, it is increasingly important for researchersand implementors to have a basic understanding of the principles of imagesynthesis. Focusing on theory, Andrew Glassner provides a comprehensiveexplanation of the three core fields of study that come together to formdigital image synthesis: the human visual system, digital signalprocessing, and the interaction of matter and light. Assuming no more thana basic background in calculus,

Practical evaluation of clinical image quality (4). Determination of image quality in digital radiography system

International Nuclear Information System (INIS)

Katayama, Reiji

2016-01-01

Recently, for medical imaging, digital radiography systems are widely used in clinical practices. However, a study in the past reported that a patient radiation exposure level by digital radiography is in fact not lower than that by analog radiography system. High level of attention needs to be paid for over-exposure when using the conventional analog radiography with a screen and a film, as it results in high density of the film. However, for digital radiography systems, since the automatic adjusting function of image density is equipped with them, no attention for radiation dose need to be paid. Thus technologists tend to be careless and results in higher chance for over-exposure. Current digital radiography systems are high-performance in the image properties and capable of patient dose reduction. Especially, the image quality of the flat panel detector system is recognized, higher than that of the computed radiography system by imaging plates, in both objective and subjective evaluations. Therefore, we technologists are responsible for optimizing the balance between the image quality of the digital radiogram and the radiation dose required for each case. Moreover, it is also required for us as medical technologists to make effective use of such evaluation result of medical images for patients. (author)

Digital image processing in neutron radiography

International Nuclear Information System (INIS)

Koerner, S.

2000-11-01

Neutron radiography is a method for the visualization of the macroscopic inner-structure and material distributions of various samples. The basic experimental arrangement consists of a neutron source, a collimator functioning as beam formatting assembly and of a plane position sensitive integrating detector. The object is placed between the collimator exit and the detector, which records a two dimensional image. This image contains information about the composition and structure of the sample-interior, as a result of the interaction of neutrons by penetrating matter. Due to rapid developments of detector and computer technology as well as deployments in the field of digital image processing, new technologies are nowadays available which have the potential to improve the performance of neutron radiographic investigations enormously. Therefore, the aim of this work was to develop a state-of-the art digital imaging device, suitable for the two neutron radiography stations located at the 250 kW TRIGA Mark II reactor at the Atominstitut der Oesterreichischen Universitaeten and furthermore, to identify and develop two and three dimensional digital image processing methods suitable for neutron radiographic and tomographic applications, and to implement and optimize them within data processing strategies. The first step was the development of a new imaging device fulfilling the requirements of a high reproducibility, easy handling, high spatial resolution, a large dynamic range, high efficiency and a good linearity. The detector output should be inherently digitized. The key components of the detector system selected on the basis of these requirements consist of a neutron sensitive scintillator screen, a CCD-camera and a mirror to reflect the light emitted by the scintillator to the CCD-camera. This detector design enables to place the camera out of the direct neutron beam. The whole assembly is placed in a light shielded aluminum box. The camera is controlled by a

Digital image processing in neutron radiography

International Nuclear Information System (INIS)

Koerner, S.

2000-11-01

Neutron radiography is a method for the visualization of the macroscopic inner-structure and material distributions of various materials. The basic experimental arrangement consists of a neutron source, a collimator functioning as beam formatting assembly and of a plane position sensitive integrating detector. The object is placed between the collimator exit and the detector, which records a two dimensional image. This image contains information about the composition and structure of the sample-interior, as a result of the interaction of neutrons by penetrating matter. Due to rapid developments of detector and computer technology as well as deployments in the field of digital image processing, new technologies are nowadays available which have the potential to improve the performance of neutron radiographic investigations enormously. Therefore, the aim of this work was to develop a state-of-the art digital imaging device, suitable for the two neutron radiography stations located at the 250 kW TRIGA Mark II reactor at the Atominstitut der Oesterreichischen Universitaeten and furthermore, to identify and develop two and three dimensional digital image processing methods suitable for neutron radiographic and tomographic applications, and to implement and optimize them within data processing strategies. The first step was the development of a new imaging device fulfilling the requirements of a high reproducibility, easy handling, high spatial resolution, a large dynamic range, high efficiency and a good linearity. The detector output should be inherently digitized. The key components of the detector system selected on the basis of these requirements consist of a neutron sensitive scintillator screen, a CCD-camera and a mirror to reflect the light emitted by the scintillator to the CCD-camera. This detector design enables to place the camera out of the direct neutron beam. The whole assembly is placed in a light shielded aluminum box. The camera is controlled by a

Detecting jaundice by using digital image processing

Science.gov (United States)

Castro-Ramos, J.; Toxqui-Quitl, C.; Villa Manriquez, F.; Orozco-Guillen, E.; Padilla-Vivanco, A.; Sánchez-Escobar, JJ.

2014-03-01

When strong Jaundice is presented, babies or adults should be subject to clinical exam like "serum bilirubin" which can cause traumas in patients. Often jaundice is presented in liver disease such as hepatitis or liver cancer. In order to avoid additional traumas we propose to detect jaundice (icterus) in newborns or adults by using a not pain method. By acquiring digital images in color, in palm, soles and forehead, we analyze RGB attributes and diffuse reflectance spectra as the parameter to characterize patients with either jaundice or not, and we correlate that parameters with the level of bilirubin. By applying support vector machine we distinguish between healthy and sick patients.

Desktop publishing and medical imaging: paper as hardcopy medium for digital images.

Science.gov (United States)

Denslow, S

1994-08-01

Desktop-publishing software and hardware has progressed to the point that many widely used word-processing programs are capable of printing high-quality digital images with many shades of gray from black to white. Accordingly, it should be relatively easy to print digital medical images on paper for reports, instructional materials, and in research notes. Components were assembled that were necessary for extracting image data from medical imaging devices and converting the data to a form usable by word-processing software. A system incorporating these components was implemented in a medical setting and has been operating for 18 months. The use of this system by medical staff has been monitored.

Investigation of physical imaging properties in various digital radiography systems

Energy Technology Data Exchange (ETDEWEB)

Jeong, Hoi Woun [Dept. of Radiological Science, Baekseok Culture University, Cheonan (Korea, Republic of); Min, Jung Hwan [Dept. of Radiological technology, Shingu University, Seongnam (Korea, Republic of); Yoon, Yong Su [Dept. of Health Sciences, Graduate School of Medical Sciences, Kyushu University, Kyushu (Japan); Kim, Jung Min [Dept. of Health and Environmental Science, College of Health Science, Korea University, Seoul (Korea, Republic of)

2017-09-15

We aimed to evaluate the physical imaging properties in various digital radiography systems with charged coupled device (CCD), computed radiography (CR), and indirect flat panel detector (FPD). The imaging properties measured in this study were modulation transfer function (MTF) wiener spectrum (WS), and detective quantum efficiency (DQE) to compare the performance of each digital radiography system. The system response of CCD were in a linear relationship with exposure and that of CR and FPD were proportional to the logarithm of exposure. The MTF of both CR and FPD indicated a similar tendency but in case of CCD, it showed lower MTF than that of CR and FPD. FPD showed the lowest WS and also indicated the highest DQE among three systems. According to the results, digital radiography system with different type of image receptor had its own image characteristics. Therefore, it is important to know the physical imaging characteristics of the digital radiography system accurately to obtain proper image quality.

The effects of gray scale image processing on digital mammography interpretation performance.

Science.gov (United States)

Cole, Elodia B; Pisano, Etta D; Zeng, Donglin; Muller, Keith; Aylward, Stephen R; Park, Sungwook; Kuzmiak, Cherie; Koomen, Marcia; Pavic, Dag; Walsh, Ruth; Baker, Jay; Gimenez, Edgardo I; Freimanis, Rita

2005-05-01

To determine the effects of three image-processing algorithms on diagnostic accuracy of digital mammography in comparison with conventional screen-film mammography. A total of 201 cases consisting of nonprocessed soft copy versions of the digital mammograms acquired from GE, Fischer, and Trex digital mammography systems (1997-1999) and conventional screen-film mammograms of the same patients were interpreted by nine radiologists. The raw digital data were processed with each of three different image-processing algorithms creating three presentations-manufacturer's default (applied and laser printed to film by each of the manufacturers), MUSICA, and PLAHE-were presented in soft copy display. There were three radiologists per presentation. Area under the receiver operating characteristic curve for GE digital mass cases was worse than screen-film for all digital presentations. The area under the receiver operating characteristic for Trex digital mass cases was better, but only with images processed with the manufacturer's default algorithm. Sensitivity for GE digital mass cases was worse than screen film for all digital presentations. Specificity for Fischer digital calcifications cases was worse than screen film for images processed in default and PLAHE algorithms. Specificity for Trex digital calcifications cases was worse than screen film for images processed with MUSICA. Specific image-processing algorithms may be necessary for optimal presentation for interpretation based on machine and lesion type.

Digital image intensifier radiography. One year's experience with a Polytron system

International Nuclear Information System (INIS)

Busch, H.P.; Lehmann, K.J.; Georgi, M.

1989-01-01

Since January 1988, digital image intensifier radiography has been used in the Clinic in Mannheim for DSA examinations and also in place of conventional screen/film examinations. Measurements have shown that compared with 100 mm and film/screen formats, digital radiography has poorer spatial resolution, but improved contrast resolution. The most common use of digital radiography was for examinations of the gastrointestinal tract. Using the demonstration of the mucosal fine relief pattern as a criterion of image quality, digital image intensifier radiography was able to achieve this satisfactorily. Comparison with film/screen examinations showed no loss of diagnostic information. Advantages of image intensifier radiography are reduced radiation dose, the possibility of postprocessing and economy. On the basis of 399 examinations, digital image intensifier radiography is now firmly established as part of the daily routine of the Mannheim Clinic. (orig.) [de

Quantity and Quality of Support for Digital Engagement

NARCIS (Netherlands)

van Deursen, Alexander Johannes Aloysius Maria; Helsper, Ellen

2016-01-01

Following the course taking by digital divide or digital inclusion research, this paper uses socio-cultural, socio-economic, social, and digital indicators to predict access to and the type of potential and actual social support networks that might help an individual in using the Internet. In

Implementation of a dedicated digital projectional radiographic system in thoracic imaging

International Nuclear Information System (INIS)

Aberle, D.R.; Batra, P.; Hayrapetian, A.S.; Brown, K.; Morioka, C.A.; Steckel, R.J.

1988-01-01

An integrated digital radiographic system was evaluated with respect to image quality and impact on diagnosis relative to conventional chest radiographs for a variety of focal and diffuse lung processes. Digital images were acquired with a stimulable phosphor plate detector that was scanned by a semiconductor laser for immediate digitalization to a 2,048 X 2,464 X 10-bit image. Digital images were displayed on a 2,048-line monitor and printed on 14 X 17-inch film with use of a laser film printer (Kodak). Preliminary results with this system, including the effects of user interaction with the display monitor, inverse intensity display, and regional magnification techniques, indicate that it may be successfully implemented for thoracic imaging

Observation of Compressive Deformation Behavior of Nuclear Graphite by Digital Image Correlation

International Nuclear Information System (INIS)

Kim, Hyunju; Kim, Eungseon; Kim, Minhwan; Kim, Yongwan

2014-01-01

Polycrystalline nuclear graphite has been proposed as a fuel element, moderator and reflector blocks, and core support structures in a very high temperature gas-cooled reactor. During reactor operation, graphite core components and core support structures are subjected to various stresses. It is therefore important to understand the mechanism of deformation and fracture of nuclear graphites, and their significance to structural integrity assessment methods. Digital image correlation (DIC) is a powerful tool to measure the full field displacement distribution on the surface of the specimens. In this study, to gain an understanding of compressive deformation characteristic, the formation of strain field during a compression test was examined using a commercial DIC system. An examination was made to characterize the compressive deformation behavior of nuclear graphite by a digital image correlation. The non-linear load-displacement characteristic prior to the peak load was shown to be mainly dominated by the presence of localized strains, which resulted in a permanent displacement. Young's modulus was properly calculated from the measured strain

Giant cell tumor of the tendon sheath of the hand - magnetic resonance image and orthopaedic treatment

International Nuclear Information System (INIS)

Kirova, G.; Monovska, T.; Jablanski, V.; Alexieva, K.; Velev, M.

2009-01-01

Giant cell tumour of the tendon sheath (GCT-TS), also known as localized nodular tenosynovitis, is a benign neoplasm that occurs dominantly on the digits. These tumours most commonly occur in patients aged 30-50 years and are associated with degenerative joint disease. GCT-TS usually arises from the synovium of tendon sheets, affecting interfalangeal joints of the hand, feet, ankle and knees. Magnetic Resonance Imaging is able to depict characteristic signal intensities and can accurately assess the tumor size and degree of extent around the phalanx. We present a case of a 36 years-old male patient with GCT-TS in the flexor tendon of his left second finger, diagnosed with Magnetic Resonance imaging. The mass was excised widely with preservation of the flexor tendon without recurrence. (authors)

Integrating Digital Images into the Art and Art History Curriculum.

Science.gov (United States)

Pitt, Sharon P.; Updike, Christina B.; Guthrie, Miriam E.

2002-01-01

Describes an Internet-based image database system connected to a flexible, in-class teaching and learning tool (the Madison Digital Image Database) developed at James Madison University to bring digital images to the arts and humanities classroom. Discusses content, copyright issues, ensuring system effectiveness, instructional impact, sharing the…

Photography/Digital Imaging: Parallel & Paradoxical Histories.

Science.gov (United States)

Witte, Mary Stieglitz

With the introduction of photography and photomechanical printing processes in the 19th century, the first age of machine pictures and reproductions emerged. The 20th century introduced computer image processing systems, creating a digital imaging revolution. Rather than concentrating on the adversarial aspects of the computer's influence on…

Analysis of identification of digital images from a map of cosmic microwaves

Science.gov (United States)

Skeivalas, J.; Turla, V.; Jurevicius, M.; Viselga, G.

2018-04-01

This paper discusses identification of digital images from the cosmic microwave background radiation map formed according to the data of the European Space Agency "Planck" telescope by applying covariance functions and wavelet theory. The estimates of covariance functions of two digital images or single images are calculated according to the random functions formed of the digital images in the form of pixel vectors. The estimates of pixel vectors are formed on expansion of the pixel arrays of the digital images by a single vector. When the scale of a digital image is varied, the frequencies of single-pixel color waves remain constant and the procedure for calculation of covariance functions is not affected. For identification of the images, the RGB format spectrum has been applied. The impact of RGB spectrum components and the color tensor on the estimates of covariance functions was analyzed. The identity of digital images is assessed according to the changes in the values of the correlation coefficients in a certain range of values by applying the developed computer program.

Digital Radiology Image Learning Library

International Nuclear Information System (INIS)

Arenson, R.L.; Greenes, R.; Allman, R.; Swett, H.

1989-01-01

The Digital Radiology Image Learning Library (DRILL) is designed as an interactive teaching tool targeted to the radiologic community. The DRILL pilot comprises a comprehensive mammographic information base consisting of factual data in a relational database, an extensive knowledge base in semantic nets and high-resolution images. A flexible query module permits the user to browse and retrieve examination data, case discussions, and related images. Other applications, including expert systems, instructional programs, and skill building exercises, can be accessed through well-defined software constructs

Digital Shaded-Relief Image of Alaska

Science.gov (United States)

Riehle, J.R.; Fleming, Michael D.; Molnia, B.F.; Dover, J.H.; Kelley, J.S.; Miller, M.L.; Nokleberg, W.J.; Plafker, George; Till, A.B.

1997-01-01

Introduction One of the most spectacular physiographic images of the conterminous United States, and the first to have been produced digitally, is that by Thelin and Pike (USGS I-2206, 1991). The image is remarkable for its crispness of detail and for the natural appearance of the artificial land surface. Our goal has been to produce a shaded-relief image of Alaska that has the same look and feel as the Thelin and Pike image. The Alaskan image could have been produced at the same scale as its lower 48 counterpart (1:3,500,000). But by insetting the Aleutian Islands into the Gulf of Alaska, we were able to print the Alaska map at a larger scale (1:2,500,000) and about the same physical size as the Thelin and Pike image. Benefits of the 1:2,500,000 scale are (1) greater resolution of topographic features and (2) ease of reference to the U.S. Geological Survey (USGS) (1987) Alaska Map E and the statewide geologic map (Beikman, 1980), which are both 1:2,500,000 scale. Manually drawn, shaded-relief images of Alaska's land surface have long been available (for example, Department of the Interior, 1909; Raisz, 1948). The topography depicted on these early maps is mainly schematic. Maps showing topographic contours were first available for the entire State in 1953 (USGS, 1:250,000) (J.H. Wittmann, USGS, written commun., 1996). The Alaska Map E was initially released in 1954 in both planimetric (revised in 1973 and 1987) and shaded-relief versions (revised in 1973, 1987, and 1996); topography depicted on the shaded-relief version is based on the 1:250,000-scale USGS topographic maps. Alaska Map E was later modified to include hypsometric tinting by Raven Maps and Images (1989, revised 1993) as copyrighted versions. Other shaded-relief images were produced for The National Geographic Magazine (LaGorce, 1956; 1:3,000,000) or drawn by Harrison (1970; 1:7,500,000) for The National Atlas of the United States. Recently, the State of Alaska digitally produced a shaded-relief image

Finite element formulation for a digital image correlation method

International Nuclear Information System (INIS)

Sun Yaofeng; Pang, John H. L.; Wong, Chee Khuen; Su Fei

2005-01-01

A finite element formulation for a digital image correlation method is presented that will determine directly the complete, two-dimensional displacement field during the image correlation process on digital images. The entire interested image area is discretized into finite elements that are involved in the common image correlation process by use of our algorithms. This image correlation method with finite element formulation has an advantage over subset-based image correlation methods because it satisfies the requirements of displacement continuity and derivative continuity among elements on images. Numerical studies and a real experiment are used to verify the proposed formulation. Results have shown that the image correlation with the finite element formulation is computationally efficient, accurate, and robust

[Managing digital medical imaging projects in healthcare services: lessons learned].

Science.gov (United States)

Rojas de la Escalera, D

2013-01-01

Medical imaging is one of the most important diagnostic instruments in clinical practice. The technological development of digital medical imaging has enabled healthcare services to undertake large scale projects that require the participation and collaboration of many professionals of varied backgrounds and interests as well as substantial investments in infrastructures. Rather than focusing on systems for dealing with digital medical images, this article deals with the management of projects for implementing these systems, reviewing various organizational, technological, and human factors that are critical to ensure the success of these projects and to guarantee the compatibility and integration of digital medical imaging systems with other health information systems. To this end, the author relates several lessons learned from a review of the literature and the author's own experience in the technical coordination of digital medical imaging projects. Copyright © 2012 SERAM. Published by Elsevier Espana. All rights reserved.

Digital image processing of mandibular trabeculae on radiographs

Energy Technology Data Exchange (ETDEWEB)

Ogino, Toshi

1987-06-01

The present study was aimed to reveal the texture patterns of the radiographs of the mandibular trabeculae by digital image processing. The 32 cases of normal subjects and the 13 cases of patients with mandibular diseases of ameloblastoma, primordial cysts, squamous cell carcinoma and odontoma were analyzed by their intra-oral radiographs in the right premolar regions. The radiograms were digitized by the use of a drum scanner densitometry method. The input radiographic images were processed by a histogram equalization method. The result are as follows : First, the histogram equalization method enhances the image contrast of the textures. Second, the output images of the textures for normal mandible-trabeculae radiograms are of network pattern in nature. Third, the output images for the patients are characterized by the non-network pattern and replaced by the patterns of the fabric texture, intertwined plants (karakusa-pattern), scattered small masses and amorphous texture. Thus, these results indicates that the present digital image system is expected to be useful for revealing the texture patterns of the radiographs and in the future for the texture analysis of the clinical radiographs to obtain quantitative diagnostic findings.

Contactless and pose invariant biometric identification using hand surface.

Science.gov (United States)

Kanhangad, Vivek; Kumar, Ajay; Zhang, David

2011-05-01

This paper presents a novel approach for hand matching that achieves significantly improved performance even in the presence of large hand pose variations. The proposed method utilizes a 3-D digitizer to simultaneously acquire intensity and range images of the user's hand presented to the system in an arbitrary pose. The approach involves determination of the orientation of the hand in 3-D space followed by pose normalization of the acquired 3-D and 2-D hand images. Multimodal (2-D as well as 3-D) palmprint and hand geometry features, which are simultaneously extracted from the user's pose normalized textured 3-D hand, are used for matching. Individual matching scores are then combined using a new dynamic fusion strategy. Our experimental results on the database of 114 subjects with significant pose variations yielded encouraging results. Consistent (across various hand features considered) performance improvement achieved with the pose correction demonstrates the usefulness of the proposed approach for hand based biometric systems with unconstrained and contact-free imaging. The experimental results also suggest that the dynamic fusion approach employed in this work helps to achieve performance improvement of 60% (in terms of EER) over the case when matching scores are combined using the weighted sum rule.

Higuchi dimension of digital images.

Directory of Open Access Journals (Sweden)

Helmut Ahammer

Full Text Available There exist several methods for calculating the fractal dimension of objects represented as 2D digital images. For example, Box counting, Minkowski dilation or Fourier analysis can be employed. However, there appear to be some limitations. It is not possible to calculate only the fractal dimension of an irregular region of interest in an image or to perform the calculations in a particular direction along a line on an arbitrary angle through the image. The calculations must be made for the whole image. In this paper, a new method to overcome these limitations is proposed. 2D images are appropriately prepared in order to apply 1D signal analyses, originally developed to investigate nonlinear time series. The Higuchi dimension of these 1D signals is calculated using Higuchi's algorithm, and it is shown that both regions of interests and directional dependencies can be evaluated independently of the whole picture. A thorough validation of the proposed technique and a comparison of the new method to the Fourier dimension, a common two dimensional method for digital images, are given. The main result is that Higuchi's algorithm allows a direction dependent as well as direction independent analysis. Actual values for the fractal dimensions are reliable and an effective treatment of regions of interests is possible. Moreover, the proposed method is not restricted to Higuchi's algorithm, as any 1D method of analysis, can be applied.

Benefits and unexpected artifacts of biplanar digital slot-scanning imaging in children

Energy Technology Data Exchange (ETDEWEB)

Blumer, Steven L. [Nemours/A.I duPont Hospital for Children, Department of Medical Imaging, Wilmington, DE (United States); Dinan, David [Nemours Children' s Hospital, Orlando, FL (United States); Grissom, Leslie E. [Nemours/Alfred I. duPont Hospital for Children, Department of Radiology, Wilmington, DE (United States)

2014-07-15

Biplanar digital slot-scanning allows for relatively low-dose orthopedic imaging, an advantage in imaging children given the growing concerns regarding radiosensitivity. We have used this system for approximately 1 year for orthopedic imaging of the spine and lower extremities. We have noted advantages of using the digital slot-scanning system when compared with computed radiographic and standard digital radiographic imaging systems, but we also found unexpected but common imaging artifacts that are the direct result of the imaging method and that have not been reported. This pictorial essay serves to familiarize radiologists with the advantages of the digital slot-scanning system as well as imaging artifacts common with this new technology. (orig.)

Digital Imaging and Communications in Medicine Whole Slide Imaging Connectathon at Digital Pathology Association Pathology Visions 2017.

Science.gov (United States)

Clunie, David; Hosseinzadeh, Dan; Wintell, Mikael; De Mena, David; Lajara, Nieves; Garcia-Rojo, Marcial; Bueno, Gloria; Saligrama, Kiran; Stearrett, Aaron; Toomey, David; Abels, Esther; Apeldoorn, Frank Van; Langevin, Stephane; Nichols, Sean; Schmid, Joachim; Horchner, Uwe; Beckwith, Bruce; Parwani, Anil; Pantanowitz, Liron

2018-01-01

As digital pathology systems for clinical diagnostic work applications become mainstream, interoperability between these systems from different vendors becomes critical. For the first time, multiple digital pathology vendors have publicly revealed the use of the digital imaging and communications in medicine (DICOM) standard file format and network protocol to communicate between separate whole slide acquisition, storage, and viewing components. Note the use of DICOM for clinical diagnostic applications is still to be validated in the United States. The successful demonstration shows that the DICOM standard is fundamentally sound, though many lessons were learned. These lessons will be incorporated as incremental improvements in the standard, provide more detailed profiles to constrain variation for specific use cases, and offer educational material for implementers. Future Connectathon events will expand the scope to include more devices and vendors, as well as more ambitious use cases including laboratory information system integration and annotation for image analysis, as well as more geographic diversity. Users should request DICOM features in all purchases and contracts. It is anticipated that the growth of DICOM-compliant manufacturers will likely also ease DICOM for pathology becoming a recognized standard and as such the regulatory pathway for digital pathology products.

Hands-off and hands-on casting consistency of amputee below knee sockets using magnetic resonance imaging.

Science.gov (United States)

Safari, Mohammad Reza; Rowe, Philip; McFadyen, Angus; Buis, Arjan

2013-01-01

Residual limb shape capturing (Casting) consistency has a great influence on the quality of socket fit. Magnetic Resonance Imaging was used to establish a reliable reference grid for intercast and intracast shape and volume consistency of two common casting methods, Hands-off and Hands-on. Residual limbs were cast for twelve people with a unilateral below knee amputation and scanned twice for each casting concept. Subsequently, all four volume images of each amputee were semiautomatically segmented and registered to a common coordinate system using the tibia and then the shape and volume differences were calculated. The results show that both casting methods have intra cast volume consistency and there is no significant volume difference between the two methods. Inter- and intracast mean volume differences were not clinically significant based on the volume of one sock criteria. Neither the Hands-off nor the Hands-on method resulted in a consistent residual limb shape as the coefficient of variation of shape differences was high. The resultant shape of the residual limb in the Hands-off casting was variable but the differences were not clinically significant. For the Hands-on casting, shape differences were equal to the maximum acceptable limit for a poor socket fit.

Making cytological diagnoses on digital images using the iPath network.

Science.gov (United States)

Dalquen, Peter; Savic Prince, Spasenija; Spieler, Peter; Kunze, Dietmar; Neumann, Heinrich; Eppenberger-Castori, Serenella; Adams, Heiner; Glatz, Katharina; Bubendorf, Lukas

2014-01-01

The iPath telemedicine platform Basel is mainly used for histological and cytological consultations, but also serves as a valuable learning tool. To study the level of accuracy in making diagnoses based on still images achieved by experienced cytopathologists, to identify limiting factors, and to provide a cytological image series as a learning set. Images from 167 consecutive cytological specimens of different origin were uploaded on the iPath platform and evaluated by four cytopathologists. Only wet-fixed and well-stained specimens were used. The consultants made specific diagnoses and categorized each as benign, suspicious or malignant. For all consultants, specificity and sensitivity regarding categorized diagnoses were 83-92 and 85-93%, respectively; the overall accuracy was 88-90%. The interobserver agreement was substantial (κ = 0.791). The lowest rate of concordance was achieved in urine and bladder washings and in the identification of benign lesions. Using a digital image set for diagnostic purposes implies that even under optimal conditions the accuracy rate will not exceed to 80-90%, mainly because of lacking supportive immunocytochemical or molecular tests. This limitation does not disqualify digital images for teleconsulting or as a learning aid. The series of images used for the study are open to the public at http://pathorama.wordpress.com/extragenital-cytology-2013/. © 2014 S. Karger AG, Basel.

Tomosynthesis and contrast-enhanced digital mammography: recent advances in digital mammography

International Nuclear Information System (INIS)

Diekmann, Felix; Bick, Ulrich

2007-01-01

Digital mammography is more and more replacing conventional mammography. Initial concerns about an inferior image quality of digital mammography have been largely overcome and recent studies even show digital mammography to be superior in women with dense breasts, while at the same time reducing radiation exposure. Nevertheless, an important limitation of digital mammography remains: namely, the fact that summation may obscure lesions in dense breast tissue. However, digital mammography offers the option of so-called advanced applications, and two of these, contrast-enhanced mammography and tomosynthesis, are promising candidates for improving the detection of breast lesions otherwise obscured by the summation of dense tissue. Two techniques of contrast-enhanced mammography are available: temporal subtraction of images acquired before and after contrast administration and the so-called dual-energy technique, which means that pairs of low/high-energy images acquired after contrast administration are subtracted. Tomosynthesis on the other hand provides three-dimensional information on the breast. The images are acquired with different angulations of the X-ray tube while the object or detector is static. Various reconstruction algorithms can then be applied to the set of typically nine to 28 source images to reconstruct 1-mm slices with a reduced risk of obscuring pathology. Combinations of both advanced applications have only been investigated in individual experimental studies; more advanced software algorithms and CAD systems are still in their infancy and have only undergone preliminary clinical evaluation. (orig.)

Development of an image intensifier-TV digital imaging system with a multiple-slit scanning x-ray beam

International Nuclear Information System (INIS)

Kume, Y.; Doi, K.

1986-01-01

The authors are developing a new digital x-ray imaging system employing a multiple-slit assembly (MSA) and an image intensifier (II)-TV digital system. The final image consisting of primary radiation is digitally reconstructed from multiple slit images obtained with the MSA. This system can significantly reduce the scattered radiation from an object and the veiling glare from II-TV system. The quality of the reconstructed image is related to many parameters, such as slit width, the number of image frames, and the image reconstruction algorithm. They present the effect of these various parameters on basic imaging properties and the practicability of the method in comparison with conventional wide beam imaging

A generic, time-resolved, integrated digital image correlation, identification approach

NARCIS (Netherlands)

Hoefnagels, J.P.M.; Neggers, J.; Blaysat, Benoît; Hild, François; Geers, M.G.D.; Jin, H.; Sciammarella, C.; Yoshida, S.; Lamberti, L.

2015-01-01

A generic one-step Integrated Digital Image Correlation (I-DIC) inverse parameter identification approach is introduced that enables direct identification of constitutive model parameters by intimately integrating a Finite Elements Method (FEM) with Digital Image Correlation (DIC), directly

Image analysis and machine learning in digital pathology: Challenges and opportunities.

Science.gov (United States)

Madabhushi, Anant; Lee, George

2016-10-01

With the rise in whole slide scanner technology, large numbers of tissue slides are being scanned and represented and archived digitally. While digital pathology has substantial implications for telepathology, second opinions, and education there are also huge research opportunities in image computing with this new source of "big data". It is well known that there is fundamental prognostic data embedded in pathology images. The ability to mine "sub-visual" image features from digital pathology slide images, features that may not be visually discernible by a pathologist, offers the opportunity for better quantitative modeling of disease appearance and hence possibly improved prediction of disease aggressiveness and patient outcome. However the compelling opportunities in precision medicine offered by big digital pathology data come with their own set of computational challenges. Image analysis and computer assisted detection and diagnosis tools previously developed in the context of radiographic images are woefully inadequate to deal with the data density in high resolution digitized whole slide images. Additionally there has been recent substantial interest in combining and fusing radiologic imaging and proteomics and genomics based measurements with features extracted from digital pathology images for better prognostic prediction of disease aggressiveness and patient outcome. Again there is a paucity of powerful tools for combining disease specific features that manifest across multiple different length scales. The purpose of this review is to discuss developments in computational image analysis tools for predictive modeling of digital pathology images from a detection, segmentation, feature extraction, and tissue classification perspective. We discuss the emergence of new handcrafted feature approaches for improved predictive modeling of tissue appearance and also review the emergence of deep learning schemes for both object detection and tissue classification

Digital-image processing improves man-machine communication at a nuclear reactor

International Nuclear Information System (INIS)

Cook, S.A.; Harrington, T.P.; Toffer, H.

1982-01-01

The application of digital image processing to improve man-machine communication in a nuclear reactor control room is illustrated. At the Hanford N Reactor, operated by UNC Nuclear Industries for the United States Department of Energy, in Richland, Washington, digital image processing is applied to flow, temperature, and tube power data. Color displays are used to present the data in a clear and concise fashion. Specific examples are used to demonstrate the capabilities and benefits of digital image processing of reactor data. N Reactor flow and power maps for routine reactor operations and for perturbed reactor conditions are displayed. The advantages of difference mapping are demonstrated. Image processing techniques have also been applied to results of analytical reactor models; two examples are shown. The potential of combining experimental and analytical information with digital image processing to produce predictive and adaptive reactor core models is discussed. The applications demonstrate that digital image processing can provide new more effective ways for control room personnel to assess reactor status, to locate problems and explore corrective actions. 10 figures

ASTM reference radiologic digital image standards

International Nuclear Information System (INIS)

Wysnewski, R.; Wysnewski, D.

1996-01-01

ASTM Reference Radiographs have been essential in defining industry's material defect grade levels for many years. ASTM Reference Radiographs are used extensively as even the American Society for Metals Nondestructive Inspection and Quality Control Metals Handbook, Volume 11, eighth edition refers to ASTM Standard Reference Radiographs. The recently published E 1648 Standard Reference Radiographs for Examination of Aluminum Fusion Welds is a prime example of the on-going need for these references. To date, 14 Standard Reference Radiographs have been published to characterize material defects. Standard Reference Radiographs do not adequately address film-less radiologic methods. There are differences in mediums to content with. On a computer CRT defect indications appear differently when compared to indications viewed in a radiograph on a view box. Industry that uses non-film radiologic methods of inspection can be burdened with additional time and money developing internal standard reference radiologic images. These references may be deemed necessary for grading levels of product defects. Because there are no ASTM Standard Reference Radiologic data files for addressing this need in the industry, the authors of this paper suggested implementing a method for their creation under ASTM supervision. ASTM can assure continuity to those users making the transition from analog radiographic images to digital image data by swiftly addressing the requirements for reference digital image standards. The current status and possible future activities regarding a method to create digital data files is presented in this paper summary

A Comparative Study on Diagnostic Accuracy of Colour Coded Digital Images, Direct Digital Images and Conventional Radiographs for Periapical Lesions – An In Vitro Study

Science.gov (United States)

Mubeen; K.R., Vijayalakshmi; Bhuyan, Sanat Kumar; Panigrahi, Rajat G; Priyadarshini, Smita R; Misra, Satyaranjan; Singh, Chandravir

2014-01-01

Objectives: The identification and radiographic interpretation of periapical bone lesions is important for accurate diagnosis and treatment. The present study was undertaken to study the feasibility and diagnostic accuracy of colour coded digital radiographs in terms of presence and size of lesion and to compare the diagnostic accuracy of colour coded digital images with direct digital images and conventional radiographs for assessing periapical lesions. Materials and Methods: Sixty human dry cadaver hemimandibles were obtained and periapical lesions were created in first and second premolar teeth at the junction of cancellous and cortical bone using a micromotor handpiece and carbide burs of sizes 2, 4 and 6. After each successive use of round burs, a conventional, RVG and colour coded image was taken for each specimen. All the images were evaluated by three observers. The diagnostic accuracy for each bur and image mode was calculated statistically. Results: Our results showed good interobserver (kappa > 0.61) agreement for the different radiographic techniques and for the different bur sizes. Conventional Radiography outperformed Digital Radiography in diagnosing periapical lesions made with Size two bur. Both were equally diagnostic for lesions made with larger bur sizes. Colour coding method was least accurate among all the techniques. Conclusion: Conventional radiography traditionally forms the backbone in the diagnosis, treatment planning and follow-up of periapical lesions. Direct digital imaging is an efficient technique, in diagnostic sense. Colour coding of digital radiography was feasible but less accurate however, this imaging technique, like any other, needs to be studied continuously with the emphasis on safety of patients and diagnostic quality of images. PMID:25584318

Comparison of the automated evaluation of phantom mama in digital and digitalized images

International Nuclear Information System (INIS)

Santana, Priscila do Carmo

2011-01-01

Mammography is an essential tool for diagnosis and early detection of breast cancer if it is provided as a very good quality service. The process of evaluating the quality of radiographic images in general, and mammography in particular, can be much more accurate, practical and fast with the help of computer analysis tools. This work compare the automated methodology for the evaluation of scanned digital images the phantom mama. By applied the DIP method techniques was possible determine geometrical and radiometric images evaluated. The evaluated parameters include circular details of low contrast, contrast ratio, spatial resolution, tumor masses, optical density and background in Phantom Mama scanned and digitized images. The both results of images were evaluated. Through this comparison was possible to demonstrate that this automated methodology is presented as a promising alternative for the reduction or elimination of subjectivity in both types of images, but the Phantom Mama present insufficient parameters for spatial resolution evaluation. (author)

Topology-Preserving Rigid Transformation of 2D Digital Images.

Science.gov (United States)

Ngo, Phuc; Passat, Nicolas; Kenmochi, Yukiko; Talbot, Hugues

2014-02-01

We provide conditions under which 2D digital images preserve their topological properties under rigid transformations. We consider the two most common digital topology models, namely dual adjacency and well-composedness. This paper leads to the proposal of optimal preprocessing strategies that ensure the topological invariance of images under arbitrary rigid transformations. These results and methods are proved to be valid for various kinds of images (binary, gray-level, label), thus providing generic and efficient tools, which can be used in particular in the context of image registration and warping.

Digital imaging of autoradiographs from paintings by Georges de La Tour (1593-1652)

CERN Document Server

Fischer, C O; Laurenze, C; Schmidt, C; Slusallek, K

1999-01-01

The artistic work of the painter Georges de La Tour has been studied very intensively in the last few years, mainly by French and US-American art historians and natural scientists. To support the in-depth analysis of two paintings from the Kimbell Art Museum in Fort Worth, Texas, USA, two similar paintings from the Gemaeldegalerie Berlin have been investigated. The method of neutron activation autoradiography has been applied using imaging plates with digital image processing.

Digital image technology and a measurement tool in physical models

CSIR Research Space (South Africa)

Phelp, David

2006-05-01

Full Text Available Advances in digital image technology has allowed us to use accurate, but relatively cost effective technology to measure a number of varied activities in physical models. The capturing and manipulation of high resolution digital images can be used...

The establishment of Digital Image Capture System(DICS) using conventional simulator

International Nuclear Information System (INIS)

Oh, Tae Sung; Park, Jong Il; Byun, Young Sik; Shin, Hyun Kyoh

2004-01-01

The simulator is used to determine patient field and ensure the treatment field, which encompasses the required anatomy during patient normal movement such as during breathing. The latest simulator provide real time display of still, fluoroscopic and digitalized image, but conventional simulator is not yet. The purpose of this study is to introduce digital image capture system(DICS) using conventional simulator and clinical case using digital captured still and fluoroscopic image. We connect the video signal cable to the video terminal in the back up of simulator monitor, and connect the video jack to the A/D converter. After connection between the converter jack and computer, We can acquire still image and record fluoroscopic image with operating image capture program. The data created with this system can be used in patient treatment, and modified for verification by using image processing software. (j.e. photoshop, paintshop) DICS was able to establish easy and economical procedure. DCIS image was helpful for simulation. DICS imaging was powerful tool in the evaluation of the department specific patient positioning. Because the commercialized simulator based of digital capture is very expensive, it is not easily to establish DICS simulator in the most hospital. DICS using conventional simulator enable to utilize the practical use of image equal to high cost digitalized simulator and to research many clinical cases in case of using other software program.

A radiographic image archive system on digital optical disks

International Nuclear Information System (INIS)

Mankovich, N.J.; Taira, R.K.; Cho, P.S.; Wong, W.K.; Stewart, B.K.; Huang, H.K.

1986-01-01

The recent introduction of projection computed radiography (CR) systems allows radiology departments to consider digital operation in over 90% of performed procedures. Ideally, current patient procedures from CT, CT, and MR along with laser-digitized historical films should be centrally stored at their full digital resolution. Magnetic disks, because of their limited storage capacity and expense, can only retain these data on a limited basis. The author devised an optical disk archive system which automatically stores images directly onto 2.6-gigabyte optical cartridges without recourse to film. This system is in full clinical operation in the UCLA Pediatric Radiology Section of the authors' department. From this experience they present (a) an analysis of the digital archiving requirements of the Pediatric Radiology Section based on CR, CT, MR, and laser digitized films; (b) the archive and retrieval methods along with performance statistics; and (c) the procedure for assuring digital image integrity

Image quality in digital radiographic systems

Directory of Open Access Journals (Sweden)

Almeida Solange Maria de

2003-01-01

Full Text Available The aim of the present study was to evaluate the image quality of four direct digital radiographic systems. Radiographs were made of the maxillary central incisor and mandibular left molar regions of a dry skull, and an aluminum step-wedge. The X-ray generator operated at 10 mA, 60 and 70 kVp, and images were acquired with 3, 5, 8, 12, 24 and 48 exposure pulses. Six well-trained observers classified the images by means of scores from 1 to 3. Collected data were submitted to nonparametric statistical analysis using Fisher's exact test. Statistical analysis showed significant differences (p<0.01 in image quality with the four systems. Based on the results, it was possible to conclude that: 1 all of the digital systems presented good performance in producing acceptable images for diagnosis, if the exposures of the step-wedge and the maxillary central incisor region were made at 5 pulses, as well as at 8 pulses for the mandibular left molar region, selecting 60 or 70kVp; 2 higher percentages of acceptable images were obtained with the administration of lower radiation doses in CCD-sensors (charge-coupled device; 3 the Storage Phosphor systems produced acceptable images at a large range of exposure settings, that included low, intermediate and high radiation doses.

Mechanical shape correlation : a novel integrated digital image correlation approach

NARCIS (Netherlands)

Kleinendorst, S.M.; Hoefnagels, J.P.M.; Geers, M.G.D.; Lamberti, L.; Lin, M.-T.; Furlong, C.; Sciammarella, C.

2018-01-01

Mechanical Shape Correlation (MSC) is a novel integrated digital image correlation technique, used to determine the optimal set of constitutive parameters to describe the experimentally observed mechanical behavior of a test specimen, based on digital images taken during the experiment. In contrast

Global manipulation of digital images can lead to variation in cytological diagnosis.

Science.gov (United States)

Prasad, H; Wanjari, Sangeeta; Parwani, Rajkumar

2011-03-31

With the adoption of a completely electronic workflow by several journals and the advent of telepathology, digital imaging has become an integral part of every scientific research. However, manipulating digital images is very easy, and it can lead to misinterpretations. To analyse the impact of manipulating digital images on their diagnosis. Digital images were obtained from Papanicolaou-stained smears of dysplastic and normal oral epithelium. They were manipulated using GNU Image Manipulation Program (GIMP) to alter their brightness and contrast and color levels. A Power Point presentation composed of slides of these manipulated images along with the unaltered originals arranged randomly was created. The presentation was shown to five observers individually who rated the images as normal, mild, moderate or severe dysplasia. Weighted κ statistics was used to measure and assess the levels of agreement between observers. Levels of agreement between manipulated images and original images varied greatly among observers. Variation in diagnosis was in the form of overdiagnosis or under-diagnosis, usually by one grade. Global manipulations of digital images of cytological slides can significantly affect their interpretation. Such manipulations should therefore be kept to a minimum, and avoided wherever possible.

Exploratory survey of image quality on CR digital mammography imaging systems in Mexico

International Nuclear Information System (INIS)

Gaona, E.; Rivera, T.; Arreola, M.; Franco, J.; Molina, N.; Alvarez, B.; Azorín, C.G.; Casian, G.

2014-01-01

The purpose of this study was to assess the current status of image quality and dose in computed radiographic digital mammography (CRDM) systems. Studies included CRDM systems of various models and manufacturers which dose and image quality comparisons were performed. Due to the recent rise in the use of digital radiographic systems in Mexico, CRDM systems are rapidly replacing conventional film-screen systems without any regard to quality control or image quality standards. Study was conducted in 65 mammography facilities which use CRDM systems in the Mexico City and surrounding States. The systems were tested as used clinically. This means that the dose and beam qualities were selected using the automatic beam selection and photo-timed features. All systems surveyed generate laser film hardcopies for the radiologist to read on a scope or mammographic high luminance light box. It was found that 51 of CRDM systems presented a variety of image artefacts and non-uniformities arising from inadequate acquisition and processing, as well as from the laser printer itself. Undisciplined alteration of image processing settings by the technologist was found to be a serious prevalent problem in 42 facilities. Only four of them showed an image QC program which is periodically monitored by a medical physicist. The Average Glandular Dose (AGD) in the surveyed systems was estimated to have a mean value of 2.4 mGy. To improve image quality in mammography and make more efficient screening mammographic in early detection of breast cancer is required new legislation. - Highlights: • Radiation dose in CR digital mammography (CRDM) systems was determined. • Image quality related with dose in CR digital mammography (CRDM) systems was analysed. • Image processing artefacts were observed and correlated with dose. • Measured entrance dose by TL phosphors could be good parameter for radiation protection optimization in patient

Digital implementation of a neural network for imaging

Science.gov (United States)

Wood, Richard; McGlashan, Alex; Yatulis, Jay; Mascher, Peter; Bruce, Ian

2012-10-01

This paper outlines the design and testing of a digital imaging system that utilizes an artificial neural network with unsupervised and supervised learning to convert streaming input (real time) image space into parameter space. The primary objective of this work is to investigate the effectiveness of using a neural network to significantly reduce the information density of streaming images so that objects can be readily identified by a limited set of primary parameters and act as an enhanced human machine interface (HMI). Many applications are envisioned including use in biomedical imaging, anomaly detection and as an assistive device for the visually impaired. A digital circuit was designed and tested using a Field Programmable Gate Array (FPGA) and an off the shelf digital camera. Our results indicate that the networks can be readily trained when subject to limited sets of objects such as the alphabet. We can also separate limited object sets with rotational and positional invariance. The results also show that limited visual fields form with only local connectivity.

A review on the application of medical infrared thermal imaging in hands

Science.gov (United States)

Sousa, Elsa; Vardasca, Ricardo; Teixeira, Sérgio; Seixas, Adérito; Mendes, Joaquim; Costa-Ferreira, António

2017-09-01

Infrared Thermal (IRT) imaging is a medical imaging modality to study skin temperature in real time, providing physiological information about the underlining structures. One of the most accessible body sites to be investigated using such imaging method is the hands, which can reflect valuable information about conditions affecting the upper limbs. The aim of this review is to acquaint the successful applications of IRT in the hands with a medical scope, opening horizons for future applications based in the achieved results. A systematic literature review was performed in order to assess in which applications medical IRT imaging was applied to the hands. The literature search was conducted in the reference databases: PubMed, Scopus and ISI Web of Science, making use of keywords (hand, thermography, infrared imaging, thermal imaging) combination that were present at the title and abstract. No temporal restriction was made. As a result, 4260 articles were identified, after removal of duplicates, 3224 articles remained and from first title and abstract filtering, a total of 388 articles were considered. After application of exclusion criteria (non-availability, non-clinical applications, reviews, case studies, written in other languages than English and using liquid crystal thermography), 146 articles were considered for this review. It can be verified that thermography provides useful diagnostic and monitoring information of conditions that directly or indirectly related to hands, as well as aiding in the treatment assessment. Trends and future challenges for IRT applications on hands are provided to stimulate researchers and clinicians to explore and address them.

Digital Correlation based on Wavelet Transform for Image Detection

International Nuclear Information System (INIS)

Barba, L; Vargas, L; Torres, C; Mattos, L

2011-01-01

In this work is presented a method for the optimization of digital correlators to improve the characteristic detection on images using wavelet transform as well as subband filtering. It is proposed an approach of wavelet-based image contrast enhancement in order to increase the performance of digital correlators. The multiresolution representation is employed to improve the high frequency content of images taken into account the input contrast measured for the original image. The energy of correlation peaks and discrimination level of several objects are improved with this technique. To demonstrate the potentiality in extracting characteristics using the wavelet transform, small objects inside reference images are detected successfully.

Digital image processing in art conservation

Czech Academy of Sciences Publication Activity Database

Zitová, Barbara; Flusser, Jan

č. 53 (2003), s. 44-45 ISSN 0926-4981 Institutional research plan: CEZ:AV0Z1075907 Keywords : art conservation * digital image processing * change detection Subject RIV: JD - Computer Applications, Robotics

Digital pulse processor for ion beam microprobe imaging

International Nuclear Information System (INIS)

Bogovac, M.; Jaksic, M.; Wegrzynek, D.; Markowicz, A.

2009-01-01

Capabilities of spectroscopic ion beam analysis (IBA) techniques that are available in ion microprobe facilities can be greatly improved by the use of digital pulse processing. We report here development of a digital multi parameter data acquisition system suitable for IBA imaging applications. Input signals from charge sensitive preamplifier are conditioned by using a simple circuit and digitized with fast ADCs. The digitally converted signals are processed in real time using FPGA. Implementation of several components of the system is presented.

The comparison between SVD-DCT and SVD-DWT digital image watermarking

Science.gov (United States)

Wira Handito, Kurniawan; Fauzi, Zulfikar; Aminy Ma’ruf, Firda; Widyaningrum, Tanti; Muslim Lhaksmana, Kemas

2018-03-01

With internet, anyone can publish their creation into digital data simply, inexpensively, and absolutely easy to be accessed by everyone. However, the problem appears when anyone else claims that the creation is their property or modifies some part of that creation. It causes necessary protection of copyrights; one of the examples is with watermarking method in digital image. The application of watermarking technique on digital data, especially on image, enables total invisibility if inserted in carrier image. Carrier image will not undergo any decrease of quality and also the inserted image will not be affected by attack. In this paper, watermarking will be implemented on digital image using Singular Value Decomposition based on Discrete Wavelet Transform (DWT) and Discrete Cosine Transform (DCT) by expectation in good performance of watermarking result. In this case, trade-off happen between invisibility and robustness of image watermarking. In embedding process, image watermarking has a good quality for scaling factor < 0.1. The quality of image watermarking in decomposition level 3 is better than level 2 and level 1. Embedding watermark in low-frequency is robust to Gaussian blur attack, rescale, and JPEG compression, but in high-frequency is robust to Gaussian noise.

Effects of image enhancement on reliability of landmark identification in digital cephalometry

Directory of Open Access Journals (Sweden)

M Oshagh

2013-01-01

Full Text Available Introduction: Although digital cephalometric radiography is gaining popularity in orthodontic practice, the most important source of error in its tracing is uncertainty in landmark identification. Therefore, efforts to improve accuracy in landmark identification were directed primarily toward the improvement in image quality. One of the more useful techniques of this process involves digital image enhancement which can increase overall visual quality of image, but this does not necessarily mean a better identification of landmarks. The purpose of this study was to evaluate the effectiveness of digital image enhancements on reliability of landmark identification. Materials and Methods: Fifteen common landmarks including 10 skeletal and 5 soft tissues were selected on the cephalograms of 20 randomly selected patients, prepared in Natural Head Position (NHP. Two observers (orthodontists identified landmarks on the 20 original photostimulable phosphor (PSP digital cephalogram images and 20 enhanced digital images twice with an intervening time interval of at least 4 weeks. The x and y coordinates were further analyzed to evaluate the pattern of recording differences in horizontal and vertical directions. Reliability of landmarks identification was analyzed by paired t test. Results: There was a significant difference between original and enhanced digital images in terms of reliability of points Ar and N in vertical and horizontal dimensions, and enhanced images were significantly more reliable than original images. Identification of A point, Pogonion and Pronasal points, in vertical dimension of enhanced images was significantly more reliable than original ones. Reliability of Menton point identification in horizontal dimension was significantly more in enhanced images than original ones. Conclusion: Direct digital image enhancement by altering brightness and contrast can increase reliability of some landmark identification and this may lead to more

Teaching and Learning to Read Images and Movies in the Digital Age

Directory of Open Access Journals (Sweden)

Michaël Bourgatte

2015-10-01

Full Text Available With digital technologies and Internet, pictures, movies and videos are increasingly present in our daily lives. Images are an excellent way to be informed, to communicate and, obviously, to learn. This phenomenon questions the educational stakeholders (public authorities, teachers, researchers, etc. who are seeking solutions to better train and support learners to understand the meaning of images and to be able to analyze them. In this context, we have set up educational activities with a film analysis software to promote the discovery of cinema. Two questions were asked at the beginning of the project. The first one relates to building competencies about film language with the help of digital technologies. The second question relates to the effects produced by the use of this very software in the classroom. To answer these questions, one must refer Gregory Bateson’s notion of double bind.

Global manipulation of digital images can lead to variation in cytological diagnosis

Directory of Open Access Journals (Sweden)

H Prasad

2011-01-01

Full Text Available Background: With the adoption of a completely electronic workflow by several journals and the advent of telepathology, digital imaging has become an integral part of every scientific research. However, manipulating digital images is very easy, and it can lead to misinterpretations. Aim: To analyse the impact of manipulating digital images on their diagnosis. Design: Digital images were obtained from Papanicolaou-stained smears of dysplastic and normal oral epithelium. They were manipulated using GNU Image Manipulation Program (GIMP to alter their brightness and contrast and color levels. A Power Point presentation composed of slides of these manipulated images along with the unaltered originals arranged randomly was created. The presentation was shown to five observers individually who rated the images as normal, mild, moderate or severe dysplasia. Weighted k statistics was used to measure and assess the levels of agreement between observers. Results: Levels of agreement between manipulated images and original images varied greatly among observers. Variation in diagnosis was in the form of overdiagnosis or under-diagnosis, usually by one grade. Conclusion: Global manipulations of digital images of cytological slides can significantly affect their interpretation. Such manipulations should therefore be kept to a minimum, and avoided wherever possible.

Touch-less interaction with medical images using hand & foot gestures

DEFF Research Database (Denmark)

Jalaliniya, Shahram; Smith, Jeremiah; Sousa, Miguel

2013-01-01

control. In this paper, we present a system for gesture-based interaction with medical images based on a single wristband sensor and capacitive floor sensors, allowing for hand and foot gesture input. The first limited evaluation of the system showed an acceptable level of accuracy for 12 different hand...... & foot gestures; also users found that our combined hand and foot based gestures are intuitive for providing input....

Low-Light Image Enhancement Using Adaptive Digital Pixel Binning

Directory of Open Access Journals (Sweden)

Yoonjong Yoo

2015-06-01

Full Text Available This paper presents an image enhancement algorithm for low-light scenes in an environment with insufficient illumination. Simple amplification of intensity exhibits various undesired artifacts: noise amplification, intensity saturation, and loss of resolution. In order to enhance low-light images without undesired artifacts, a novel digital binning algorithm is proposed that considers brightness, context, noise level, and anti-saturation of a local region in the image. The proposed algorithm does not require any modification of the image sensor or additional frame-memory; it needs only two line-memories in the image signal processor (ISP. Since the proposed algorithm does not use an iterative computation, it can be easily embedded in an existing digital camera ISP pipeline containing a high-resolution image sensor.

Are digital images good enough? A comparative study of conventional film-screen vs digital radiographs on printed images of total hip replacement

International Nuclear Information System (INIS)

Eklund, K.; Jonsson, K.; Lindblom, G.; Lundin, B.; Sanfridsson, J.; Sloth, M.; Sivberg, B.

2004-01-01

The aim of this study was to evaluate the inter- and intra-observer variability and to find differences in diagnostic safety between digital and analog technique in diagnostic zones around hip prostheses. In 80 patients who had had a total hip replacement (THR) for more than 2 years, a conventional image and a digital image were taken. Gruen's model of seven distinct regions of interest was used for evaluations. Five experienced radiologists observed the seven regions and noted in a protocol the following distances: stem-cement; cement-bone; and stem-bone. All images were printed on hard copies and were read twice. Weighted kappa, κ w , analyses were used. The two most frequently loosening regions, stem-cement region 1 and cement-bone region 7, were closely analyzed. In region 1 the five observers had an agreement of 86.75-97.92% between analog and digital images in stem-cement, which is a varied κ w 0.29-0.71. For cement-bone region 7 an agreement of 87.21-90.45% was found, which is a varied κ w of 0.48-0.58. All the kappa values differ significantly from nil. The result shows that digital technique is as good as analog radiographs for diagnosing possible loosening of hip prostheses. (orig.)

Hand preference and magnetic resonance imaging asymmetries of the central sulcus.

Science.gov (United States)

Foundas, A L; Hong, K; Leonard, C M; Heilman, K M

1998-04-01

Hand preference is perhaps the most evident behavioral asymmetry observed in humans. Anatomic brain asymmetries that may be associated with hand preference have not been extensively studied, and no clear relationship between asymmetries of the motor system and hand preference have been established. Therefore, using volumetric magnetic resonance imaging methodologies, the surface area of the hand representation was measured along the length of the central sulcus in 15 consistent right- and 15 left-handers matched for age and gender. There was a significant leftward asymmetry of the motor hand area of the precentral gyrus in the right-handers, but no directional asymmetry was found in the left-handers. When asymmetry quotients were computed to determine the distribution of interhemispheric asymmetries, the left motor bank was greater than the right motor bank in 9 of 15 right-handers, the right motor bank was greater than the left motor bank in 3 of 15 right-handers, and the motor banks were equal in 3 of 15 right-handers. In contrast, among left-handers, the left motor bank was greater than the right motor bank in 5 of 15, the right motor bank was greater than the left motor bank in 5 of 15, and the motor banks were equal in 5 of 15. Although no direct measure of motor dexterity and skill was performed, these data suggest that anatomic asymmetries of the motor hand area may be related to hand preference because of the differences in right-handers and left-handers. Furthermore, the predominant leftward asymmetry in right-handers and the random distribution of asymmetries in the left-handers support Annett's right-shift theory. It is unclear, however, whether these asymmetries are the result of preferential hand use or are a reflection of a biologic preference to use one limb over the other.

Perceptual digital imaging methods and applications

CERN Document Server

Lukac, Rastislav

2012-01-01

Visual perception is a complex process requiring interaction between the receptors in the eye that sense the stimulus and the neural system and the brain that are responsible for communicating and interpreting the sensed visual information. This process involves several physical, neural, and cognitive phenomena whose understanding is essential to design effective and computationally efficient imaging solutions. Building on advances in computer vision, image and video processing, neuroscience, and information engineering, perceptual digital imaging greatly enhances the capabilities of tradition

Digital image processing an algorithmic approach with Matlab

CERN Document Server

Qidwai, Uvais

2009-01-01

Introduction to Image Processing and the MATLAB EnvironmentIntroduction Digital Image Definitions: Theoretical Account Image Properties MATLAB Algorithmic Account MATLAB CodeImage Acquisition, Types, and File I/OImage Acquisition Image Types and File I/O Basics of Color Images Other Color Spaces Algorithmic Account MATLAB CodeImage ArithmeticIntroduction Operator Basics Theoretical TreatmentAlgorithmic Treatment Coding ExamplesAffine and Logical Operations, Distortions, and Noise in ImagesIntroduction Affine Operations Logical Operators Noise in Images Distortions in ImagesAlgorithmic Account

Enhanced MR imaging of tenosynovitis of hand and wrist in inflammatory arthritis

Energy Technology Data Exchange (ETDEWEB)

Tehranzadeh, J.; Ashilyan, O.; Anavim, A.; Tramma, S. [Univ. of California, Orange (United States). Dept. of Radiological Sciences

2006-11-15

The purpose of this study is to describe the appearance of tenosynovitis in various tendon groups in the wrist and hand and to compare MR enhanced and non-enhanced imaging evaluation of tenosynovitis of hand and wrist in inflammatory arthritis. We reviewed 72 MRI studies of hands and wrists, including coronal, axial and sagittal images in 30 consecutive patients with inflammatory arthritis and tenosynovitis. We compared the degree of synovitis on T2-weighted vs contrast-enhanced T1-weighted images, using a predetermined scale. We also measured the extent of tenosynovitis in three dimensions. The tendons were assigned to volar, dorsal, ulnar and radial groups in the wrist and to extensor, flexor and thumb groups in the hand. Degree of tenosynovitis (graded 0-3), cross-sectional area and volume of the inflamed synovium in various tendon groups were then compared by statistical analysis. Review of the medical records revealed the following diagnoses in our patient population: rheumatoid arthritis (n=16), unspecified inflammatory polyarthritis (n=9), psoriatic arthritis (n=2), CREST syndrome (n=1), systemic lupus erythematosus (n=1), paraneoplastic syndrome with arthritis (n=1). The average T2 brightness scores and post-gadolinium enhancement scores were 1.0 and 1.7 respectively (P<0.001) in the wrist studies. The average T2 brightness scores and post-gadolinium enhancement scores were 0.7 and 1.4, respectively (P<0.001) in the hand studies. The average sensitivity of T2-weighted imaging for detection of tenosynovitis was 40% in the hand and 67% in the wrist tendons, when contrast-enhanced images were used as a reference. Carpal tunnel flexor tendons were the most frequently affected tendons of the wrist. The most frequently affected tendons of the hand were second and third flexor tendons. The hand flexors demonstrated higher degrees of enhancement and larger volumes of the inflamed tenosynovium than did the hand extensors and tendons of the thumb.

Enhanced MR imaging of tenosynovitis of hand and wrist in inflammatory arthritis

International Nuclear Information System (INIS)

Tehranzadeh, J.; Ashilyan, O.; Anavim, A.; Tramma, S.

2006-01-01

The purpose of this study is to describe the appearance of tenosynovitis in various tendon groups in the wrist and hand and to compare MR enhanced and non-enhanced imaging evaluation of tenosynovitis of hand and wrist in inflammatory arthritis. We reviewed 72 MRI studies of hands and wrists, including coronal, axial and sagittal images in 30 consecutive patients with inflammatory arthritis and tenosynovitis. We compared the degree of synovitis on T2-weighted vs contrast-enhanced T1-weighted images, using a predetermined scale. We also measured the extent of tenosynovitis in three dimensions. The tendons were assigned to volar, dorsal, ulnar and radial groups in the wrist and to extensor, flexor and thumb groups in the hand. Degree of tenosynovitis (graded 0-3), cross-sectional area and volume of the inflamed synovium in various tendon groups were then compared by statistical analysis. Review of the medical records revealed the following diagnoses in our patient population: rheumatoid arthritis (n=16), unspecified inflammatory polyarthritis (n=9), psoriatic arthritis (n=2), CREST syndrome (n=1), systemic lupus erythematosus (n=1), paraneoplastic syndrome with arthritis (n=1). The average T2 brightness scores and post-gadolinium enhancement scores were 1.0 and 1.7 respectively (P<0.001) in the wrist studies. The average T2 brightness scores and post-gadolinium enhancement scores were 0.7 and 1.4, respectively (P<0.001) in the hand studies. The average sensitivity of T2-weighted imaging for detection of tenosynovitis was 40% in the hand and 67% in the wrist tendons, when contrast-enhanced images were used as a reference. Carpal tunnel flexor tendons were the most frequently affected tendons of the wrist. The most frequently affected tendons of the hand were second and third flexor tendons. The hand flexors demonstrated higher degrees of enhancement and larger volumes of the inflamed tenosynovium than did the hand extensors and tendons of the thumb

Hands on, mobiles on The use of a digital narrative as a scaffolding remedy in a classical science centre

Directory of Open Access Journals (Sweden)

Anne Kahr-Højland

2010-12-01

Full Text Available This article examines an educational design experiment which aimed to support young people’s involvement and reflection in the exhibition at a Danish science centre. The experiment consisted in the examination of the design and implementation of a mobile phone facilitated narrative, which was planned as a so-called scaffolding remedy in the hands-on based exhibition. The digital narrative, called EGO-TRAP, was developed using Design-Based Research as the overall methodological framework. The study of students’ interactions in the exhibition suggests, among other things, that because of its quality as a digital narrative, EGO-TRAP scaffolds pleasurable engagement and counteracts the tendency of "random button pressing" that often occurs in classical science centre exhibitions. In this connection, the mobile phone plays an essential role due to the fact that it, as the favoured media by the young students, offers an experience which they describe as both personal and flexible.

Robotic Hand

Science.gov (United States)

1993-01-01

The Omni-Hand was developed by Ross-Hime Designs, Inc. for Marshall Space Flight Center (MSFC) under a Small Business Innovation Research (SBIR) contract. The multiple digit hand has an opposable thumb and a flexible wrist. Electric muscles called Minnacs power wrist joints and the interchangeable digits. Two hands have been delivered to NASA for evaluation for potential use on space missions and the unit is commercially available for applications like hazardous materials handling and manufacturing automation. Previous SBIR contracts resulted in the Omni-Wrist and Omni-Wrist II robotic systems, which are commercially available for spray painting, sealing, ultrasonic testing, as well as other uses.

Estimation of global daily irradiation in complex topography zones using digital elevation models and meteosat images: Comparison of the results

International Nuclear Information System (INIS)

Martinez-Durban, M.; Zarzalejo, L.F.; Bosch, J.L.; Rosiek, S.; Polo, J.; Batlles, F.J.

2009-01-01

The knowledge of the solar irradiation in a certain place is fundamental for the suitable location of solar systems, both thermal and photovoltaic. On the local scale, the topography is the most important modulating factor of the solar irradiation on the surface. In this work the global daily irradiation is estimated concerning various sky conditions, in zones of complex topography. In order to estimate the global daily irradiation we use a methodology based on a Digital Terrain Model (DTM), on one hand making use of pyranometer measurements and on the other hand utilizing satellite images. We underline that DTM application employing pyranometer measurements produces better results than estimation using satellite images, though accuracy of the same order is obtained in both cases for Root Mean Square Error (RMSE) and Mean Bias Error (MBE).

Estimation of global daily irradiation in complex topography zones using digital elevation models and meteosat images: Comparison of the results

Energy Technology Data Exchange (ETDEWEB)

Martinez-Durban, M. [Dpto. de Lenguajes y Computacion, Universidad de Almeria, 04120 Almeria (Spain); Zarzalejo, L.F.; Polo, J. [Dpto. de Energia, CIEMAT, 28040 Madrid (Spain); Bosch, J.L.; Rosiek, S.; Batlles, F.J. [Dpto. Fisica Aplicada, Universidad de Almeria, 04120 Almeria (Spain)

2009-09-15

The knowledge of the solar irradiation in a certain place is fundamental for the suitable location of solar systems, both thermal and photovoltaic. On the local scale, the topography is the most important modulating factor of the solar irradiation on the surface. In this work the global daily irradiation is estimated concerning various sky conditions, in zones of complex topography. In order to estimate the global daily irradiation we use a methodology based on a Digital Terrain Model (DTM), on one hand making use of pyranometer measurements and on the other hand utilizing satellite images. We underline that DTM application employing pyranometer measurements produces better results than estimation using satellite images, though accuracy of the same order is obtained in both cases for Root Mean Square Error (RMSE) and Mean Bias Error (MBE). (author)

Talbot phase-contrast x-ray imaging for the small joints of the hand

Energy Technology Data Exchange (ETDEWEB)

Stutman, Dan [Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218 (United States); Beck, Thomas J [Quantum Medical Metrics, 1450 South Rolling Road, Baltimore, MD 21227 (United States); Carrino, John A [Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University, Baltimore, MD 21287 (United States); Bingham, Clifton O, E-mail: stutman@pha.jhu.edu [Divisions of Rheumatology and Allergy and Clinical Immunology, Johns Hopkins University, Baltimore, MD 21224 (United States)

2011-09-07

A high-resolution radiographic method for soft tissues in the small joints of the hand would aid in the study and treatment of rheumatoid arthritis (RA) and osteoarthritis (OA), which often attacks these joints. Of particular interest would be imaging with <100 {mu}m resolution the joint cartilage, whose integrity is a main indicator of disease. Differential phase-contrast (DPC) or refraction-based x-ray imaging with Talbot grating interferometers could provide such a method, since it enhances soft tissue contrast and can be implemented with conventional x-ray tubes. A numerical joint phantom was first developed to assess the angular sensitivity and spectrum needed for a hand DPC system. The model predicts that, due to quite similar refraction indexes for joint soft tissues, the refraction effects are very small, requiring high angular resolution. To compare our model to experiment we built a high-resolution bench-top interferometer using 10 {mu}m period gratings, a W anode tube and a CCD-based detector. Imaging experiments on animal cartilage and on a human finger support the model predictions. For instance, the estimated difference between the index of refraction of cartilage and water is of only several percent at {approx}25 keV mean energy, comparable to that between the linear attenuation coefficients. The potential advantage of DPC imaging thus comes mainly from the edge enhancement at the soft tissue interfaces. Experiments using a cadaveric human finger are also qualitatively consistent with the joint model, showing that refraction contrast is dominated by tendon embedded in muscle, with the cartilage layer difficult to observe in our conditions. Nevertheless, the model predicts that a DPC radiographic system for the small hand joints of the hand could be feasible using a low energy quasi-monochromatic source, such as a K-edge filtered Rh or Mo tube, in conjunction with a {approx}2 m long 'symmetric' interferometer operated in a high Talbot order.

COMPARISON OF DIGITAL IMAGE STEGANOGRAPHY METHODS

Directory of Open Access Journals (Sweden)

S. A. Seyyedi

2013-01-01

Full Text Available Steganography is a method of hiding information in other information of different format (container. There are many steganography techniques with various types of container. In the Internet, digital images are the most popular and frequently used containers. We consider main image steganography techniques and their advantages and disadvantages. We also identify the requirements of a good steganography algorithm and compare various such algorithms.

Use of digital images to estimate soil moisture

Directory of Open Access Journals (Sweden)

João F. C. dos Santos

Full Text Available ABSTRACT The objective of this study was to analyze the relation between the moisture and the spectral response of the soil to generate prediction models. Samples with different moisture contents were prepared and photographed. The photographs were taken under homogeneous light condition and with previous correction for the white balance of the digital photograph camera. The images were processed for extraction of the median values in the Red, Green and Blue bands of the RGB color space; Hue, Saturation and Value of the HSV color space; and values of the digital numbers of a panchromatic image obtained from the RGB bands. The moisture of the samples was determined with the thermogravimetric method. Regression models were evaluated for each image type: RGB, HSV and panchromatic. It was observed the darkening of the soil with the increase of moisture. For each type of soil, a model with best fit was observed and to use these models for prediction purposes, it is necessary to choose the model with best fit in advance, according to the soil characteristics. Soil moisture estimation as a function of its spectral response by digital image processing proves promising.

Image analysis of microsialograms of the mouse parotid gland using digital image processing

International Nuclear Information System (INIS)

Yoshiura, K.; Ohki, M.; Yamada, N.

1991-01-01

The authors compared two digital-image feature-extraction methods for the analysis of microsialograms of the mouse parotid gland following either overfilling, experimentally induced acute sialoadenitis or irradiation. Microsialograms were digitized using a drum-scanning microdensitometer. The grey levels were then partitioned into four bands representing soft tissue, peripheral minor, middle-sized and major ducts, and run-length and histogram analysis of the digital images performed. Serial analysis of microsialograms during progressive filling showed that both methods depicted the structural characteristics of the ducts at each grey level. However, in the experimental groups, run-length analysis showed slight changes in the peripheral duct system more clearly. This method was therefore considered more effective than histogram analysis

An instructional guide for leaf color analysis using digital imaging software

Science.gov (United States)

Paula F. Murakami; Michelle R. Turner; Abby K. van den Berg; Paul G. Schaberg

2005-01-01

Digital color analysis has become an increasingly popular and cost-effective method utilized by resource managers and scientists for evaluating foliar nutrition and health in response to environmental stresses. We developed and tested a new method of digital image analysis that uses Scion Image or NIH image public domain software to quantify leaf color. This...

Establishing imaging sensor specifications for digital still cameras

Science.gov (United States)

Kriss, Michael A.

2007-02-01

Digital Still Cameras, DSCs, have now displaced conventional still cameras in most markets. The heart of a DSC is thought to be the imaging sensor, be it Full Frame CCD, and Interline CCD, a CMOS sensor or the newer Foveon buried photodiode sensors. There is a strong tendency by consumers to consider only the number of mega-pixels in a camera and not to consider the overall performance of the imaging system, including sharpness, artifact control, noise, color reproduction, exposure latitude and dynamic range. This paper will provide a systematic method to characterize the physical requirements of an imaging sensor and supporting system components based on the desired usage. The analysis is based on two software programs that determine the "sharpness", potential for artifacts, sensor "photographic speed", dynamic range and exposure latitude based on the physical nature of the imaging optics, sensor characteristics (including size of pixels, sensor architecture, noise characteristics, surface states that cause dark current, quantum efficiency, effective MTF, and the intrinsic full well capacity in terms of electrons per square centimeter). Examples will be given for consumer, pro-consumer, and professional camera systems. Where possible, these results will be compared to imaging system currently on the market.

Digital tomosynthesis with an on-board kilovoltage imaging device

International Nuclear Information System (INIS)

Godfrey, Devon J.; Yin, F.-F.; Oldham, Mark; Yoo, Sua; Willett, Christopher

2006-01-01

Purpose: To generate on-board digital tomosynthesis (DTS) and reference DTS images for three-dimensional image-guided radiation therapy (IGRT) as an alternative to conventional portal imaging or on-board cone-beam computed tomography (CBCT). Methods and Materials: Three clinical cases (prostate, head-and-neck, and liver) were selected to illustrate the capabilities of on-board DTS for IGRT. Corresponding reference DTS images were reconstructed from digitally reconstructed radiographs computed from planning CT image sets. The effect of scan angle on DTS slice thickness was examined by computing the mutual information between coincident CBCT and DTS images, as the DTS scan angle was varied from 0 o to 165 o . A breath-hold DTS acquisition strategy was implemented to remove respiratory motion artifacts. Results: Digital tomosynthesis slices appeared similar to coincident CBCT planes and yielded substantially more anatomic information than either kilovoltage or megavoltage radiographs. Breath-hold DTS acquisition improved soft-tissue visibility by suppressing respiratory motion. Conclusions: Improved bony and soft-tissue visibility in DTS images is likely to improve target localization compared with radiographic verification techniques and might allow for daily localization of a soft-tissue target. Breath-hold DTS is a potential alternative to on-board CBCT for sites prone to respiratory motion

Comparative study of digital laser film and analog paper image recordings

International Nuclear Information System (INIS)

Lee, K.R.; Cox, G.G.; Templeton, A.W.; Preston, D.F.; Anderson, W.H.; Hensley, K.S.; Dwyer, S.J.

1987-01-01

The increase in the use of various imaging modalities demands higher quality and more efficacious analog image recordings. Laser electronic recordings with digital array prints of 4,000 x 5,000 x 12 bits obtained using laser-sensitive film or paper are being evaluated. Dry silver paper recordings are being improved and evaluated. High-resolution paper dot printers are being studied to determine their gray-scale capabilities. The authors evaluated the image quality, costs, clinical utilization, and acceptability of CT scans, MR images, digital subtraction angiograms, digital radiographs, and radionuclide scans recorded by seven different printers (three laser, three silver paper, and one dot) and compared the same features in conventional film recording. This exhibit outlines the technical developments and instrumentation of digital laser film and analog paper recorders and presents the results of the study

The application of digital image plane holography technology to identify Chinese herbal medicine

Science.gov (United States)

Wang, Huaying; Guo, Zhongjia; Liao, Wei; Zhang, Zhihui

2012-03-01

In this paper, the imaging technology of digital image plane holography to identify the Chinese herbal medicine is studied. The optical experiment system of digital image plane holography which is the special case of pre-magnification digital holography was built. In the record system, one is an object light by using plane waves which illuminates the object, and the other one is recording hologram by using spherical light wave as reference light. There is a Micro objective lens behind the object. The second phase factor which caus ed by the Micro objective lens can be eliminated by choosing the proper position of the reference point source when digital image plane holography is recorded by spherical light. In this experiment, we use the Lygodium cells and Onion cells as the object. The experiment results with Lygodium cells and Onion cells show that digital image plane holography avoid the process of finding recording distance by using auto-focusing approach, and the phase information of the object can be reconstructed more accurately. The digital image plane holography is applied to the microscopic imaging of cells more effectively, and it is suit to apply for the identify of Chinese Herbal Medicine. And it promotes the application of digital holographic in practice.

Development of the bedridden person support system using hand gesture.

Science.gov (United States)

Ichimura, Kouhei; Magatani, Kazushige

2015-08-01

The purpose of this study is to support the bedridden and physically handicapped person who live independently. In this study, we developed Electric appliances control system that can be used on the bed. The subject can control Electric appliances using hand motion. Infrared sensors of a Kinect are used for the hand motion detection. Our developed system was tested with some normal subjects and results of the experiment were evaluated. In this experiment, all subjects laid on the bed and tried to control our system. As results, most of subjects were able to control our developed system perfectly. However, motion tracking of some subject's hand was reset forcibly. It was difficult for these subjects to make the system recognize his opened hand. From these results, we think if this problem will be improved our support system will be useful for the bedridden and physically handicapped persons.

Chest imaging with dual-energy substraction digital tomosynthesis

International Nuclear Information System (INIS)

Sone, S.; Kasuga, T.; Sakai, F.; Hirano, H.; Kubo, K.; Morimoto, M.; Takemura, K.; Hosoba, M.

1993-01-01

Dual-energy subtraction digital tomosynthesis with pulsed X-ray and rapid kV switching was used to examine calcifications in pulmonary lesions. The digital tomosynthesis system used included a conventional fluororadiographic TV unit with linear tomographic capabilities, a high resolution videocamera, and an image processing unit. Low-voltage, high voltage, and soft tissue subtracted or bone subtracted tomograms of any desired layer height were reconstructed from the image data acquired during a single tomographic swing. Calcifications, as well as their characteristics and distribution in pulmonary lesions, were clearly shown. The images also permitted discrimination of calcifications from dense fibrotic lesions. This technique was effective in demonstrating calcifications together with a solitary mass or disseminated nodules. (orig.)

Clinical evaluation of digital displays for PACS work stations

International Nuclear Information System (INIS)

Highman, J.H.; Craig, J.O.M.C.; Dawood, R.M.; Todd-Pokropek, A.; Porter, A.; Glass, H.I.; Wadsworth, J.

1989-01-01

The requirements for display of radiographic images at PAVS work stations is critical if reporting at CRT terminal is to become routine practice. This study determines the accuracy of reporting for the digital images displayed on commercially available systems. A number of pathologic conditions were selected by virtue of the high demands they made on spatial and contrast resolution. They included hyperparathyroid subperiosteal resorption in the hands, pneumocystis pneumonia, and mammographic microcalcification. For each condition, a series of up to 100 films were collected; approximately half were normal controls. These were digitized at 200 μm. Original films and their digitized images displayed on a 1,280-line monitor have been reported

Metadata requirements for results of diagnostic imaging procedures: a BIIF profile to support user applications

Science.gov (United States)

Brown, Nicholas J.; Lloyd, David S.; Reynolds, Melvin I.; Plummer, David L.

2002-05-01

A visible digital image is rendered from a set of digital image data. Medical digital image data can be stored as either: (a) pre-rendered format, corresponding to a photographic print, or (b) un-rendered format, corresponding to a photographic negative. The appropriate image data storage format and associated header data (metadata) required by a user of the results of a diagnostic procedure recorded electronically depends on the task(s) to be performed. The DICOM standard provides a rich set of metadata that supports the needs of complex applications. Many end user applications, such as simple report text viewing and display of a selected image, are not so demanding and generic image formats such as JPEG are sometimes used. However, these are lacking some basic identification requirements. In this paper we make specific proposals for minimal extensions to generic image metadata of value in various domains, which enable safe use in the case of two simple healthcare end user scenarios: (a) viewing of text and a selected JPEG image activated by a hyperlink and (b) viewing of one or more JPEG images together with superimposed text and graphics annotation using a file specified by a profile of the ISO/IEC Basic Image Interchange Format (BIIF).

Problems and image processing in X-ray film digitization

International Nuclear Information System (INIS)

Kato, Syousuke; Yoshita, Hisashi; Kuranishi, Makoto; Itoh, Hajime; Mori, Kouichi; Konishi, Minoru

1992-01-01

Aiming at the realization of PACS, a study was conducted on the present state of, and various problems associated with, X-ray film digitization using a He-Ne laser-type film digitizer. Image quality was evaluated physically and clinically. With regard to the gradation specificity, the linear specificity was shown in a dynamic range of 4 figures. With regard to resolution specificity, visual evaluation was performed using a Hawlet Chart, with almost no difference being found between the CRT and laser printer output images and the decrease in resolution becoming more pronounced as the sampling pitch became greater. Clinical evaluation was performed with reference to the literature. The general evaluation of the clinicians was that although there was some deterioration for all of the shadows, (I have read this many times, but could not understand the last part.) by performing each of the kinds of image-processing enhancement of diagnostic ability was achieved, with a diagnosis being possible. The problem of unhindered diagnosis due to the development of artifacts from optical interference of the grid images projected onto the clinical pictures and digitizer sampling pitch was studied. As countermeasures, the use of a high density grid and adoption of a low-pass filter were useful in impending the development of artifacts. Regarding the operating problems, the inputting of index information requires a considerable number of manhours and a method of automatic recognition from digital data was introduced to overcome this problem. As future-prospects, the concepts of a practical system of X-ray film digitization and a film-screen system adapted to digitization were described. (author)

Problems and image processing in X-ray film digitization

Energy Technology Data Exchange (ETDEWEB)

Kato, Syousuke; Yoshita, Hisashi; Kuranishi, Makoto; Itoh, Hajime; Mori, Kouichi; Konishi, Minoru (Toyama Medical and Pharmaceutical Univ. (Japan). Hospital)

1992-11-01

Aiming at the realization of PACS, a study was conducted on the present state of, and various problems associated with, X-ray film digitization using a He-Ne laser-type film digitizer. Image quality was evaluated physically and clinically. With regard to the gradation specificity, the linear specificity was shown in a dynamic range of 4 figures. With regard to resolution specificity, visual evaluation was performed using a Hawlet Chart, with almost no difference being found between the CRT and laser printer output images and the decrease in resolution becoming more pronounced as the sampling pitch became greater. Clinical evaluation was performed with reference to the literature. The general evaluation of the clinicians was that although there was some deterioration for all of the shadows, (I have read this many times, but could not understand the last part.) by performing each of the kinds of image-processing enhancement of diagnostic ability was achieved, with a diagnosis being possible. The problem of unhindered diagnosis due to the development of artifacts from optical interference of the grid images projected onto the clinical pictures and digitizer sampling pitch was studied. As countermeasures, the use of a high density grid and adoption of a low-pass filter were useful in impending the development of artifacts. Regarding the operating problems, the inputting of index information requires a considerable number of manhours and a method of automatic recognition from digital data was introduced to overcome this problem. As future-prospects, the concepts of a practical system of X-ray film digitization and a film-screen system adapted to digitization were described. (author).

Comparison of Diagnostic Accuracy of Breast Masses Using Digitized Images Versus Screen-Film Mammography

International Nuclear Information System (INIS)

Zhigang Liang; Xiangying Du; Jiabin Liu; Xinyu Yao; Yanhui Yang; Kuncheng Li

2008-01-01

Background: Medical film digitizers play an important transitory role as digital-analogue bridges in radiology. Digitized mammograms require evaluation of performance to assure medical image quality. Purpose: To compare the diagnostic accuracy in the interpretation of breast masses using original screen-film mammograms versus digitized images. Material and Methods: A total of 72 female patients between 55 and 81 years of age suspected of having breast cancer were selected by two non-observing radiologists. Of these, 31 cases were benign lesions and 41 cases were cancer. The mammography films were digitized using a laser film digitizer. Three radiologists, each with more than 10 years of experience in mammography, interpreted the screen-film mammograms and digitized images respectively. The time interval was 4 weeks. A four-point malignancy scale was used, with 1 defined as definitely not malignant, 2 as probably not malignant, 3 as probably malignant, and 4 as definitely malignant. Receiver operating characteristic (Roc) curves, sensitivity, and specificity were compared. Results: The average area-under-the-curve (Az) value of the original screen-film mammograms was 0.921, and the average Az value of the digitized images was 0.859. This difference was not statistically significant (P=0.131). The detection specificity of extremely dense breasts was lower than that for other breast compositions for both digitized images and screen-film mammograms. No statistical significance in sensitivity and specificity was observed between digitized images and mammograms for each breast composition. Original screen-film mammograms were observed to perform better than digitized images. Conclusion: Digitized images with a spatial resolution of 175 μm can be used instead of screen-film mammograms in the diagnosis of breast cancer

New modified map for digital image encryption and its performance

Science.gov (United States)

Suryadi, MT; Yus Trinity Irsan, Maria; Satria, Yudi

2017-10-01

Protection to classified digital data becomes so important in avoiding data manipulation and alteration. The focus of this paper is in data and information protection of digital images form. Protection is provided in the form of encrypted digital image. The encryption process uses a new map, {x}n+1=\\frac{rλ {x}n}{1+λ {(1-{x}n)}2}\\quad ({mod} 1), which is called MS map. This paper will show: the results of digital image encryption using MS map and how the performance is regarding the average time needed for encryption/decryption process; randomness of key stream sequence with NIST test, histogram analysis and goodness of fit test, quality of the decrypted image by PSNR, initial value sensitivity level, and key space. The results show that the average time of the encryption process is relatively same as the decryption process and it depends to types and sizes of the image. Cipherimage (encrypted image) is uniformly distributed since: it passes the goodness of fit test and also the histogram of the cipherimage is flat; key stream, that are generated by MS map, passes frequency (monobit) test, and runs test, which means the key stream is a random sequence; the decrypted image has same quality as the original image; and initial value sensitivity reaches 10-17, and key space reaches 3.24 × 10634. So, that encryption algorithm generated by MS map is more resistant to brute-force attack and known plaintext attack.

Coordination of intrinsic and extrinsic hand muscle activity as a function of wrist joint angle during two-digit grasping.

Science.gov (United States)

Johnston, Jamie A; Bobich, Lisa R; Santello, Marco

2010-04-26

Fingertip forces result from the activation of muscles that cross the wrist and muscles whose origins and insertions reside within the hand (extrinsic and intrinsic hand muscles, respectively). Thus, tasks that involve changes in wrist angle affect the moment arm and length, hence the force-producing capabilities, of extrinsic muscles only. If a grasping task requires the exertion of constant fingertip forces, the Central Nervous System (CNS) may respond to changes in wrist angle by modulating the neural drive to extrinsic or intrinsic muscles only or by co-activating both sets of muscles. To distinguish between these scenarios, we recorded electromyographic (EMG) activity of intrinsic and extrinsic muscles of the thumb and index finger as a function of wrist angle during a two-digit object hold task. We hypothesized that changes in wrist angle would elicit EMG amplitude modulation of the extrinsic and intrinsic hand muscles. In one experimental condition we asked subjects to exert the same digit forces at each wrist angle, whereas in a second condition subjects could choose digit forces for holding the object. EMG activity was significantly modulated in both extrinsic and intrinsic muscles as a function of wrist angle (both pextrinsic and intrinsic muscles as a muscle synergy. These findings are discussed within the theoretical frameworks of synergies and common neural input across motor nuclei of hand muscles. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

Neural evidence for the use of digit-image mnemonic in a superior memorist: An fMRI study

Directory of Open Access Journals (Sweden)

Li-Jun eYin

2015-03-01

Full Text Available Some superior memorists demonstrated exceptional memory for reciting a large body of information. The underlying neural correlates, however, are seldom addressed. C.L., the current holder of Guinness World Record for reciting 67,890 digits in π, participated in this functional magnetic resonance imaging (fMRI study. Thirteen participants without any mnemonics training were included as controls. Our previous studies suggested that C.L. used a digit-image mnemonic in studying and recalling lists of digits, namely associating 2-digit groups of ‘00’ to ‘99’ with images and generating vivid stories out of them (Hu, Ericsson, Yang & Lu, 2009. Thus, 2-digit condition was included, with 1-digit numbers and letters as control conditions. We hypothesized that 2-digit condition in C.L. should elicit the strongest activity in the brain regions which are associated with his mnemonic. Functional MRI results revealed that bilateral frontal poles (FPs, BA10, left superior parietal lobule (SPL, left premotor cortex (PMC, and left dorsolateral prefrontal cortex (DLPFC, were more engaged in both the study and recall phase of 2-digit condition for C.L. relative to controls. Moreover, the left middle/inferior frontal gyri (M/IFG and intraparietal sulci (IPS were less engaged in the study phase of 2-digit condition for C.L. (vs. controls. These results suggested that C.L. relied more on brain regions that are associated with episodic memory other than verbal rehearsal while he used his mnemonic strategies. This study supported theoretical accounts of restructured cognitive mechanisms for the acquisition of superior memory performance.

Gastrointestinal digital fluoroscopy: Comparison of digital pulsed progressive readout images with 100-mm spot films

International Nuclear Information System (INIS)

Steiner, E.; Ferrucci, J.T.; Mueller, P.R.; Hahn, P.F.

1987-01-01

New developments in pulsed progressive readout (PPR) techniques allow short, extremely intense pulses of radiation to be used to produce a latent image which is then progressively read off the video camera and placed in 1,024 x 1,024-pixel digital storage. The resulting image is produced by a 10-20-msec pulse, reducing motion artifact to below that achievable with conventional spot film techniques, with a potential for 50%-95% dose reduction. This technique of reducing motion artifact is ideal for digital applications in gastrointestinal radiology. The authors compared 10-mm spot films and PPR digital radiographs of 86 anatomic regions in 43 patients undergoing routine barium enema and cholangiographic examinations. Parameters evaluated included display of normal and pathologic features, image contrast, and resolution. The benefits of the PPR technique include postprocessing to evaluate low contrast region and the potential for significant dose reduction

An improved three-dimensional non-scanning laser imaging system based on digital micromirror device

Science.gov (United States)

Xia, Wenze; Han, Shaokun; Lei, Jieyu; Zhai, Yu; Timofeev, Alexander N.

2018-01-01

Nowadays, there are two main methods to realize three-dimensional non-scanning laser imaging detection, which are detection method based on APD and detection method based on Streak Tube. However, the detection method based on APD possesses some disadvantages, such as small number of pixels, big pixel interval and complex supporting circuit. The detection method based on Streak Tube possesses some disadvantages, such as big volume, bad reliability and high cost. In order to resolve the above questions, this paper proposes an improved three-dimensional non-scanning laser imaging system based on Digital Micromirror Device. In this imaging system, accurate control of laser beams and compact design of imaging structure are realized by several quarter-wave plates and a polarizing beam splitter. The remapping fiber optics is used to sample the image plane of receiving optical lens, and transform the image into line light resource, which can realize the non-scanning imaging principle. The Digital Micromirror Device is used to convert laser pulses from temporal domain to spatial domain. The CCD with strong sensitivity is used to detect the final reflected laser pulses. In this paper, we also use an algorithm which is used to simulate this improved laser imaging system. In the last, the simulated imaging experiment demonstrates that this improved laser imaging system can realize three-dimensional non-scanning laser imaging detection.

A High-Dynamic-Range Optical Remote Sensing Imaging Method for Digital TDI CMOS

Directory of Open Access Journals (Sweden)

Taiji Lan

2017-10-01

Full Text Available The digital time delay integration (digital TDI technology of the complementary metal-oxide-semiconductor (CMOS image sensor has been widely adopted and developed in the optical remote sensing field. However, the details of targets that have low illumination or low contrast in scenarios of high contrast are often drowned out because of the superposition of multi-stage images in digital domain multiplies the read noise and the dark noise, thus limiting the imaging dynamic range. Through an in-depth analysis of the information transfer model of digital TDI, this paper attempts to explore effective ways to overcome this issue. Based on the evaluation and analysis of multi-stage images, the entropy-maximized adaptive histogram equalization (EMAHE algorithm is proposed to improve the ability of images to express the details of dark or low-contrast targets. Furthermore, in this paper, an image fusion method is utilized based on gradient pyramid decomposition and entropy weighting of different TDI stage images, which can improve the detection ability of the digital TDI CMOS for complex scenes with high contrast, and obtain images that are suitable for recognition by the human eye. The experimental results show that the proposed methods can effectively improve the high-dynamic-range imaging (HDRI capability of the digital TDI CMOS. The obtained images have greater entropy and average gradients.

A Low Power Digital Accumulation Technique for Digital-Domain CMOS TDI Image Sensor.

Science.gov (United States)

Yu, Changwei; Nie, Kaiming; Xu, Jiangtao; Gao, Jing

2016-09-23

In this paper, an accumulation technique suitable for digital domain CMOS time delay integration (TDI) image sensors is proposed to reduce power consumption without degrading the rate of imaging. In terms of the slight variations of quantization codes among different pixel exposures towards the same object, the pixel array is divided into two groups: one is for coarse quantization of high bits only, and the other one is for fine quantization of low bits. Then, the complete quantization codes are composed of both results from the coarse-and-fine quantization. The equivalent operation comparably reduces the total required bit numbers of the quantization. In the 0.18 µm CMOS process, two versions of 16-stage digital domain CMOS TDI image sensor chains based on a 10-bit successive approximate register (SAR) analog-to-digital converter (ADC), with and without the proposed technique, are designed. The simulation results show that the average power consumption of slices of the two versions are 6 . 47 × 10 - 8 J/line and 7 . 4 × 10 - 8 J/line, respectively. Meanwhile, the linearity of the two versions are 99.74% and 99.99%, respectively.

Computer processing of the scintigraphic image using digital filtering techniques

International Nuclear Information System (INIS)

Matsuo, Michimasa

1976-01-01

The theory of digital filtering was studied as a method for the computer processing of scintigraphic images. The characteristics and design techniques of finite impulse response (FIR) digital filters with linear phases were examined using the z-transform. The conventional data processing method, smoothing, could be recognized as one kind of linear phase FIR low-pass digital filtering. Ten representatives of FIR low-pass digital filters with various cut-off frequencies were scrutinized from the frequency domain in one-dimension and two-dimensions. These filters were applied to phantom studies with cold targets, using a Scinticamera-Minicomputer on-line System. These studies revealed that the resultant images had a direct connection with the magnitude response of the filter, that is, they could be estimated fairly well from the frequency response of the digital filter used. The filter, which was estimated from phantom studies as optimal for liver scintigrams using 198 Au-colloid, was successfully applied in clinical use for detecting true cold lesions and, at the same time, for eliminating spurious images. (J.P.N.)

Imaging Total Stations - Modular and Integrated Concepts

Science.gov (United States)

Hauth, Stefan; Schlüter, Martin

2010-05-01

Keywords: 3D-Metrology, Engineering Geodesy, Digital Image Processing Initialized in 2009, the Institute for Spatial Information and Surveying Technology i3mainz, Mainz University of Applied Sciences, forces research towards modular concepts for imaging total stations. On the one hand, this research is driven by the successful setup of high precision imaging motor theodolites in the near past, on the other hand it is pushed by the actual introduction of integrated imaging total stations to the positioning market by the manufacturers Topcon and Trimble. Modular concepts for imaging total stations are manufacturer independent to a large extent and consist of a particular combination of accessory hardware, software and algorithmic procedures. The hardware part consists mainly of an interchangeable eyepiece adapter offering opportunities for digital imaging and motorized focus control. An easy assembly and disassembly in the field is possible allowing the user to switch between the classical and the imaging use of a robotic total station. The software part primarily has to ensure hardware control, but several level of algorithmic support might be added and have to be distinguished. Algorithmic procedures allow to reach several levels of calibration concerning the geometry of the external digital camera and the total station. We deliver insight in our recent developments and quality characteristics. Both the modular and the integrated approach seem to have its individual strengths and weaknesses. Therefore we expect that both approaches might point at different target applications. Our aim is a better understanding of appropriate applications for robotic imaging total stations. First results are presented. Stefan Hauth, Martin Schlüter i3mainz - Institut für Raumbezogene Informations- und Messtechnik FH Mainz University of Applied Sciences Lucy-Hillebrand-Straße 2, 55128 Mainz, Germany

Cancer Digital Slide Archive: an informatics resource to support integrated in silico analysis of TCGA pathology data

Science.gov (United States)

Gutman, David A; Cobb, Jake; Somanna, Dhananjaya; Park, Yuna; Wang, Fusheng; Kurc, Tahsin; Saltz, Joel H; Brat, Daniel J; Cooper, Lee A D

2013-01-01

Background The integration and visualization of multimodal datasets is a common challenge in biomedical informatics. Several recent studies of The Cancer Genome Atlas (TCGA) data have illustrated important relationships between morphology observed in whole-slide images, outcome, and genetic events. The pairing of genomics and rich clinical descriptions with whole-slide imaging provided by TCGA presents a unique opportunity to perform these correlative studies. However, better tools are needed to integrate the vast and disparate data types. Objective To build an integrated web-based platform supporting whole-slide pathology image visualization and data integration. Materials and methods All images and genomic data were directly obtained from the TCGA and National Cancer Institute (NCI) websites. Results The Cancer Digital Slide Archive (CDSA) produced is accessible to the public (http://cancer.digitalslidearchive.net) and currently hosts more than 20 000 whole-slide images from 22 cancer types. Discussion The capabilities of CDSA are demonstrated using TCGA datasets to integrate pathology imaging with associated clinical, genomic and MRI measurements in glioblastomas and can be extended to other tumor types. CDSA also allows URL-based sharing of whole-slide images, and has preliminary support for directly sharing regions of interest and other annotations. Images can also be selected on the basis of other metadata, such as mutational profile, patient age, and other relevant characteristics. Conclusions With the increasing availability of whole-slide scanners, analysis of digitized pathology images will become increasingly important in linking morphologic observations with genomic and clinical endpoints. PMID:23893318

The Avocado Hand

LENUS (Irish Health Repository)

Rahmani, G

2017-11-01

Accidental self-inflicted knife injuries to digits are a common cause of tendon and nerve injury requiring hand surgery. There has been an apparent increase in avocado related hand injuries. Classically, the patients hold the avocado in their non-dominant hand while using a knife to cut\\/peel the fruit with their dominant hand. The mechanism of injury is usually a stabbing injury to the non-dominant hand as the knife slips past the stone, through the soft avocado fruit. Despite their apparent increased incidence, we could not find any cases in the literature which describe the “avocado hand”. We present a case of a 32-year-old woman who sustained a significant hand injury while preparing an avocado. She required exploration and repair of a digital nerve under regional anaesthesia and has since made a full recovery.

Digital image processing for real-time neutron radiography and its applications

International Nuclear Information System (INIS)

Fujine, Shigenori

1989-01-01

The present paper describes several digital image processing approaches for the real-time neutron radiography (neutron television-NTV), such as image integration, adaptive smoothing and image enhancement, which have beneficial effects on image improvements, and also describes how to use these techniques for applications. Details invisible in direct images of NTV are able to be revealed by digital image processing, such as reversed image, gray level correction, gray scale transformation, contoured image, subtraction technique, pseudo color display and so on. For real-time application a contouring operation and an averaging approach can also be utilized effectively. (author)

An overview of digital image processing in the field of nuclear medicine

International Nuclear Information System (INIS)

Okuyama, Yasuo

1992-01-01

The current status and remaining problems of digital image processing in nuclear medicine were discussed. Digitalization of nuclear medicine images has made it possible, in conjunction with computers, to obtain new information (Fourier analysis, Factor analysis, etc.) with added value from images, in place of the fixed concepts that had formerly been drawn only from images. However, the basis of this technology is the special QC and QA of nuclear medicine examinations, and those techniques have not yet been adequately established. The advantage of digitalization is the flexibility that comes from the programs, but the element of the subjectivity of each individual plays a large role, and it can be said that there is also the risk that the logic of image diagnosis established to date will be destroyed. Accordingly, the creation of digital image processing technique with specifications will give birth to standardized digital nuclear medicine images, and these development will certainly lead to progress in nuclear medicine diagnosis. In addition, in comparison with other modalities, the field of nuclear medicine involves a lesser amount of information, and this simplifiers the digitalization of images. At present, equipment is being designed and developed with incorporation of the concept of a work station. A serious problem that remains in this field is the standardization of image transmission. In summary, the main problem that must be solved in the field of nuclear medicine examinations is the establishment of QC and QA methods and practical algorithms for the software. It is hoped that there will be open access to information, etc., related to the software. (author)

Diagnostic ability of the periapical radiographs and digital image in the detection of the artificial proximal caries

International Nuclear Information System (INIS)

Heo, Min Suk; You, Dong Soo

1994-01-01

Recently, the digital image was introduced into radiological image. The digital image has the power of contrast enhancement, histogram control, and other digitally enhancement. At the point of the resolution, periapical radiograph is superior to the digital image, but enhanced digital procedure improves the diagnostic ability of the digital image. The purpose of this study was to evaluate the diagnostic ability of artificial proximal caries in conventional radiographs, digital radiographs and enhanced digital radiographs (histogram specification). ROC (Receiver Operating Characteristic) analysis and paired t-test were used for the evaluation of detectability, and following results were acquired: 1. The mean ROC area of conventional radiographs was 0.9274. 2. The mean ROC area of unenhanced digital image was 0.9168. 3. The mean ROC area of enhanced digital image was 0.9339. 4. The diagnostic ability of three imaging methods was not significant difference (p>0.05). So, the digital images had similar diagnostic ability of artificial proximal caries to conventional radiographs. If properly enhanced digital image, it may be superior to conventional radiographs.

Comparison of hand and semiautomatic tracing methods for creating maxillofacial artificial organs using sequences of computed tomography (CT) and cone beam computed tomography (CBCT) images.

Science.gov (United States)

Szabo, Bence T; Aksoy, Seçil; Repassy, Gabor; Csomo, Krisztian; Dobo-Nagy, Csaba; Orhan, Kaan

2017-06-09

The aim of this study was to compare the paranasal sinus volumes obtained by manual and semiautomatic imaging software programs using both CT and CBCT imaging. 121 computed tomography (CT) and 119 cone beam computed tomography (CBCT) examinations were selected from the databases of the authors' institutes. The Digital Imaging and Communications in Medicine (DICOM) images were imported into 3-dimensonal imaging software, in which hand mode and semiautomatic tracing methods were used to measure the volumes of both maxillary sinuses and the sphenoid sinus. The determined volumetric means were compared to previously published averages. Isometric CBCT-based volume determination results were closer to the real volume conditions, whereas the non-isometric CT-based volume measurements defined coherently lower volumes. By comparing the 2 volume measurement modes, the values gained from hand mode were closer to the literature data. Furthermore, CBCT-based image measurement results corresponded to the known averages. Our results suggest that CBCT images provide reliable volumetric information that can be depended on for artificial organ construction, and which may aid the guidance of the operator prior to or during the intervention.

Are digital images good enough? A comparative study of conventional film-screen vs digital radiographs on printed images of total hip replacement

Energy Technology Data Exchange (ETDEWEB)

Eklund, K.; Jonsson, K.; Lindblom, G.; Lundin, B.; Sanfridsson, J.; Sloth, M. [Department of Radiology, Center for Medical Imaging and Physiology, Lund University Hospital, 22185, Lund (Sweden); Sivberg, B. [Department of Nursing, Faculty of Medicine, Lund University, P.O. Box 157, 22100, Lund (Sweden)

2004-05-01

The aim of this study was to evaluate the inter- and intra-observer variability and to find differences in diagnostic safety between digital and analog technique in diagnostic zones around hip prostheses. In 80 patients who had had a total hip replacement (THR) for more than 2 years, a conventional image and a digital image were taken. Gruen's model of seven distinct regions of interest was used for evaluations. Five experienced radiologists observed the seven regions and noted in a protocol the following distances: stem-cement; cement-bone; and stem-bone. All images were printed on hard copies and were read twice. Weighted kappa, {kappa}{sub w}, analyses were used. The two most frequently loosening regions, stem-cement region 1 and cement-bone region 7, were closely analyzed. In region 1 the five observers had an agreement of 86.75-97.92% between analog and digital images in stem-cement, which is a varied {kappa}{sub w} 0.29-0.71. For cement-bone region 7 an agreement of 87.21-90.45% was found, which is a varied {kappa}{sub w} of 0.48-0.58. All the kappa values differ significantly from nil. The result shows that digital technique is as good as analog radiographs for diagnosing possible loosening of hip prostheses. (orig.)

Standard practice for digital imaging and communication in nondestructive evaluation (DICONDE) for digital radiographic (DR) test methods

CERN Document Server

American Society for Testing and Materials. Philadelphia

2010-01-01

1.1 This practice facilitates the interoperability of digital X-ray imaging equipment by specifying image data transfer and archival methods in commonly accepted terms. This document is intended to be used in conjunction with Practice E2339 on Digital Imaging and Communication in Nondestructive Evaluation (DICONDE). Practice E2339 defines an industrial adaptation of the NEMA Standards Publication titled Digital Imaging and Communications in Medicine (DICOM, see http://medical.nema.org), an international standard for image data acquisition, review, storage and archival storage. The goal of Practice E2339, commonly referred to as DICONDE, is to provide a standard that facilitates the display and analysis of NDE results on any system conforming to the DICONDE standard. Toward that end, Practice E2339 provides a data dictionary and a set of information modules that are applicable to all NDE modalities. This practice supplements Practice E2339 by providing information object definitions, information modules and a ...

78 FR 32427 - Notice of Issuance of Final Determination Concerning Multifunctional Digital Imaging Systems

Science.gov (United States)

2013-05-30

... multifunctional digital imaging systems for purposes of U.S. Government procurement. DATES: The final... Determination Concerning Multifunctional Digital Imaging Systems AGENCY: U.S. Customs and Border Protection... country of origin of certain multifunctional digital imaging systems. Based upon the facts presented, CBP...

Enhancement of digital radiography image quality using a convolutional neural network.

Science.gov (United States)

Sun, Yuewen; Li, Litao; Cong, Peng; Wang, Zhentao; Guo, Xiaojing

2017-01-01

Digital radiography system is widely used for noninvasive security check and medical imaging examination. However, the system has a limitation of lower image quality in spatial resolution and signal to noise ratio. In this study, we explored whether the image quality acquired by the digital radiography system can be improved with a modified convolutional neural network to generate high-resolution images with reduced noise from the original low-quality images. The experiment evaluated on a test dataset, which contains 5 X-ray images, showed that the proposed method outperformed the traditional methods (i.e., bicubic interpolation and 3D block-matching approach) as measured by peak signal to noise ratio (PSNR) about 1.3 dB while kept highly efficient processing time within one second. Experimental results demonstrated that a residual to residual (RTR) convolutional neural network remarkably improved the image quality of object structural details by increasing the image resolution and reducing image noise. Thus, this study indicated that applying this RTR convolutional neural network system was useful to improve image quality acquired by the digital radiography system.

Real-time digital x-ray subtraction imaging

International Nuclear Information System (INIS)

Mistretta, C.A.; Kruger, R.A.; Houk, T.L.

1982-01-01

A method of producing visible difference images derived from an x-ray image of an anatomical subject is described. X-rays are directed through the subject, and the image is converted into television fields comprising trains of analog video signals. The analog signals are converted into digital signals, which are then integrated over a predetermined time corresponding to several television fields. Difference video signals are produced by performing a subtraction between the ongoing video signals and the corresponding integrated signals, and are converted into visible television difference images representing changes in the x-ray image

Quantitative impact of direct, personal feedback on hand hygiene technique.

Science.gov (United States)

Lehotsky, Á; Szilágyi, L; Ferenci, T; Kovács, L; Pethes, R; Wéber, G; Haidegger, T

2015-09-01

This study investigated the effectiveness of targeting hand hygiene technique using a new training device that provides objective, personal and quantitative feedback. One hundred and thirty-six healthcare workers in three Hungarian hospitals participated in a repetitive hand hygiene technique assessment study. Ultraviolet (UV)-labelled hand rub was used at each event, and digital images of the hands were subsequently taken under UV light. Immediate objective visual feedback was given to participants, showing missed areas on their hands. The rate of inadequate hand rubbing reduced from 50% to 15% (P < 0.001). However, maintenance of this reduced rate is likely to require continuous use of the electronic equipment. Copyright © 2015 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

Feed particle size evaluation: conventional approach versus digital holography based image analysis

Directory of Open Access Journals (Sweden)

Vittorio Dell’Orto

2010-01-01

Full Text Available The aim of this study was to evaluate the application of image analysis approach based on digital holography in defining particle size in comparison with the sieve shaker method (sieving method as reference method. For this purpose ground corn meal was analyzed by a sieve shaker Retsch VS 1000 and by image analysis approach based on digital holography. Particle size from digital holography were compared with results obtained by screen (sieving analysis for each of size classes by a cumulative distribution plot. Comparison between particle size values obtained by sieving method and image analysis indicated that values were comparable in term of particle size information, introducing a potential application for digital holography and image analysis in feed industry.

Real-time digital X-ray subtraction imaging

International Nuclear Information System (INIS)

Mistretta, C.A.; Kruger, R.A.; Houk, T.L.

1979-01-01

A diagnostic anatomical X-ray apparatus comprising a converter and a television camera for converting an X-ray image of a subject into a series of television fields of video signals is described in detail. A digital memory system stores and integrates the video signals over a time interval corresponding to a plurality of successive television fields. The integrated video signals are recovered from storage and fed to a digital or analogue subtractor, the resulting output being displayed on a television monitor. Thus the display represents on-going changes in the anatomical X-ray image. In a modification, successive groups of fields are stored and integrated in three memories, cyclically, and subtractions are performed between successive pieces of integrated signals to provide a display of successive alterations in the X-ray image. For investigations of the heart, the integrating interval should be of the order of one cardiac cycle. (author)

Digital image correlation based on a fast convolution strategy

Science.gov (United States)

Yuan, Yuan; Zhan, Qin; Xiong, Chunyang; Huang, Jianyong

2017-10-01

In recent years, the efficiency of digital image correlation (DIC) methods has attracted increasing attention because of its increasing importance for many engineering applications. Based on the classical affine optical flow (AOF) algorithm and the well-established inverse compositional Gauss-Newton algorithm, which is essentially a natural extension of the AOF algorithm under a nonlinear iterative framework, this paper develops a set of fast convolution-based DIC algorithms for high-efficiency subpixel image registration. Using a well-developed fast convolution technique, the set of algorithms establishes a series of global data tables (GDTs) over the digital images, which allows the reduction of the computational complexity of DIC significantly. Using the pre-calculated GDTs, the subpixel registration calculations can be implemented efficiently in a look-up-table fashion. Both numerical simulation and experimental verification indicate that the set of algorithms significantly enhances the computational efficiency of DIC, especially in the case of a dense data sampling for the digital images. Because the GDTs need to be computed only once, the algorithms are also suitable for efficiently coping with image sequences that record the time-varying dynamics of specimen deformations.

Evaluation of display on CRT by various processing digital images

International Nuclear Information System (INIS)

Toyama, Yasuhiko; Akagi, Naoki; Ohara, Shuichi; Maeda, Tomoho; Kitazoe, Yasuhiro; Yamamoto, Kouji

1986-01-01

In this study, we digitized three sheets of thin line chart X-ray photographs altered the photographic density. By selecting the width of the photographic density at displaying the images on the CRT, We could augment the contrast of images and more easily recognize line images compared with original X-ray photos. This characteristic was clearly observed within the region of low wave length. Though the easy recognition was got by adjusting the contrast, the sharpness of line images was not in accordance with it. As mentioned above, we discussed the relation between the contrast and the sharpness of digitized images obtained with a multi-format camera. (author)

Evaluation of display on CRT by various processing digital images

Energy Technology Data Exchange (ETDEWEB)

Toyama, Yasuhiko; Akagi, Naoki; Ohara, Shuichi; Maeda, Tomoho; Kitazoe, Yasuhiro; Yamamoto, Kouji

1986-12-01

In this study, we digitized three sheets of thin line chart X-ray photographs altered the photographic density. By selecting the width of the photographic density at displaying the images on the CRT, We could augment the contrast of images and more easily recognize line images compared with original X-ray photos. This characteristic was clearly observed within the region of low wave length. Though the easy recognition was got by adjusting the contrast, the sharpness of line images was not in accordance with it. As mentioned above, we discussed the relation between the contrast and the sharpness of digitized images obtained with a multi-format camera.

Creating a panorama of the heart with digital images.

Science.gov (United States)

Rosebrock, L

2000-01-01

Digital imaging offers new opportunities still being discovered by users. This article describes a technique that was created using a digital camera to photograph the entire surface of a rat heart. The technique may have other applications as well.

Design, data, and theory regarding a digital hand inclinometer: a portable device for studying slant perception.

Science.gov (United States)

Li, Zhi; Durgin, Frank H

2011-06-01

Palm boards are often used as a nonverbal measure in human slant perception studies. It was recently found that palm boards are biased and relatively insensitive measures, and that an unrestricted hand gesture provides a more sensitive response (Durgin, Hajnal, Li, Tonge, & Stigliani, Acta Psychologica, 134, 182-197, 2010a). In this article, we describe an original design for a portable lightweight digital device for measuring hand orientation. This device is microcontroller-based and uses a micro inclinometer chip as its inclination sensor. The parts are fairly inexpensive. This device, used to measure hand orientation, provides a sensitive nonverbal method for studying slant perception, which can be used in both indoor and outdoor environments. We present data comparing the use of a free hand to palm-board and verbal measures for surfaces within reach and explain how to interpret free-hand measures for outdoor hills.

Iso-precision scaling of digitized mammograms to facilitate image analysis

International Nuclear Information System (INIS)

Karssmeijer, N.; van Erning, L.

1991-01-01

This paper reports on a 12 bit CCD camera equipped with a linear sensor of 4096 photodiodes which is used to digitize conventional mammographic films. An iso-precision conversion of the pixel values is preformed to transform the image data to a scale on which the image noise is equal at each level. For this purpose film noise and digitization noise have been determined as a function of optical density and pixel size. It appears that only at high optical densities digitization noise is comparable to or larger than film noise. The quantization error caused by compression of images recorded with 12 bits per pixel to 8 bit images by an iso-precision conversion has been calculated as a function of the number of quantization levels. For mammograms digitized in a 4096 2 matrix the additional error caused by such a scale transform is only about 1.5 percent. An iso-precision scale transform can be advantageous when automated procedures for quantitative image analysis are developed. Especially when detection of signals in noise is aimed at, a constant noise level over the whole pixel value range is very convenient. This is demonstrated by applying local thresholding to detect small microcalcifications. Results are compared to those obtained by using logarithmic or linearized scales

An experimental study on the readability of digital images in the furcal bone defects

Energy Technology Data Exchange (ETDEWEB)

Kang, Hyung Wuk; Hwang, Eui Hwan; Lee, Sang Rae [Kyunghee University College of Medicine, Seoul (Korea, Republic of)

2003-06-15

To evaluate and compare the efficacy of digital radiographic images in the detection of bone loss at the bifurcation area of the mandibular first molar with traditional film-based periapical radiographs. One dried human mandible with minimal periodontal bone loss around the first molar was selected and an artificial alveolar bone defect at the bifurcation area was serially prepared over 18 steps. Images were taken using a direct CCD-based system and with F-speed periapical films. The images were evaluated by seven interpreters (3 radiologists, 3 periodontologists, and 1 general dentist) using a 5-point confidence rating scale. The readability of both periapical radiographs and digital image increased as the size of the artificial lesion and exposure time increased (p<0.05). Periapical radiographs offered greater readability of smaller bone defects than digital images, and the coefficient of variation of mean score between periapical radiographs and digital images showed a significant difference. The experimental results indicate that a significant difference in the coefficient of variation of mean score exists between periapical radiographs and digital images, and that traditional film-based periapical images offer greater readability of smaller bone defects than digital images can presently offer.

An experimental study on the readability of digital images in the furcal bone defects

International Nuclear Information System (INIS)

Kang, Hyung Wuk; Hwang, Eui Hwan; Lee, Sang Rae

2003-01-01

To evaluate and compare the efficacy of digital radiographic images in the detection of bone loss at the bifurcation area of the mandibular first molar with traditional film-based periapical radiographs. One dried human mandible with minimal periodontal bone loss around the first molar was selected and an artificial alveolar bone defect at the bifurcation area was serially prepared over 18 steps. Images were taken using a direct CCD-based system and with F-speed periapical films. The images were evaluated by seven interpreters (3 radiologists, 3 periodontologists, and 1 general dentist) using a 5-point confidence rating scale. The readability of both periapical radiographs and digital image increased as the size of the artificial lesion and exposure time increased (p<0.05). Periapical radiographs offered greater readability of smaller bone defects than digital images, and the coefficient of variation of mean score between periapical radiographs and digital images showed a significant difference. The experimental results indicate that a significant difference in the coefficient of variation of mean score exists between periapical radiographs and digital images, and that traditional film-based periapical images offer greater readability of smaller bone defects than digital images can presently offer.

The Plastic Surgery Hand Curriculum.

Science.gov (United States)

Silvestre, Jason; Levin, L Scott; Serletti, Joseph M; Chang, Benjamin

2015-12-01

Designing an effective hand rotation for plastic surgery residents is difficult. The authors address this limitation by elucidating the critical components of the hand curriculum during plastic surgery residency. Hand questions on the Plastic Surgery In-Service Training Exam for six consecutive years (2008 to 2013) were characterized by presence of imaging, vignette setting, question taxonomy, answer domain, anatomy, and topic. Answer references were quantified by source and year of publication. Two hundred sixty-six questions were related to hand surgery (22.7 percent of all questions; 44.3 per year) and 61 were accompanied by an image (22.9 percent). Vignettes tended to be clinic- (50.0 percent) and emergency room-based (35.3 percent) (p < 0.001). Questions required decision-making (60.5 percent) over interpretation (25.9 percent) and recall skills (13.5 percent) (p < 0.001). Answers focused on interventions (57.5 percent) over anatomy/pathology (25.2 percent) and diagnoses (17.3 percent) (p < 0.001). Nearly half of the questions focused on the digits. The highest yield topics were trauma (35.3 percent), reconstruction (24.4 percent), and aesthetic and functional problems (14.2 percent). The Journal of Hand Surgery (American volume) (20.5 percent) and Plastic and Reconstructive Surgery (18.0 percent) were the most-cited journals, and the median publication lag was 7 years. Green's Operative Hand Surgery was the most-referenced textbook (41.8 percent). These results will enable trainees to study hand surgery topics with greater efficiency. Faculty can use these results to ensure that tested topics are covered during residency training. Thus, a benchmark is established to improve didactic, clinical, and operative experiences in hand surgery.

Application of Super-Resolution Image Reconstruction to Digital Holography

Directory of Open Access Journals (Sweden)

Zhang Shuqun

2006-01-01

Full Text Available We describe a new application of super-resolution image reconstruction to digital holography which is a technique for three-dimensional information recording and reconstruction. Digital holography has suffered from the low resolution of CCD sensors, which significantly limits the size of objects that can be recorded. The existing solution to this problem is to use optics to bandlimit the object to be recorded, which can cause the loss of details. Here super-resolution image reconstruction is proposed to be applied in enhancing the spatial resolution of digital holograms. By introducing a global camera translation before sampling, a high-resolution hologram can be reconstructed from a set of undersampled hologram images. This permits the recording of larger objects and reduces the distance between the object and the hologram. Practical results from real and simulated holograms are presented to demonstrate the feasibility of the proposed technique.

Monuments deterioration evaluation, using digited images. A methodology

Directory of Open Access Journals (Sweden)

Ángel, María C.

1995-12-01

Full Text Available In this work a methodology is proposed for data processing, integrating the techniques of digital images processing and the analytical capacity of graphical referencing systems and relational databases, in relation with the monuments. The images are generated using the digital image processing and they are included into a graphical data processing systems associated with a database containing the characteristics of the ashars or constituent elements. By combination of the images with the database induced properties the information is processed. The results are thematic maps that we save such as images. These maps are layers of new information (deduced levels. The elaboration of these maps allows attacking the problems of the restoration, renovation or treatment of the different monumental spaces on a global way, paying special attention on the most gravely affected areas.

En este trabajo se propone una metodología para el tratamiento de la información, integrando las técnicas de proceso digital de imágenes, la capacidad de análisis de los sistemas de referenciación gráfica y las bases de datos relacionales, referidas a monumentos. Para ello se elaboran las imágenes base por algoritmos propios del proceso digital, incluyendo aquellas en una aplicación especifica que asocia cada capa a una base de datos con las propiedades petrofísicas, hídricas, etc., o bien entre si, dando lugar a mapas temáticos. La generación de estos mapas permite abordar los problemas de restauración, rehabilitación o tratamiento de los diferentes espacios monumentales de forma global, con incidencia especial en las zonas más afectadas.

Twin-image reduction in inline digital holography using an object segmentation heuristic

International Nuclear Information System (INIS)

McElhinney, Conor P; Hennelly, Bryan M; Naughton, Thomas J

2008-01-01

We present a digital image processing heuristic for the removal of the twin-image in inline digital holograms. Typically, the unwanted twin manifests itself as visible corruptive noise in the reconstruction plane. We reconstruct the unwanted twin-image at its in-focus plane and suppress it by first finding the boundary of the object, and then removing the optical energy within this boundary. In this plane, the wanted twin-image optical energy is largely dispersed outside this boundary and so it is retained. The heuristic's effectiveness is demonstrated using a digital hologram of a real-world object.

Twin-image reduction in inline digital holography using an object segmentation heuristic

Energy Technology Data Exchange (ETDEWEB)

McElhinney, Conor P; Hennelly, Bryan M [Department of Computer Science, National University of Ireland, Maynooth, County Kildare (Ireland); Naughton, Thomas J [University of Oulu, RFMedia Laboratory, Oulu Southern Institute, Vierimaantie 5, 84100 Ylivieska (Finland)], E-mail: conormce@cs.nuim.ie, E-mail: tomn@cs.nuim.ie

2008-11-01

We present a digital image processing heuristic for the removal of the twin-image in inline digital holograms. Typically, the unwanted twin manifests itself as visible corruptive noise in the reconstruction plane. We reconstruct the unwanted twin-image at its in-focus plane and suppress it by first finding the boundary of the object, and then removing the optical energy within this boundary. In this plane, the wanted twin-image optical energy is largely dispersed outside this boundary and so it is retained. The heuristic's effectiveness is demonstrated using a digital hologram of a real-world object.

Digital radiography versus conventional radiography during excretory urography: our experience

International Nuclear Information System (INIS)

Cervi, P.M.; Bighi, S.; Merlo, L.; Lupi, L.; Vita, G.

1990-01-01

The authors describe a computed radiographic system employed to generate and archive digital images in intravenous urography. For each exposure the system produces two digital images: the first (left image) simulates a conventional screen-film radiograph, the second (right image); enhances some spatial frequencies and emphasizes the margins of the structures. These images can be modified in their chief parameters and then printed by a laser-printer and archived on optical disks. Four experienced radiologists evaluated digital images with regard to some chief diagnostic parameters and, in 50 patients, they compared digital images with conventional screen-film radiographs and submitted the results to statistical analysis. For some of the chosen parameters, particularly for the evaluation of renal margins before and after contrast medium injection, digital images gave statistically better results than conventional films, while, no statistically significant different was observed for the other parameters. From the results of this preliminary study digital radiography was found to be useful in intravenous urography by reducing the patient's exposition dose, by always obtaining images of good quality, and by enhancing some particular features of the standard image; on the other hand there were many unsolved problems regarding the communicating and archiving system (PACS), because of the slowness of the image transfer procedure, difficulties in data transmission and complexity of referential procedures

A dual-view digital tomosynthesis imaging technique for improved chest imaging

Energy Technology Data Exchange (ETDEWEB)

Zhong, Yuncheng; Lai, Chao-Jen; Wang, Tianpeng; Shaw, Chris C., E-mail: cshaw@mdanderson.org [Department of Imaging Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas 77054 (United States)

2015-09-15

Purpose: Digital tomosynthesis (DTS) has been shown to be useful for reducing the overlapping of abnormalities with anatomical structures at various depth levels along the posterior–anterior (PA) direction in chest radiography. However, DTS provides crude three-dimensional (3D) images that have poor resolution in the lateral view and can only be displayed with reasonable quality in the PA view. Furthermore, the spillover of high-contrast objects from off-fulcrum planes generates artifacts that may impede the diagnostic use of the DTS images. In this paper, the authors describe and demonstrate the use of a dual-view DTS technique to improve the accuracy of the reconstructed volume image data for more accurate rendition of the anatomy and slice images with improved resolution and reduced artifacts, thus allowing the 3D image data to be viewed in views other than the PA view. Methods: With the dual-view DTS technique, limited angle scans are performed and projection images are acquired in two orthogonal views: PA and lateral. The dual-view projection data are used together to reconstruct 3D images using the maximum likelihood expectation maximization iterative algorithm. In this study, projection images were simulated or experimentally acquired over 360° using the scanning geometry for cone beam computed tomography (CBCT). While all projections were used to reconstruct CBCT images, selected projections were extracted and used to reconstruct single- and dual-view DTS images for comparison with the CBCT images. For realistic demonstration and comparison, a digital chest phantom derived from clinical CT images was used for the simulation study. An anthropomorphic chest phantom was imaged for the experimental study. The resultant dual-view DTS images were visually compared with the single-view DTS images and CBCT images for the presence of image artifacts and accuracy of CT numbers and anatomy and quantitatively compared with root-mean-square-deviation (RMSD) values

Network based multi-channel digital flash X-ray imaging system

International Nuclear Information System (INIS)

Wang Jingjin; Yuan Jie; Liu Yaqiang; Lin Yong; Song Zheng; Liu Keyin; Zhang Qi; Zheng Futang

2000-01-01

A network based multi-channel digital flash X-ray imaging system has been developed. It can be used to acquire and digitize orthogonal flash X-ray images in multi-interval, and to distribute the images on the network. There is no need of films and chemical process, no anxiety of waiting and no trouble of film archiving. This system is useful for testing ballistics, jet, explode, armour-piercing and fast running machines. The system composing and acquired images are presented. The software for object separating, mass calculating, 3D positioning, speed determining and cavity reconstruction are described

Network based multi-channel digital flash X-ray imaging system

International Nuclear Information System (INIS)

Wang Jingjin; Yuan Jie; Liu Yaqiang; Lin Yong; Song Zheng; Liu Keyin

2003-01-01

A network based multi-channel digital flash X-ray imaging system has been developed. It can be used to acquire and digitize orthogonal flash X-ray images in multi-interval, and to distribute the images on the network. There is no need of films and chemical process, no anxiety of waiting and no trouble of film archiving. This system is useful for testing ballistics, jet, explode, armour-piercing and fast running machines. The system composing and acquired images of terminal ballistics are presented. The software for object separating, profile calculating and 3D cavity reconstruction are described

How to optimize radiological images captured from digital cameras, using the Adobe Photoshop 6.0 program.

Science.gov (United States)

Chalazonitis, A N; Koumarianos, D; Tzovara, J; Chronopoulos, P

2003-06-01

Over the past decade, the technology that permits images to be digitized and the reduction in the cost of digital equipment allows quick digital transfer of any conventional radiological film. Images then can be transferred to a personal computer, and several software programs are available that can manipulate their digital appearance. In this article, the fundamentals of digital imaging are discussed, as well as the wide variety of optional adjustments that the Adobe Photoshop 6.0 (Adobe Systems, San Jose, CA) program can offer to present radiological images with satisfactory digital imaging quality.

Noninvasive imaging of human skin hemodynamics using a digital red-green-blue camera

Science.gov (United States)

Nishidate, Izumi; Tanaka, Noriyuki; Kawase, Tatsuya; Maeda, Takaaki; Yuasa, Tomonori; Aizu, Yoshihisa; Yuasa, Tetsuya; Niizeki, Kyuichi

2011-08-01

In order to visualize human skin hemodynamics, we investigated a method that is specifically developed for the visualization of concentrations of oxygenated blood, deoxygenated blood, and melanin in skin tissue from digital RGB color images. Images of total blood concentration and oxygen saturation can also be reconstructed from the results of oxygenated and deoxygenated blood. Experiments using tissue-like agar gel phantoms demonstrated the ability of the developed method to quantitatively visualize the transition from an oxygenated blood to a deoxygenated blood in dermis. In vivo imaging of the chromophore concentrations and tissue oxygen saturation in the skin of the human hand are performed for 14 subjects during upper limb occlusion at 50 and 250 mm Hg. The response of the total blood concentration in the skin acquired by this method and forearm volume changes obtained from the conventional strain-gauge plethysmograph were comparable during the upper arm occlusion at pressures of both 50 and 250 mm Hg. The results presented in the present paper indicate the possibility of visualizing the hemodynamics of subsurface skin tissue.

Digital processing of radiographic images

Science.gov (United States)

Bond, A. D.; Ramapriyan, H. K.

1973-01-01

Some techniques are presented and the software documentation for the digital enhancement of radiographs. Both image handling and image processing operations are considered. The image handling operations dealt with are: (1) conversion of format of data from packed to unpacked and vice versa; (2) automatic extraction of image data arrays; (3) transposition and 90 deg rotations of large data arrays; (4) translation of data arrays for registration; and (5) reduction of the dimensions of data arrays by integral factors. Both the frequency and the spatial domain approaches are presented for the design and implementation of the image processing operation. It is shown that spatial domain recursive implementation of filters is much faster than nonrecursive implementations using fast fourier transforms (FFT) for the cases of interest in this work. The recursive implementation of a class of matched filters for enhancing image signal to noise ratio is described. Test patterns are used to illustrate the filtering operations. The application of the techniques to radiographic images of metallic structures is demonstrated through several examples.

Application of the Digital Image Technology in the Visual Monitoring and Prediction of Shuttering Construction Safety

Science.gov (United States)

Ummin, Okumura; Tian, Han; Zhu, Haiyu; Liu, Fuqiang

2018-03-01

Construction safety has always been the first priority in construction process. The common safety problem is the instability of the template support. In order to solve this problem, the digital image measurement technology has been contrived to support real-time monitoring system which can be triggered if the deformation value exceed the specified range. Thus the economic loss could be reduced to the lowest level.

Digital color image encoding and decoding using a novel chaotic random generator

International Nuclear Information System (INIS)

Nien, H.H.; Huang, C.K.; Changchien, S.K.; Shieh, H.W.; Chen, C.T.; Tuan, Y.Y.

2007-01-01

This paper proposes a novel chaotic system, in which variables are treated as encryption keys in order to achieve secure transmission of digital color images. Since the dynamic response of chaotic system is highly sensitive to the initial values of a system and to the variation of a parameter, and chaotic trajectory is so unpredictable, we use elements of variables as encryption keys and apply these to computer internet communication of digital color images. As a result, we obtain much higher communication security. We adopt one statistic method involving correlation coefficient γ and FIPS PUB 140-1 to test on the distribution of distinguished elements of variables for continuous-time chaotic system, and accordingly select optimal encryption keys to use in secure communication of digital color images. At the transmitter end, we conduct RGB level decomposition on digital color images, and encrypt them with chaotic keys, and finally transmit them through computer internet. The same encryption keys are used to decrypt and recover the original images at the receiver end. Even if the encrypted images are stolen in the public channel, an intruder is not able to decrypt and recover the original images because of the lack of adequate encryption keys. Empirical example shows that the chaotic system and encryption keys applied in the encryption, transmission, decryption, and recovery of digital color images can achieve higher communication security and best recovered images

Watermarking Techniques Using Least Significant Bit Algorithm for Digital Image Security Standard Solution- Based Android

Directory of Open Access Journals (Sweden)

Ari Muzakir

2017-05-01

Full Text Available Ease of deployment of digital image through the internet has positive and negative sides, especially for owners of the original digital image. The positive side of the ease of rapid deployment is the owner of that image deploys digital image files to various sites in the world address. While the downside is that if there is no copyright that serves as protector of the image it will be very easily recognized ownership by other parties. Watermarking is one solution to protect the copyright and know the results of the digital image. With Digital Image Watermarking, copyright resulting digital image will be protected through the insertion of additional information such as owner information and the authenticity of the digital image. The least significant bit (LSB is one of the algorithm is simple and easy to understand. The results of the simulations carried out using android smartphone shows that the LSB watermarking technique is not able to be seen by naked human eye, meaning there is no significant difference in the image of the original files with images that have been inserted watermarking. The resulting image has dimensions of 640x480 with a bit depth of 32 bits. In addition, to determine the function of the ability of the device (smartphone in processing the image using this application used black box testing. 

Effects of Carpal Tunnel Syndrome on adaptation of multi-digit forces to object mass distribution for whole-hand manipulation

Directory of Open Access Journals (Sweden)

Zhang Wei

2012-11-01

Full Text Available Abstract Background Carpal tunnel syndrome (CTS is a compression neuropathy of the median nerve that results in sensorimotor deficits in the hand. Until recently, the effects of CTS on hand function have been studied using mostly two-digit grip tasks. The purpose of this study was to investigate the coordination of multi-digit forces as a function of object center of mass (CM during whole-hand grasping. Methods Fourteen CTS patients and age- and gender-matched controls were instructed to grasp, lift, hold, and release a grip device with five digits for seven consecutive lifts while maintaining its vertical orientation. The object CM was changed by adding a mass at different locations at the base of the object. We measured forces and torques exerted by each digit and object kinematics and analyzed modulation of these variables to object CM at object lift onset and during object hold. Our task requires a modulation of digit forces at and after object lift onset to generate a compensatory moment to counteract the external moment caused by the added mass and to minimize object tilt. Results We found that CTS patients learned to generate a compensatory moment and minimized object roll to the same extent as controls. However, controls fully exploited the available degrees of freedom (DoF in coordinating their multi-digit forces to generate a compensatory moment, i.e., digit normal forces, tangential forces, and the net center of pressure on the finger side of the device at object lift onset and during object hold. In contrast, patients modulated only one of these DoFs (the net center of pressure to object CM by modulating individual normal forces at object lift onset. During object hold, however, CTS patients were able to modulate digit tangential force distribution to object CM. Conclusions Our findings suggest that, although CTS did not affect patients’ ability to perform our manipulation task, it interfered with the modulation of specific grasp

Diagnostic imaging of the hand. 3. rev. and enl. ed.; Bildgebende Diagnostik der Hand

Energy Technology Data Exchange (ETDEWEB)

Schmitt, Rainer [Herz und Gefaessklinik GmbH, Bad Neustadt (Germany). Klinik fuer Diagnostische und Interventionelle Radiologie; Lanz, Ulrich

2015-07-01

The book on diagnostic imaging of the hand covers the following issues: projection radiography, cinematography, MRT and CR arthrography, arthroscopy, arteriography, skeleton scintiscanning, sonography, computerized tomography, magnetic resonance tomography, anatomy of forearm and carpus, anatomy of metacarpus and fingers, carpal function and morphometry, postoperative X-ray diagnostic, growing hand skeleton, normative variants, malformations and deformities, trauma of the distal forearm, lesions of the ulnocarpal complex (TFCC), scaphoid fractures, scaphoid arthrosis, fractures of other carpus bones, carpal luxations and luxation fractures, carpal instabilities, fractures of the metacarpalla, finger fractures, arthrosis deformans, enthesiopathies, sport induced soft tissue lesions, osteonecrosis, impingement syndromes, osteopenic skeletal diseases, metabolis diseases, crystal-induced osteoarthropaties, rheumatoid arthritis, spondyloarthritis, rheumatic fever, collagenoses, infective arthritis, osteomyelitis, soft tissue infections, cystoids bone lesions, skeletal tumors, soft tissue tumors, carpal tunnel syndrome, nerve compression syndrome, arterial perfusion disturbances, differential diagnostic tables on hand lesions.

A survey of passive technology for digital image forensics

Institute of Scientific and Technical Information of China (English)

LUO Weiqi; QU Zhenhua; PAN Feng; HUANG Jiwu

2007-01-01

Over the past years,digital images have been widely used in the Internet and other applications.Whilst image processing techniques are developing at a rapid speed,tampering with digital images without leaving any obvious traces becomes easier and easier.This may give rise to some problems such as image authentication.A new passive technology for image forensics has evolved quickly during the last few years.Unlike the signature-based or watermark-based methods,the new technology does not need any signature generated or watermark embedded in advance,it assumes that different imaging devices or processing would introduce different inherent patterns into the output images.These underlying patterns are consistent in the original untampered images and would be altered after some kind of manipulations.Thus,they can be used as evidence for image source identification and alteration detection.In this paper,we will discuss this new forensics technology and give an overview of the prior literatures.Some concluding remarks are made about the state of the art and the challenges in this novel technology.

Patient doses in digital cardiac imaging

International Nuclear Information System (INIS)

Huda, W.; Ogden, K.M.; Roskopf, M.L.; Phadke, K.

2001-01-01

In this pilot study, we obtained estimates of entrance skin doses and the corresponding effective doses to patients undergoing digital cardiac imaging procedures on a GE Advantx LC/LP Plus system. Data were obtained for six patients undergoing diagnostic examinations and six patients who had interventional procedures. For each patient examination, radiographic techniques for fluoroscopic and digital cine imaging were recorded, together with the irradiation geometry. The projection with the highest exposure resulted in an average skin dose of 0.64 ± 0.41 Gy (maximum of 1.6 Gy). The average patient skin doses taking into account overlapping projections was 1.1 ± 0.8 Gy (maximum of 3.0 Gy). The exposure area product (EAP) incident on the patient was converted into the energy imparted to the patient and the corresponding effective dose. The average patient effective dose was 28 ± 14 mSv (maximum 62 mSv), with the resultant average fatal cancer risk estimated to be of the order of 8x10 -3 . Average doses for interventional procedures in cardiac imaging are higher than those associated with diagnostic examinations by approximately 50%. (author)

Crack Detection by Digital Image Processing

DEFF Research Database (Denmark)

Lyngbye, Janus; Brincker, Rune

It is described how digital image processing is used for measuring the length of fatigue cracks. The system is installed in a Personal, Computer equipped with image processing hardware and performs automated measuring on plane metal specimens used in fatigue testing. Normally one can not achieve...... a resolution better than that of the image processing equipment. To overcome this problem an extrapolation technique is used resulting in a better resolution. The system was tested on a specimen loaded with different loads. The error σa was less than 0.031 mm, which is of the same size as human measuring...

Thinning an object boundary on digital image using pipelined algorithm

International Nuclear Information System (INIS)

Dewanto, S.; Aliyanta, B.

1997-01-01

In digital image processing, the thinning process to an object boundary is required to analyze the image structure with a measurement of parameter such as area, circumference of the image object. The process needs a sufficient large memory and time consuming if all the image pixels stored in the memory and the following process is done after all the pixels has ben transformed. pipelined algorithm can reduce the time used in the process. This algorithm uses buffer memory where its size can be adjusted. the next thinning process doesn't need to wait all the transformation of pixels. This paper described pipelined algorithm with some result on the use of the algorithm to digital image

Latin American image quality survey in digital mammography studies

International Nuclear Information System (INIS)

Mora, Patricia; Khoury, Helen; Bitelli, Regina; Quintero, Ana Rosa; Garay, Fernando; Garcia Aguilar, Juan; Gamarra, Mirtha; Ubeda, Carlos

2017-01-01

Under International Atomic Energy Agency regional programme TSA3 Radiological Protection of Patients in Medical Exposures, Latin American countries evaluated the image quality and glandular doses for digital mammography equipment with the purpose of seeing the performance and compliance with international recommendations. Totally, 24 institutions participated from Brazil, Chile, Costa Rica, El Salvador, Mexico, Paraguay and Venezuela. Signal difference noise ratio results showed for CR poor compliance with tolerances; better results were obtained for full-field digital mammography equipment. Mean glandular dose results showed that the majority of units have values below the acceptable dose levels. This joint Latin American project identified common problems: difficulty in working with digital images and lack of specific training by medical physicists from the region. Image quality is a main issue not being satisfied in accordance with international recommendations; optimisation processes in which the doses are increased should be very carefully done in order to improve early detection of any cancer signs. (authors)

Survey of best practices in digital image collection management, 2016 edition

CERN Document Server

2016-01-01

The study presents data and commentary from 55 institutions that manage digital image collections, including museums, historical societies, botanic gardens, churches colleges and universities, government agencies and others. The study looks at a broad range of issues in cataloging, findability, marketing, revenue generation, technology use, rights, digitization, staffing, budgets, access, preservation, image collection building and many other issues of interest to administrators of large digital image collections. Just a few of the report's many findings are that: Only 9.1% of the institutions sampled acquire images from imaging vendors; mostly this was done by college and university collections in the United States; 10% of the institutions sampled had annual revenues from image sales and licensing that exceeded 50,000; No organization in the sample chose outsourced vendor scanning as their primary means of building their collections though 14.55% chose it second and 12.73% ranked it third; 43.64% of those s...

Screening for diabetic retinopathy in rural area using single-field, digital fundus images.

Science.gov (United States)

Ruamviboonsuk, Paisan; Wongcumchang, Nattapon; Surawongsin, Pattamaporn; Panyawatananukul, Ekchai; Tiensuwan, Montip

2005-02-01

To evaluate the practicability of using single-field, 2.3 million-pixel, digital fundus images for screening of diabetic retinopathy in rural areas. All diabetic patients who regularly attended the diabetic clinic at Kabcheang Community Hospital, located at 15 kilometers from the Thailand-Cambodia border, were appointed to the hospital for a 3-day diabetic retinopathy screening programme. The fundi of all patients were captured in single-field, 45 degrees, 2.3 million-pixel images using nonmydriatic digital fundus camera and then sent to a reading center in Bangkok. The fundi were also examined through dilated pupils by a retinal specialist at this hospital. The grading of diabetic retinopathy from two methods was compared for an exact agreement. The average duration of single digital fundus image capture was 2 minutes. The average file size of each image was 750 kilobytes. The average duration of single image transmission to a reading center in Bangkok via satellite was 3 minutes; via a conventional telephone line was 8 minutes. Of all 150 patients, 130 were assessed for an agreement between dilated fundus examination and digital fundus images in diagnosis of diabetic retinopathy. The exact agreement was 0.87, the weighted kappa statistics was 0.74. The sensitivity of digital fundus images in detecting diabetic retinopathy was 80%, the specificity was 96%. For diabetic macular edema the exact agreement was 0.97, the weighted kappa was 0.43, the sensitivity was 43%, and the specificity was 100%. The image capture of the nonmydriatic digital fundus camera is suitable for screening of diabetic retinopathy and single-field digital fundus images are potentially acceptable tools for the screening. The real-time image transmission via telephone lines to remote reading center, however, may not be practical for routine diabetic retinopathy screening in rural areas.