WorldWideScience

Sample records for player streaming video

  1. ADAPTIVE STREAMING OVER HTTP (DASH UNTUK APLIKASI VIDEO STREAMING

    Directory of Open Access Journals (Sweden)

    I Made Oka Widyantara

    2015-12-01

    Full Text Available This paper aims to analyze Internet-based streaming video service in the communication media with variable bit rates. The proposed scheme on Dynamic Adaptive Streaming over HTTP (DASH using the internet network that adapts to the protocol Hyper Text Transfer Protocol (HTTP. DASH technology allows a video in the video segmentation into several packages that will distreamingkan. DASH initial stage is to compress the video source to lower the bit rate video codec uses H.26. Video compressed further in the segmentation using MP4Box generates streaming packets with the specified duration. These packages are assembled into packets in a streaming media format Presentation Description (MPD or known as MPEG-DASH. Streaming video format MPEG-DASH run on a platform with the player bitdash teritegrasi bitcoin. With this scheme, the video will have several variants of the bit rates that gave rise to the concept of scalability of streaming video services on the client side. The main target of the mechanism is smooth the MPEG-DASH streaming video display on the client. The simulation results show that the scheme based scalable video streaming MPEG-DASH able to improve the quality of image display on the client side, where the procedure bufering videos can be made constant and fine for the duration of video views

  2. Streaming-video produktion

    DEFF Research Database (Denmark)

    Grønkjær, Poul

    2004-01-01

     E-learning Lab på Aalborg Universitet har i forbindelse med forskningsprojektet Virtuelle Læringsformer og Læringsmiljøer foretaget en række praktiske eksperimenter med streaming-video produktioner. Hensigten med denne artikel er at formidle disse erfaringer. Artiklen beskriver hele produktionsf...... E-learning Lab på Aalborg Universitet har i forbindelse med forskningsprojektet Virtuelle Læringsformer og Læringsmiljøer foretaget en række praktiske eksperimenter med streaming-video produktioner. Hensigten med denne artikel er at formidle disse erfaringer. Artiklen beskriver hele...... produktionsforløbet: fra ide til færdigt produkt, forskellige typer af præsentationer, dramaturgiske overvejelser samt en konceptskitse. Streaming-video teknologien er nu så udviklet med et så tilfredsstillende audiovisuelt udtryk at vi kan begynde at fokusere på, hvilket indhold der er velegnet til at blive gjort...... tilgængeligt uafhængigt af tid og sted. Afslutningsvis er der en række kildehenvisninger, blandt andet en oversigt over de streaming-video produktioner, som denne artikel bygger på....

  3. Streaming-video produktion

    Directory of Open Access Journals (Sweden)

    Poul Grønkjær

    2004-05-01

    Full Text Available

    Første gang publiceret i UNEV nr. 3: Internet Video: Teknik og pædagogik mødes på nettet, april - juni 2004, red. Jens Dørup. ISSN 1603-5518.

    E-learning Lab på Aalborg Universitet har i forbindelse med forskningsprojektet Virtuelle Læringsformer og Læringsmiljøer foretaget en række praktiske eksperimenter med streaming-video produktioner. Hensigten med denne artikel er at formidle disse erfaringer. Artiklen beskriver hele produktionsforløbet: fra ide til færdigt produkt, forskellige typer af præsentationer, dramaturgiske overvejelser samt en konceptskitse. Streaming-video teknologien er nu så udviklet med et så tilfredsstillende audiovisuelt udtryk at vi kan begynde at fokusere på, hvilket indhold der er velegnet til at blive gjort tilgængeligt uafhængigt af tid og sted. Afslutningsvis er der en række kildehenvisninger, blandt andet en oversigt over de streaming-video produktioner, som denne artikel bygger på.

  4. We All Stream for Video

    Science.gov (United States)

    Technology & Learning, 2008

    2008-01-01

    More than ever, teachers are using digital video to enhance their lessons. In fact, the number of schools using video streaming increased from 30 percent to 45 percent between 2004 and 2006, according to Market Data Retrieval. Why the popularity? For starters, video-streaming products are easy to use. They allow teachers to punctuate lessons with…

  5. Video Player Keyboard Shortcuts: MedlinePlus

    Science.gov (United States)

    ... page: https://medlineplus.gov/hotkeys.html Video Player Keyboard Shortcuts To use the sharing features on this ... enable JavaScript. MedlinePlus offers a set of accessible keyboard shortcuts for our latest Health videos on the ...

  6. MEKANISME SEGMENTASI LAJU BIT PADA DYNAMIC ADAPTIVE STREAMING OVER HTTP (DASH UNTUK APLIKASI VIDEO STREAMING

    Directory of Open Access Journals (Sweden)

    Muhammad Audy Bazly

    2015-12-01

    Full Text Available This paper aims to analyze Internet-based streaming video service in the communication media with variable bit rates. The proposed scheme on Dynamic Adaptive Streaming over HTTP (DASH using the internet network that adapts to the protocol Hyper Text Transfer Protocol (HTTP. DASH technology allows a video in the video segmentation into several packages that will distreamingkan. DASH initial stage is to compress the video source to lower the bit rate video codec uses H.26. Video compressed further in the segmentation using MP4Box generates streaming packets with the specified duration. These packages are assembled into packets in a streaming media format Presentation Description (MPD or known as MPEG-DASH. Streaming video format MPEG-DASH run on a platform with the player bitdash teritegrasi bitcoin. With this scheme, the video will have several variants of the bit rates that gave rise to the concept of scalability of streaming video services on the client side. The main target of the mechanism is smooth the MPEG-DASH streaming video display on the client. The simulation results show that the scheme based scalable video streaming MPEG- DASH able to improve the quality of image display on the client side, where the procedure bufering videos can be made constant and fine for the duration of video views

  7. Video Streaming in Online Learning

    Science.gov (United States)

    Hartsell, Taralynn; Yuen, Steve Chi-Yin

    2006-01-01

    The use of video in teaching and learning is a common practice in education today. As learning online becomes more of a common practice in education, streaming video and audio will play a bigger role in delivering course materials to online learners. This form of technology brings courses alive by allowing online learners to use their visual and…

  8. Video Streaming in Online Learning

    Science.gov (United States)

    Hartsell, Taralynn; Yuen, Steve Chi-Yin

    2006-01-01

    The use of video in teaching and learning is a common practice in education today. As learning online becomes more of a common practice in education, streaming video and audio will play a bigger role in delivering course materials to online learners. This form of technology brings courses alive by allowing online learners to use their visual and…

  9. Efficient Video Indexing on the Web: A System that Leverages User Interactions with a Video Player

    CERN Document Server

    Leftheriotis, Ioannis; Chorianopoulos, Konstantinos

    2012-01-01

    In this paper, we propose a user-based video indexing method, that automatically generates thumbnails of the most important scenes of an online video stream, by analyzing users' interactions with a web video player. As a test bench to verify our idea we have extended the YouTube video player into the VideoSkip system. In addition, VideoSkip uses a web-database (Google Application Engine) to keep a record of some important parameters, such as the timing of basic user actions (play, pause, skip). Moreover, we implemented an algorithm that selects representative thumbnails. Finally, we populated the system with data from an experiment with nine users. We found that the VideoSkip system indexes video content by leveraging implicit users interactions, such as pause and thirty seconds skip. Our early findings point toward improvements of the web video player and its thumbnail generation technique. The VideSkip system could compliment content-based algorithms, in order to achieve efficient video-indexing in difficul...

  10. Stream Station video server system; Video saba sochi `Stream station`

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    A video server system Stream Station is developed for delivering moving images to the client on the VOD (video on demand) basis. In this system, video data compressed using the MPEG (Moving Picture Experts Group) technique are stored in a RAID (redundant arrays of independent disks) system, and is outputted as analog video data after expansion in a decoder provided at the output stage. The server system easily realizes a VOD system using the existing in-house cable TV facilities for instance for hotel rooms. The data for this purpose may be either in the MPEG1 or MPEG2 format, pictures may be simultaneously transmitted via as many as 32 channels at the maximum, and the storage holds 256 gigabytes at the maximum. It incorporates a video server architecture developed by Toshiba Corporation, and the data transfer rate from data readout to transmission is totally warranted. (translated by NEDO)

  11. High Definition Video Streaming Using H.264 Video Compression

    OpenAIRE

    Bechqito, Yassine

    2009-01-01

    This thesis presents high definition video streaming using H.264 codec implementation. The experiment carried out in this study was done for an offline streaming video but a model for live high definition streaming is introduced, as well. Prior to the actual experiment, this study describes digital media streaming. Also, the different technologies involved in video streaming are covered. These include streaming architecture and a brief overview on H.264 codec as well as high definition t...

  12. Maximizing Resource Utilization in Video Streaming Systems

    Science.gov (United States)

    Alsmirat, Mohammad Abdullah

    2013-01-01

    Video streaming has recently grown dramatically in popularity over the Internet, Cable TV, and wire-less networks. Because of the resource demanding nature of video streaming applications, maximizing resource utilization in any video streaming system is a key factor to increase the scalability and decrease the cost of the system. Resources to…

  13. Maximizing Resource Utilization in Video Streaming Systems

    Science.gov (United States)

    Alsmirat, Mohammad Abdullah

    2013-01-01

    Video streaming has recently grown dramatically in popularity over the Internet, Cable TV, and wire-less networks. Because of the resource demanding nature of video streaming applications, maximizing resource utilization in any video streaming system is a key factor to increase the scalability and decrease the cost of the system. Resources to…

  14. Streaming Video--The Wave of the Video Future!

    Science.gov (United States)

    Brown, Laura

    2004-01-01

    Videos and DVDs give the teachers more flexibility than slide projectors, filmstrips, and 16mm films but teachers and students are excited about a new technology called streaming. Streaming allows the educators to view videos on demand via the Internet, which works through the transfer of digital media like video, and voice data that is received…

  15. Streaming Video--The Wave of the Video Future!

    Science.gov (United States)

    Brown, Laura

    2004-01-01

    Videos and DVDs give the teachers more flexibility than slide projectors, filmstrips, and 16mm films but teachers and students are excited about a new technology called streaming. Streaming allows the educators to view videos on demand via the Internet, which works through the transfer of digital media like video, and voice data that is received…

  16. Better Video - Streaming Lessons among Palestinian Teachers

    OpenAIRE

    Ali H. AbuSaada; Soon Fook Fong

    2013-01-01

    This study aimed to investigate the effects of redundant information in video streaming of ICDL course for Palestinian trainee-teachers. Two modes of video streaming were used, namely video and narration (VN) mode, and video and narration cum text (VTN) mode of ICDL course. The sample consisted of 203 trainee-teachers in the National Institute for Training (NIT) in Gaza. The results showed that redundancy in the VTN mode increases cognitive overload and split attentions; hence inhibiting the ...

  17. Web Audio/Video Streaming Tool

    Science.gov (United States)

    Guruvadoo, Eranna K.

    2003-01-01

    In order to promote NASA-wide educational outreach program to educate and inform the public of space exploration, NASA, at Kennedy Space Center, is seeking efficient ways to add more contents to the web by streaming audio/video files. This project proposes a high level overview of a framework for the creation, management, and scheduling of audio/video assets over the web. To support short-term goals, the prototype of a web-based tool is designed and demonstrated to automate the process of streaming audio/video files. The tool provides web-enabled users interfaces to manage video assets, create publishable schedules of video assets for streaming, and schedule the streaming events. These operations are performed on user-defined and system-derived metadata of audio/video assets stored in a relational database while the assets reside on separate repository. The prototype tool is designed using ColdFusion 5.0.

  18. Network Characteristics of Video Streaming Traffic

    CERN Document Server

    Rao, Ashwin; Barakat, Chadi; Legout, Arnaud; Towsley, Don; Dabbous, Walid

    2011-01-01

    Video streaming represents a large fraction of Internet traffic. Surprisingly, little is known about the network characteristics of this traffic. In this paper, we study the network characteristics of the two most popular video streaming services, Netflix and YouTube. We show that the streaming strategies vary with the type of the application (Web browser or native mobile application), and the type of container (Silverlight, Flash, or HTML5) used for video streaming. In particular, we identify three different streaming strategies that produce traffic patterns from non-ack clocked ON-OFF cycles to bulk TCP transfer. We then present an analytical model to study the potential impact of these streaming strategies on the aggregate traffic and make recommendations accordingly.

  19. Better Video - Streaming Lessons among Palestinian Teachers

    Directory of Open Access Journals (Sweden)

    Ali H. AbuSaada

    2013-03-01

    Full Text Available This study aimed to investigate the effects of redundant information in video streaming of ICDL course for Palestinian trainee-teachers. Two modes of video streaming were used, namely video and narration (VN mode, and video and narration cum text (VTN mode of ICDL course. The sample consisted of 203 trainee-teachers in the National Institute for Training (NIT in Gaza. The results showed that redundancy in the VTN mode increases cognitive overload and split attentions; hence inhibiting the learning process. The Findings showed that trainee-teachers using the VN mode performed significantly better in post-test scores than counterparts in the VTN modes.

  20. Real-Time QoS-Aware Video Streaming: A Comparative and Experimental Study

    Directory of Open Access Journals (Sweden)

    Basem Al-Madani

    2014-01-01

    Full Text Available Due to its flexibility, scalability, real-time, and rich QoS features, Data Distribution Service (DDS middleware provides seamless integration with high-performance, real-time, and mission-critical networks. Unlike traditional client-server communication models, DDS is based on the publish/subscribe communication model. DDS improves video streaming quality through its efficient and high-performance data delivery mechanism. This paper studies and investigates how DDS is suitable for streaming real-time full-motion video over a communication network. Experimental studies are conducted to compare video streaming using a the VLC player with the DDS overlay. Our results depict the superiority of DDS in provisioning quality video streams at the cost of low network bandwidth. The results also show that DDS is more scalable and flexible and is a promised technology for video distribution over IP networks where it uses much less bandwidth while maintaining high quality video stream delivery.

  1. Authentication for Propulsion Test Streaming Video Project

    Data.gov (United States)

    National Aeronautics and Space Administration — An application was developed that could enforce two-factor authentication for NASA access to the Propulsion Test Streaming Video System.  To gain access to the...

  2. Hand Recognition in Live-Streaming Video

    OpenAIRE

    Mikhail, Belov

    2011-01-01

    The article describes the algorithmic component of the pattern recognition method for extracting hand patterns from a video stream. Methods removing excess information from frames, localizing fragments with a hand and extracting hand contours to classify them are described.

  3. Cloud-Based Mobile Video Streaming Techniques

    Directory of Open Access Journals (Sweden)

    Saurabh Goel,

    2013-03-01

    Full Text Available Reasoning processing is changing the landscape of the electronic digital multi-media market by movingthe end customers concentrate from possession of video to buying entry to them in the form of on-demanddelivery solutions. At the identical time, the cloud is used to collect possessed video pathway and formway out that assist viewers to find a whole new variety of multi-media. Cellular devices are a key carowner of this change, due to their natural mobilityand exclusively high transmission rate among endcustomers. This document investigates cloud centered video streaming methods particularly from themobile viewpoint. The qualitative part of the research contains explanations of current video developmentmethods, streaming methods and third celebration cloud centered streaming solutions for different mobilewhich shows my realistic work relevant to streamingmethods with RTMP protocols family and solutionsfor iPhone, Android, Smart mobile phones, Window and BalackBerry phones etc.

  4. Temporal Segmentation of MPEG Video Streams

    Directory of Open Access Journals (Sweden)

    Janko Calic

    2002-06-01

    Full Text Available Many algorithms for temporal video partitioning rely on the analysis of uncompressed video features. Since the information relevant to the partitioning process can be extracted directly from the MPEG compressed stream, higher efficiency can be achieved utilizing information from the MPEG compressed domain. This paper introduces a real-time algorithm for scene change detection that analyses the statistics of the macroblock features extracted directly from the MPEG stream. A method for extraction of the continuous frame difference that transforms the 3D video stream into a 1D curve is presented. This transform is then further employed to extract temporal units within the analysed video sequence. Results of computer simulations are reported.

  5. Implementation of Video Streaming in Urban VANETs

    Directory of Open Access Journals (Sweden)

    Selvakanmani Nandakumar

    2012-11-01

    Full Text Available Streaming applications will rapidly develop and contribute a significant amount of traffic in the near future. A problem, scarcely addressed so far, is how to distribute video streaming traffic from one source to all nodes in an urban vehicular network. This problem significantly differs from previous work on broadcast and multicast in ad hoc networks because of the highly dynamic topology of vehicular networks and the strict delay requirements of streaming applications. We present a solution for inter vehicular communications, called Streaming Urban Video (SUV. The advantages of using SUV are: 1 Fully distributed and dynamically adapts to topology changes, and 2 leverages the characteristics of streaming applications to yield a highly efficient, cross-layer solution.

  6. The Development of Attention Skills in Action Video Game Players

    Science.gov (United States)

    Dye, M. W. G.; Green, C. S.; Bavelier, D.

    2009-01-01

    Previous research suggests that action video game play improves attentional resources, allowing gamers to better allocate their attention across both space and time. In order to further characterize the plastic changes resulting from playing these video games, we administered the Attentional Network Test (ANT) to action game players and…

  7. Implementation of Mobile Streaming Media Player Based on BREW

    Institute of Scientific and Technical Information of China (English)

    WANG Zhong-rong; LIU Zhao

    2006-01-01

    Nowadays mobile streaming service through cell phone is becoming the highlight of new value-added mobile services. Based on the present CDMA1x wireless data network and Binary Runtime Environment for Wireless (BREW) platform, adopting compression technologies of H.264 and QCP, a set of streaming media players are designed and implemented, and the principle, structure, key technologies and performance analysis of this system are introduced. This player works well in practice.

  8. Audio Video Compression Stream Synthesis and Implementation

    Institute of Scientific and Technical Information of China (English)

    徐燕凌; 方向忠; 周源华

    2004-01-01

    Multiplex of digital streams is one of the key technologies in audio video communication, and determines audio-video quality. A design scheme for an MPEG2 compliant digital television system including audio-video encoding and multiplexing was implemented. The principles and elements of system layer stream synthesis were analyzed. The key technologies of video and audio PES packetization were discussed, such as stream structure,scheduling matching, audio-video synchronization, data flow and buffering. DSP and FPGA are combined to construct header information and packet structure. The substitution of traditional RAM or PLD results in high operational efficiency and saves memory space. A scheduling algorithm was introduced for PES coding, using the monitor information of PES buffers. DTS is generated by multiplexer to guarantee synchronization. The system is not only simple but also stable, and maintains synchronization constraints of the standard. It supports both analogy and digital audio-video source input, and provides real-time MPEG2 compliant TS/PS output. It has perfect performance and meets the national broadcasting requirements.

  9. The Overview and Appliance of some Streaming Video software solutions

    OpenAIRE

    Qin, Yan

    2010-01-01

    This paper introduces the basic streaming media technology, the streaming media system structure, principles of streaming media technology; streaming media file formats and so on. After that, it discusses the use streaming media in distance education, broadband video on demand, Internet broadcasting, video conferences and a more detailed exposition in streaming media. As the existing technology has been unable to satisfy the increasing needs of the Internet users, the streaming media technol...

  10. Creating a streaming video collection for your library

    CERN Document Server

    Duncan, Cheryl J

    2014-01-01

    Creating a Streaming Video Collection for Your Library covers the main processes associated with streaming video, from licensing to access and evaluation, and will serve as a key reference and source of best practices for libraries adding streaming video titles to their collections.

  11. An Assessment of Streaming Video In Web-based Instruction.

    Science.gov (United States)

    Cofield, Jay L.

    Streaming video used as an augmentation in Web-based instruction was investigated to: (1) determine if demographic characteristics would lead to significantly different beliefs about the use and perceived effectiveness of streaming video, and (2) whether or not there are characteristics of streaming video that would lead to beliefs about the…

  12. meIRL-BC: Predicting Player Positions in Video Games

    NARCIS (Netherlands)

    Becht, I.; Bakkes, S.; Barnes, T.; Bogost, I.

    2014-01-01

    In this paper we demonstrate how behaviour-classification models can improve player position prediction for video game AI. To this end, we propose a novel method named meIRL-BC, which (1) uses maximum-entropy Inverse Reinforcement Learning for the creation of position prediction models [15], and (2)

  13. How musical are music video game players?

    Science.gov (United States)

    Pasinski, Amanda C; Hannon, Erin E; Snyder, Joel S

    2016-10-01

    Numerous studies have shown that formal musical training is associated with sensory, motor, and cognitive advantages in individuals of various ages. However, the nature of the observed differences between musicians and nonmusicians is poorly understood, and little is known about the listening skills of individuals who engage in alternative types of everyday musical activities. Here, we show that people who have frequently played music video games outperform nonmusicians controls on a battery of music perception tests. These findings reveal that enhanced musical aptitude can be found among individuals who play music video games, raising the possibility that music video games could potentially enhance music perception skills in individuals across a broad spectrum of society who are otherwise unable to invest the time and/or money required to learn a musical instrument.

  14. Tracking of Ball and Players in Beach Volleyball Videos

    Science.gov (United States)

    Gomez, Gabriel; Herrera López, Patricia; Link, Daniel; Eskofier, Bjoern

    2014-01-01

    This paper presents methods for the determination of players' positions and contact time points by tracking the players and the ball in beach volleyball videos. Two player tracking methods are compared, a classical particle filter and a rigid grid integral histogram tracker. Due to mutual occlusion of the players and the camera perspective, results are best for the front players, with 74,6% and 82,6% of correctly tracked frames for the particle method and the integral histogram method, respectively. Results suggest an improved robustness against player confusion between different particle sets when tracking with a rigid grid approach. Faster processing and less player confusions make this method superior to the classical particle filter. Two different ball tracking methods are used that detect ball candidates from movement difference images using a background subtraction algorithm. Ball trajectories are estimated and interpolated from parabolic flight equations. The tracking accuracy of the ball is 54,2% for the trajectory growth method and 42,1% for the Hough line detection method. Tracking results of over 90% from the literature could not be confirmed. Ball contact frames were estimated from parabolic trajectory intersection, resulting in 48,9% of correctly estimated ball contact points. PMID:25426936

  15. Violent video game players and non-players differ on facial emotion recognition.

    Science.gov (United States)

    Diaz, Ruth L; Wong, Ulric; Hodgins, David C; Chiu, Carina G; Goghari, Vina M

    2016-01-01

    Violent video game playing has been associated with both positive and negative effects on cognition. We examined whether playing two or more hours of violent video games a day, compared to not playing video games, was associated with a different pattern of recognition of five facial emotions, while controlling for general perceptual and cognitive differences that might also occur. Undergraduate students were categorized as violent video game players (n = 83) or non-gamers (n = 69) and completed a facial recognition task, consisting of an emotion recognition condition and a control condition of gender recognition. Additionally, participants completed questionnaires assessing their video game and media consumption, aggression, and mood. Violent video game players recognized fearful faces both more accurately and quickly and disgusted faces less accurately than non-gamers. Desensitization to violence, constant exposure to fear and anxiety during game playing, and the habituation to unpleasant stimuli, are possible mechanisms that could explain these results. Future research should evaluate the effects of violent video game playing on emotion processing and social cognition more broadly.

  16. Frequent video game players resist perceptual interference.

    Directory of Open Access Journals (Sweden)

    Aaron V Berard

    Full Text Available Playing certain types of video games for a long time can improve a wide range of mental processes, from visual acuity to cognitive control. Frequent gamers have also displayed generalized improvements in perceptual learning. In the Texture Discrimination Task (TDT, a widely used perceptual learning paradigm, participants report the orientation of a target embedded in a field of lines and demonstrate robust over-night improvement. However, changing the orientation of the background lines midway through TDT training interferes with overnight improvements in overall performance on TDT. Interestingly, prior research has suggested that this effect will not occur if a one-hour break is allowed in between the changes. These results have suggested that after training is over, it may take some time for learning to become stabilized and resilient against interference. Here, we tested whether frequent gamers have faster stabilization of perceptual learning compared to non-gamers and examined the effect of daily video game playing on interference of training of TDT with one background orientation on perceptual learning of TDT with a different background orientation. As a result, we found that non-gamers showed overnight performance improvement only on one background orientation, replicating previous results with the interference in TDT. In contrast, frequent gamers demonstrated overnight improvements in performance with both background orientations, suggesting that they are better able to overcome interference in perceptual learning. This resistance to interference suggests that video game playing not only enhances the amplitude and speed of perceptual learning but also leads to faster and/or more robust stabilization of perceptual learning.

  17. Stream Station video server system. Video saba sochi 'Stream station'

    Energy Technology Data Exchange (ETDEWEB)

    1999-03-01

    A video server system Stream Station is developed for delivering moving images to the client on the VOD (video on demand) basis. In this system, video data compressed using the MPEG (Moving Picture Experts Group) technique are stored in a RAID (redundant arrays of independent disks) system, and is outputted as analog video data after expansion in a decoder provided at the output stage. The server system easily realizes a VOD system using the existing in-house cable TV facilities for instance for hotel rooms. The data for this purpose may be either in the MPEG1 or MPEG2 format, pictures may be simultaneously transmitted via as many as 32 channels at the maximum, and the storage holds 256 gigabytes at the maximum. It incorporates a video server architecture developed by Toshiba Corporation, and the data transfer rate from data readout to transmission is totally warranted. (translated by NEDO)

  18. Live HDR video streaming on commodity hardware

    Science.gov (United States)

    McNamee, Joshua; Hatchett, Jonathan; Debattista, Kurt; Chalmers, Alan

    2015-09-01

    High Dynamic Range (HDR) video provides a step change in viewing experience, for example the ability to clearly see the soccer ball when it is kicked from the shadow of the stadium into sunshine. To achieve the full potential of HDR video, so-called true HDR, it is crucial that all the dynamic range that was captured is delivered to the display device and tone mapping is confined only to the display. Furthermore, to ensure widespread uptake of HDR imaging, it should be low cost and available on commodity hardware. This paper describes an end-to-end HDR pipeline for capturing, encoding and streaming high-definition HDR video in real-time using off-the-shelf components. All the lighting that is captured by HDR-enabled consumer cameras is delivered via the pipeline to any display, including HDR displays and even mobile devices with minimum latency. The system thus provides an integrated HDR video pipeline that includes everything from capture to post-production, archival and storage, compression, transmission, and display.

  19. GPRS Video Streaming Surveillance System GVSS

    CERN Document Server

    Pushpavathi, T P; Kumar, N R Shashi

    2010-01-01

    Future security measures will create comfortable living environments that are embedded with a wide range of intelligent functionalities including home computing, entertainment, health care and security. These place stringent requirements on the home networking architecture which integrates various existing technologies for monitoring and control for future high security needs. This paper discusses the design and implementation of a gvss gprs Video Streaming Surveillance System system, which integrates various existing technologies for providing security for smart home environments. This system provides security for office, home and other buildings where high security is required.This allows the mobile user to track the activities from a particular location. The system will send snapshots of the video and stores them in different formats. It is also possible to display the time with the image when it was captured in the gprs enabled mobiles. This system is implemented using J2me Technology

  20. Packet Selection and Scheduling for Multipath Video Streaming

    OpenAIRE

    Jurca, Dan; Frossard, Pascal

    2004-01-01

    This paper addresses the problem of choosing the best streaming policy for distortion optimal multipath video delivery, under delay constraints. The streaming policy consists in a joint selection of the video packets to be transmitted, as well as their sending time, and the transmission path. A simple streaming model is introduced, which takes into account the video packet importance, and the dependencies among packets, and allows to compute the quality perceived by the receiver, as a functio...

  1. Software for simulating dichromatic perception of video streams

    OpenAIRE

    2013-01-01

    We have designed a configurable stand-alone Matlab-based software to simulate dichromatic perception of video streams. The algorithm used is an extension for video streams of the “corresponding pair algorithm” by Capilla and coworkers for simulation of dichromatic perception of images. The software allows the user to upload a video sequence and to process it using different dichromatic color vision models and viewing conditions. The output video may be generated in different spatial and tempo...

  2. Advanced real-time manipulation of video streams

    CERN Document Server

    Herling, Jan

    2014-01-01

    Diminished Reality is a new fascinating technology that removes real-world content from live video streams. This sensational live video manipulation actually removes real objects and generates a coherent video stream in real-time. Viewers cannot detect modified content. Existing approaches are restricted to moving objects and static or almost static cameras and do not allow real-time manipulation of video content. Jan Herling presents a new and innovative approach for real-time object removal with arbitrary camera movements.

  3. Video streaming: implementation and evaluation in an undergraduate nursing program.

    Science.gov (United States)

    Bennett, Paul N; Glover, Pauline

    2008-02-01

    Video streaming technology enables video content, held on the web sites, to be streamed via the web. We report the implementation and evaluation of video streaming in an undergraduate nursing program in a metropolitan university in Australia. Students (n=703) were emailed a survey with a 15% response rate. We found that 91% (n=74) of respondents stated that video streaming assisted their learning. Forty-six percent(n=50) of students had difficulty accessing video streaming (particularly at the beginning of the study period). Over a 97-day period there were 8440 "hits" to the site from 1039 different internet protocol (IP) addresses. There were 4475 video streaming sessions undertaken by users. Video streaming was used for reviewing previously attended lectures (52%, n=56), examination preparation (34%, n=37), viewing missed lectures (27%, n=29) and class preparation (9%, n=10). Our experience with the introduction of video streaming has met with general enthusiasm from both students and teaching staff. Video streaming has particular relevance for rural students.

  4. Object tracking using multiple camera video streams

    Science.gov (United States)

    Mehrubeoglu, Mehrube; Rojas, Diego; McLauchlan, Lifford

    2010-05-01

    Two synchronized cameras are utilized to obtain independent video streams to detect moving objects from two different viewing angles. The video frames are directly correlated in time. Moving objects in image frames from the two cameras are identified and tagged for tracking. One advantage of such a system involves overcoming effects of occlusions that could result in an object in partial or full view in one camera, when the same object is fully visible in another camera. Object registration is achieved by determining the location of common features in the moving object across simultaneous frames. Perspective differences are adjusted. Combining information from images from multiple cameras increases robustness of the tracking process. Motion tracking is achieved by determining anomalies caused by the objects' movement across frames in time in each and the combined video information. The path of each object is determined heuristically. Accuracy of detection is dependent on the speed of the object as well as variations in direction of motion. Fast cameras increase accuracy but limit the speed and complexity of the algorithm. Such an imaging system has applications in traffic analysis, surveillance and security, as well as object modeling from multi-view images. The system can easily be expanded by increasing the number of cameras such that there is an overlap between the scenes from at least two cameras in proximity. An object can then be tracked long distances or across multiple cameras continuously, applicable, for example, in wireless sensor networks for surveillance or navigation.

  5. A New Design of Video Streaming Capture and Transmission System

    Directory of Open Access Journals (Sweden)

    Xingyu Geng

    2014-10-01

    Full Text Available Aiming to solve some existing problems such as low video streaming rate, high cost and complex set-up, a new video streaming capture and transmission system based on servfox is proposed. This system uses servfox to invoke V4L APIs to capture video streaming in Linux operating system, and then transmits the data to a remote monitoring client through Internet which can display the video streaming. Remote client can be either a software or a web browser. The experimental results show that the image captured by this system is high-quality and the streaming rate is high. At the same time, the system possesses high reliability and low cost. Compared with existing methods, this system can be widely used in the process of video streaming capture and transmission

  6. Illusory control, gambling, and video gaming: an investigation of regular gamblers and video game players.

    Science.gov (United States)

    King, Daniel L; Ejova, Anastasia; Delfabbro, Paul H

    2012-09-01

    There is a paucity of empirical research examining the possible association between gambling and video game play. In two studies, we examined the association between video game playing, erroneous gambling cognitions, and risky gambling behaviour. One hundred and fifteen participants, including 65 electronic gambling machine (EGM) players and 50 regular video game players, were administered a questionnaire that examined video game play, gambling involvement, problem gambling, and beliefs about gambling. We then assessed each groups' performance on a computerised gambling task that involved real money. A post-game survey examined perceptions of the skill and chance involved in the gambling task. The results showed that video game playing itself was not significantly associated with gambling involvement or problem gambling status. However, among those persons who both gambled and played video games, video game playing was uniquely and significantly positively associated with the perception of direct control over chance-based gambling events. Further research is needed to better understand the nature of this association, as it may assist in understanding the impact of emerging digital gambling technologies.

  7. Scalable Video Streaming in Wireless Mesh Networks for Education

    Science.gov (United States)

    Liu, Yan; Wang, Xinheng; Zhao, Liqiang

    2011-01-01

    In this paper, a video streaming system for education based on a wireless mesh network is proposed. A wireless mesh network is a self-organizing, self-managing and reliable intelligent network, which allows educators to deploy a network quickly. Video streaming plays an important role in this system for multimedia data transmission. This new…

  8. Scalable Video Streaming in Wireless Mesh Networks for Education

    Science.gov (United States)

    Liu, Yan; Wang, Xinheng; Zhao, Liqiang

    2011-01-01

    In this paper, a video streaming system for education based on a wireless mesh network is proposed. A wireless mesh network is a self-organizing, self-managing and reliable intelligent network, which allows educators to deploy a network quickly. Video streaming plays an important role in this system for multimedia data transmission. This new…

  9. Perceived Coding Distortion Assessment for Streaming Video

    Directory of Open Access Journals (Sweden)

    Fuzheng Yang

    2010-04-01

    Full Text Available For applications involving video streaming, full decoding is usually not acceptable for quality assessment. To address the inherent challenges, an efficient method for coding distortion assessment is proposed in this paper. Building on empirical analysis, the proposed method employs a linear model to assess the coding distortion using the quantization scale. Furthermore, the characteristics of the human visual system are exploited by taking into account the spatial and temporal masking. To estimate the required spatial and temporal complexities in absence of sufficient information, a rate-distortion model is theoretically derived to formulate their relationship with the coding bit-rate. Extensive experimental results have demonstrated the effectiveness of the proposed method for quality assessment with respect to perceived coding distortion.

  10. Improved control of exogenous attention in action video game players

    Directory of Open Access Journals (Sweden)

    Matthew S Cain

    2014-02-01

    Full Text Available Action video game players have demonstrated a number of attentional advantages over non-players. Here, we propose that many of those benefits might be underpinned by improved control over exogenous (i.e., stimulus-driven attention. To test this we used an anti-cuing task, in which a sudden-onset cue indicated that the target would likely appear in a separate location on the opposite side of the fixation point. When the time between the cue onset and the target onset was short (40 ms, non-players (nVGPs showed a typical exogenous attention effect. Their response times were faster to targets presented at the cued (but less probable location compared with the opposite (more probable location. Video game players (VGPs, however, were less likely to have their attention drawn to the location of the cue. When the onset asynchrony was long (600 ms, VGPs and nVGPs were equally able to endogenously shift their attention to the likely (opposite target location. In order to rule out processing-speed differences as an explanation for this result, we also tested VGPs and nVGPs on an attentional blink task. In a version of the attentional blink task that minimized demands on task switching and iconic memory, VGPs and nVGPs did not differ in second target identification performance (i.e., VGPs had the same magnitude of attentional blink as nVGPs, suggesting that the anti-cuing results were due to flexible control over exogenous attention rather than to more general speed-of-processing differences.

  11. Optimal Rate Allocation Algorithm for Multiple Source Video Streaming

    Institute of Scientific and Technical Information of China (English)

    戢彦泓; 郭常杰; 钟玉琢; 孙立峰

    2004-01-01

    Video streaming is one of the most important applications used in the best-effort Internet.This paper presents a new scheme for multiple source video streaming in which the traditional fine granular scalable coding was rebuilt into a multiple sub-streams based transmission model.A peak signal to noise ratio based stream rate allocation algorithm was then developed based on the transmission model.In tests,the algorithm performance is about 1 dB higher than that of a uniform rate allocation algorithm.Therefore,this scheme can overcome bottlenecks along a single link and smooth jitter to achieve high quality and stable video.

  12. Fast compressed domain motion detection in H.264 video streams for video surveillance applications

    DEFF Research Database (Denmark)

    Szczerba, Krzysztof; Forchhammer, Søren; Støttrup-Andersen, Jesper;

    2009-01-01

    This paper presents a novel approach to fast motion detection in H.264/MPEG-4 advanced video coding (AVC) compressed video streams for IP video surveillance systems. The goal is to develop algorithms which may be useful in a real-life industrial perspective by facilitating the processing of large...... numbers of video streams on a single server. The focus of the work is on using the information in coded video streams to reduce the computational complexity and memory requirements, which translates into reduced hardware requirements and costs. The devised algorithm detects and segments activity based...... on motion vectors embedded in the video stream without requiring a full decoding and reconstruction of video frames. To improve the robustness to noise, a confidence measure based on temporal and spatial clues is introduced to increase the probability of correct detection. The algorithm was tested on indoor...

  13. P2P Video Streaming Strategies based on Scalable Video Coding

    Directory of Open Access Journals (Sweden)

    F.A. López-Fuentes

    2015-02-01

    Full Text Available Video streaming over the Internet has gained significant popularity during the last years, and the academy and industry have realized a great research effort in this direction. In this scenario, scalable video coding (SVC has emerged as an important video standard to provide more functionality to video transmission and storage applications. This paper proposes and evaluates two strategies based on scalable video coding for P2P video streaming services. In the first strategy, SVC is used to offer differentiated quality video to peers with heterogeneous capacities. The second strategy uses SVC to reach a homogeneous video quality between different videos from different sources. The obtained results show that our proposed strategies enable a system to improve its performance and introduce benefits such as differentiated quality of video for clients with heterogeneous capacities and variable network conditions.

  14. Forecasting the Market for New Communication Technology: The Home Video Player Experience.

    Science.gov (United States)

    Klopfenstein, Bruce C.

    This paper describes a critical study of the available forecasts and forecasting studies for the home video player market over a 15-year period which was undertaken to discover why so many forecasts were wrong about consumer adoption of home videocassette players and videodisk players, the reasons for these errors, and ways in which this knowledge…

  15. Effects of Modality Principle in Tutorial Video Streaming

    OpenAIRE

    Ali H. AbuSaada; Lily Pei Lin Lee; Soon Fook Fong

    2013-01-01

    This study aimed to investigate the effects of Modality Principle in video streaming of ICDL course for trainee-teachers. Two modes of video streaming were used, namely video and narration (VN) mode, and video and text (VT) mode of ICDL course. The sample consisted of 202 trainee-teachers in the National Institute for Training (NIT) in Gaza. The results showed that the learners using the VN mode attained significant better achievement than the learners using the VT mode. The learners using th...

  16. The Use of Smart Glasses for Surgical Video Streaming.

    Science.gov (United States)

    Hiranaka, Takafumi; Nakanishi, Yuta; Fujishiro, Takaaki; Hida, Yuichi; Tsubosaka, Masanori; Shibata, Yosaku; Okimura, Kenjiro; Uemoto, Harunobu

    2017-04-01

    Observation of surgical procedures performed by experts is extremely important for acquisition and improvement of surgical skills. Smart glasses are small computers, which comprise a head-mounted monitor and video camera, and can be connected to the internet. They can be used for remote observation of surgeries by video streaming. Although Google Glass is the most commonly used smart glasses for medical purposes, it is still unavailable commercially and has some limitations. This article reports the use of a different type of smart glasses, InfoLinker, for surgical video streaming. InfoLinker has been commercially available in Japan for industrial purposes for more than 2 years. It is connected to a video server via wireless internet directly, and streaming video can be seen anywhere an internet connection is available. We have attempted live video streaming of knee arthroplasty operations that were viewed at several different locations, including foreign countries, on a common web browser. Although the quality of video images depended on the resolution and dynamic range of the video camera, speed of internet connection, and the wearer's attention to minimize image shaking, video streaming could be easily performed throughout the procedure. The wearer could confirm the quality of the video as the video was being shot by the head-mounted display. The time and cost for observation of surgical procedures can be reduced by InfoLinker, and further improvement of hardware as well as the wearer's video shooting technique is expected. We believe that this can be used in other medical settings.

  17. Effective Quality-of-Service Renegotiating Schemes for Streaming Video

    Directory of Open Access Journals (Sweden)

    Song Hwangjun

    2004-01-01

    Full Text Available This paper presents effective quality-of-service renegotiating schemes for streaming video. The conventional network supporting quality of service generally allows a negotiation at a call setup. However, it is not efficient for the video application since the compressed video traffic is statistically nonstationary. Thus, we consider the network supporting quality-of-service renegotiations during the data transmission and study effective quality-of-service renegotiating schemes for streaming video. The token bucket model, whose parameters are token filling rate and token bucket size, is adopted for the video traffic model. The renegotiating time instants and the parameters are determined by analyzing the statistical information of compressed video traffic. In this paper, two renegotiating approaches, that is, fixed renegotiating interval case and variable renegotiating interval case, are examined. Finally, the experimental results are provided to show the performance of the proposed schemes.

  18. Can Viral Videos Help Beaver Restore Streams?

    Science.gov (United States)

    Castro, J. M.; Pollock, M. M.; Lewallen, G.; Jordan, C.; Woodruff, K.

    2015-12-01

    Have you watched YouTube lately? Did you notice the plethora of cute animal videos? Researchers, including members of our Beaver Restoration Research team, have been studying the restoration potential of beaver for decades, yet in the past few years, beaver have gained broad acclaim and some much deserved credit for restoration of aquatic systems in North America. Is it because people can now see these charismatic critters in action from the comfort of their laptops? While the newly released Beaver Restoration Guidebook attempts to answer many questions, sadly, this is not one of them. We do, however, address the use of beaver (Castor canadensis) in stream, wetland, and floodplain restoration and discuss the many positive effects of beaver on fluvial ecosystems. Our team, composed of researchers from NOAA National Marine Fisheries Service, US Fish and Wildlife Service, US Forest Service, and Portland State University, has developed a scientifically rigorous, yet accessible, practitioner's guide that provides a synthesis of the best available science for using beaver to improve ecosystem functions. Divided into two broad sections -- Beaver Ecology and Beaver Restoration and Management -- the guidebook focuses on the many ways in which beaver improve habitat, primarily through the construction of dams that impound water and retain sediment. In Beaver Ecology, we open with a discussion of the general effects that beaver dams have on physical and biological processes, and we close with "Frequently Asked Questions" and "Myth Busters". In Restoration and Management, we discuss common emerging restoration techniques and methods for mitigating unwanted beaver effects, followed by case studies from pioneering practitioners who have used many of these beaver restoration techniques in the field. The lessons they have learned will help guide future restoration efforts. We have also included a comprehensive beaver ecology library of over 1400 references from scientific journals

  19. Factors that Influence Learning Satisfaction Delivered by Video Streaming Technology

    Science.gov (United States)

    Keenan, Daniel Stephen

    2010-01-01

    In 2005, over 100,000 e-Learning courses were offered in over half of all U.S. postsecondary education institutions with nearly 90% of all community colleges and four year institutions offering online education. Streaming video is commonplace across the internet offering seamless video and sound anywhere connectivity is available effectively…

  20. Streaming Video to Enhance Students' Reflection in Dance Education

    Science.gov (United States)

    Leijen, Ali; Lam, Ineke; Wildschut, Liesbeth; Simons, P. Robert-Jan; Admiraal, Wilfried

    2009-01-01

    This paper presents an evaluation case study that describes the experiences of 15 students and 2 teachers using a video-based learning environment, DiViDU, to facilitate students' daily reflection activities in a composition course and a ballet course. To support dance students' reflection processes streaming video was applied as follows: video…

  1. Factors that Influence Learning Satisfaction Delivered by Video Streaming Technology

    Science.gov (United States)

    Keenan, Daniel Stephen

    2010-01-01

    In 2005, over 100,000 e-Learning courses were offered in over half of all U.S. postsecondary education institutions with nearly 90% of all community colleges and four year institutions offering online education. Streaming video is commonplace across the internet offering seamless video and sound anywhere connectivity is available effectively…

  2. Streaming Video to Enhance Students' Reflection in Dance Education

    Science.gov (United States)

    Leijen, Ali; Lam, Ineke; Wildschut, Liesbeth; Simons, P. Robert-Jan; Admiraal, Wilfried

    2009-01-01

    This paper presents an evaluation case study that describes the experiences of 15 students and 2 teachers using a video-based learning environment, DiViDU, to facilitate students' daily reflection activities in a composition course and a ballet course. To support dance students' reflection processes streaming video was applied as follows: video…

  3. The Gambling Preferences and Behaviors of a Community Sample of Australian Regular Video Game Players.

    Science.gov (United States)

    Forrest, Cameron J; King, Daniel L; Delfabbro, Paul H

    2016-06-01

    Research has noted many similarities between video gaming and gambling activities. It has been suggested that video game players may also be attracted to gambling, although there is limited research on this possibility. The present study examined concurrent video gaming and gambling habits in a sample of regular video game players in Australia (N = 485, 84 % male, M age = 25.8). Gambling involvement was found to be a generally unpopular activity among regular video game players. No significant association between frequency of video game play and frequency of gambling was found. Although significant correlations between gaming 'addiction' scores and gambling frequency were identified, age was the only significant predictor of gambling when controlling for all remaining variables. These findings are critically discussed in the context of past research, and future research directions concerning the link between video gaming and gambling are proposed.

  4. Crowdsourcing based subjective quality assessment of adaptive video streaming

    DEFF Research Database (Denmark)

    Shahid, M.; Søgaard, Jacob; Pokhrel, J.

    2014-01-01

    humans are considered to be the most valid method of the as- sessment of QoE. Besides lab-based subjective experiments, crowdsourcing based subjective assessment of video quality is gaining popularity as an alternative method. This paper presents insights into a study that investigates perceptual pref......- erences of various adaptive video streaming scenarios through crowdsourcing based subjective quality assessment.......In order to cater for user’s quality of experience (QoE) re- quirements, HTTP adaptive streaming (HAS) based solutions of video services have become popular recently. User QoE feedback can be instrumental in improving the capabilities of such services. Perceptual quality experiments that involve...

  5. Video streaming in nursing education: bringing life to online education.

    Science.gov (United States)

    Smith-Stoner, Marilyn; Willer, Ann

    2003-01-01

    Distance education is a standard form of instruction for many colleges of nursing. Web-based course and program content has been delivered primarily through text-based presentations such as PowerPoint slides and Web search activities. However, the rapid pace of technological innovation is making available more sophisticated forms of delivery such as video streaming. High-quality video streams, created at the instructor's desktop or in basic recording studios, can be produced that build on PowerPoint or create new media for use on the Web. The technology required to design, produce, and upload short video-streamed course content objects to the Internet is described. The preparation of materials, suggested production guidelines, and examples of information presented via desktop video methods are presented.

  6. On optimal receiver buffer size in adaptive Internet video streaming

    Institute of Scientific and Technical Information of China (English)

    OZBEK Nukhet; TUNALI E. Turhan

    2006-01-01

    The effect of receiver buffer size on perceived video quality of an Internet video streamer application was examined in this work. Several network conditions and several versions of the application are used to gain understanding of the response to varying buffer sizes. Among these conditions local area versus wide area, bandwidth estimation based versus non-bandwidth estimation based cases are examined in detail. A total of 1000 min of video is streamed over Intemet and statistics are collected. It was observed that when bandwidth estimation is possible, choosing larger buffer size for higher available bandwidth yields quality increase in perceived video.

  7. Evaluation of packet loss impairment on streaming video

    Institute of Scientific and Technical Information of China (English)

    RUI Hua-xia; LI Chong-rong; QIU Sheng-ke

    2006-01-01

    Video compression technologies are essential in video streaming application because they could save a great amount of network resources. However compressed videos are also extremely sensitive to packet loss which is inevitable in today's best effort IP network. Therefore we think accurate evaluation of packet loss impairment on compressed video is very important. In this work, we develop an analytic model to describe these impairments without the reference of the original video (NR) and propose an impairment metric based on the model, which takes into account both impairment length and impairment strength. To evaluate an impaired frame or video, we design a detection and evaluation algorithm (DE algorithm) to compute the above metric value. The DE algorithm has low computational complexity and is currently being implemented in the real-time monitoring module of our HDTV over IP system. The impairment metric and DE algorithm could also be used in adaptive system or be used to compare diffeient error concealment strategies.

  8. Medical Students' Perceptions of Video-Linked Lectures and Video-Streaming

    Science.gov (United States)

    Wang, RuoLan; Mattick, Karen; Dunne, Elisabeth

    2010-01-01

    Video-linked lectures allow healthcare students across multiple sites, and between university and hospital bases, to come together for the purposes of shared teaching. Recording and streaming video-linked lectures allows students to view them at a later date and provides an additional resource to support student learning. As part of a UK Higher…

  9. Effects of Modality Principle in Tutorial Video Streaming

    Directory of Open Access Journals (Sweden)

    Ali H. AbuSaada

    2013-05-01

    Full Text Available This study aimed to investigate the effects of Modality Principle in video streaming of ICDL course for trainee-teachers. Two modes of video streaming were used, namely video and narration (VN mode, and video and text (VT mode of ICDL course. The sample consisted of 202 trainee-teachers in the National Institute for Training (NIT in Gaza. The results showed that the learners using the VN mode attained significant better achievement than the learners using the VT mode. The learners using the VN mode are learn better and more deeply than the VT mode. The presented information in both visual and auditory modes imposes lesser cognitive demands on learners’ without overloading working memory. Thus, more working memory capacity remains available for information processing and improve the learning outcomes.

  10. Adaptive live multicast video streaming of SVC with UEP FEC

    Science.gov (United States)

    Lev, Avram; Lasry, Amir; Loants, Maoz; Hadar, Ofer

    2014-09-01

    Ideally, video streaming systems should provide the best quality video a user's device can handle without compromising on downloading speed. In this article, an improved video transmission system is presented which dynamically enhances the video quality based on a user's current network state and repairs errors from data lost in the video transmission. The system incorporates three main components: Scalable Video Coding (SVC) with three layers, multicast based on Receiver Layered Multicast (RLM) and an UnEqual Forward Error Correction (FEC) algorithm. The SVC provides an efficient method for providing different levels of video quality, stored as enhancement layers. In the presented system, a proportional-integral-derivative (PID) controller was implemented to dynamically adjust the video quality, adding or subtracting quality layers as appropriate. In addition, an FEC algorithm was added to compensate for data lost in transmission. A two dimensional FEC was used. The FEC algorithm came from the Pro MPEG code of practice #3 release 2. Several bit errors scenarios were tested (step function, cosine wave) with different bandwidth size and error values were simulated. The suggested scheme which includes SVC video encoding with 3 layers over IP Multicast with Unequal FEC algorithm was investigated under different channel conditions, variable bandwidths and different bit error rates. The results indicate improvement of the video quality in terms of PSNR over previous transmission schemes.

  11. Video Streaming for Creative Writing at International Elementary School

    Directory of Open Access Journals (Sweden)

    Deni Darmawan

    2013-02-01

    Full Text Available This study aims at overcoming difficulty in learning language, both in Indonesian Language and English at international elementary school, especially in creative writing. Creative writing as part of human activity is creativity with language medium as prose (narrative, description, poem (old, new and modern, as well as drama (dialogue, role play, and sosio drama. Specific target to be achieved is the design of Video Streaming for all kinds of creative writing in the language of Indonesian and English. This investigation is a continuation of the previos investigation that has managed to make a video leaning in English for Math and Science as integrated learning to early class at international elementary school. The method used follow the principles of developmental reasearch. The firts stage is script writing video streaming through brainstorming with teachers, lecturers, teams of investigators Indonesia (UPI and Malaysia (USM. The second stage manuscript, making finalization Video Streaming, make the Web, media experts and creative writing material team investigators. The third stage, testing the Video Streaming, Web and dissemination of results into all the international elementary school in Indonesia and Malaysia.

  12. Case study: student perceptions of video streaming nursing class sessions.

    Science.gov (United States)

    Wall Parilo, Denise M; Parsh, Bridget

    2014-03-01

    Due to space constraints, students in their pediatric and obstetrical nursing courses received lecture in two formats: live lecture and video-streamed lecture. Live lecture is the traditional classroom format of live, in-person lecture without recording archives, whereas video streaming is live (synchronous) online lecture, also recorded for digital archive (asynchronous viewing). At the end of the semester, students (N = 53) responded to a survey about what they liked about both methods of instruction. Results reveal strengths of both methods and suggest ways to make both methods more effective.

  13. Objective video presentation QoE predictor for smart adaptive video streaming

    Science.gov (United States)

    Wang, Zhou; Zeng, Kai; Rehman, Abdul; Yeganeh, Hojatollah; Wang, Shiqi

    2015-09-01

    How to deliver videos to consumers over the network for optimal quality-of-experience (QoE) has been the central goal of modern video delivery services. Surprisingly, regardless of the large volume of videos being delivered everyday through various systems attempting to improve visual QoE, the actual QoE of end consumers is not properly assessed, not to say using QoE as the key factor in making critical decisions at the video hosting, network and receiving sites. Real-world video streaming systems typically use bitrate as the main video presentation quality indicator, but using the same bitrate to encode different video content could result in drastically different visual QoE, which is further affected by the display device and viewing condition of each individual consumer who receives the video. To correct this, we have to put QoE back to the driver's seat and redesign the video delivery systems. To achieve this goal, a major challenge is to find an objective video presentation QoE predictor that is accurate, fast, easy-to-use, display device adaptive, and provides meaningful QoE predictions across resolution and content. We propose to use the newly developed SSIMplus index (https://ece.uwaterloo.ca/~z70wang/research/ssimplus/) for this role. We demonstrate that based on SSIMplus, one can develop a smart adaptive video streaming strategy that leads to much smoother visual QoE impossible to achieve using existing adaptive bitrate video streaming approaches. Furthermore, SSIMplus finds many more applications, in live and file-based quality monitoring, in benchmarking video encoders and transcoders, and in guiding network resource allocations.

  14. Error and Congestion Resilient Video Streaming over Broadband Wireless

    Directory of Open Access Journals (Sweden)

    Laith Al-Jobouri

    2015-04-01

    Full Text Available In this paper, error resilience is achieved by adaptive, application-layer rateless channel coding, which is used to protect H.264/Advanced Video Coding (AVC codec data-partitioned videos. A packetization strategy is an effective tool to control error rates and, in the paper, source-coded data partitioning serves to allocate smaller packets to more important compressed video data. The scheme for doing this is applied to real-time streaming across a broadband wireless link. The advantages of rateless code rate adaptivity are then demonstrated in the paper. Because the data partitions of a video slice are each assigned to different network packets, in congestion-prone wireless networks the increased number of packets per slice and their size disparity may increase the packet loss rate from buffer overflows. As a form of congestion resilience, this paper recommends packet-size dependent scheduling as a relatively simple way of alleviating the buffer-overflow problem arising from data-partitioned packets. The paper also contributes an analysis of data partitioning and packet sizes as a prelude to considering scheduling regimes. The combination of adaptive channel coding and prioritized packetization for error resilience with packet-size dependent packet scheduling results in a robust streaming scheme specialized for broadband wireless and real-time streaming applications such as video conferencing, video telephony, and telemedicine.

  15. Medical students' perceptions of video-linked lectures and video-streaming

    Directory of Open Access Journals (Sweden)

    Karen Mattick

    2010-12-01

    Full Text Available Video-linked lectures allow healthcare students across multiple sites, and between university and hospital bases, to come together for the purposes of shared teaching. Recording and streaming video-linked lectures allows students to view them at a later date and provides an additional resource to support student learning. As part of a UK Higher Education Academy-funded Pathfinder project, this study explored medical students' perceptions of video-linked lectures and video-streaming, and their impact on learning. The methodology involved semi-structured interviews with 20 undergraduate medical students across four sites and five year groups. Several key themes emerged from the analysis. Students generally preferred live lectures at the home site and saw interaction between sites as a major challenge. Students reported that their attendance at live lectures was not affected by the availability of streamed lectures and tended to be influenced more by the topic and speaker than the technical arrangements. These findings will inform other educators interested in employing similar video technologies in their teaching.Keywords: video-linked lecture; video-streaming; student perceptions; decisionmaking; cross-campus teaching.

  16. Modeling Stability and Bitrate of Network-Assisted HTTP Adaptive Streaming Players

    NARCIS (Netherlands)

    Kleinrouweler, J.W.M.; Cabrero Barros, S.; Mei, R.D. van der; Cesar Garcia, P.S.

    2015-01-01

    Viewers using HTTP Adaptive Streaming (HAS) without sufficient bandwidth undergo frequent quality switches that hinder their watching experience. This situation, known as instability, is produced when HAS players are unable to accurately estimate the available bandwidth. Moreover, when several playe

  17. Notions of Video Game Addiction and Their Relation to Self-Reported Addiction among Players of World of Warcraft

    Science.gov (United States)

    Oggins, Jean; Sammis, Jeffrey

    2012-01-01

    In this study, 438 players of the online video game, World of Warcraft, completed a survey about video game addiction and answered an open-ended question about behaviors they considered characteristic of video game addiction. Responses were coded and correlated with players' self-reports of being addicted to games and scores on a modified video…

  18. Notions of Video Game Addiction and Their Relation to Self-Reported Addiction among Players of World of Warcraft

    Science.gov (United States)

    Oggins, Jean; Sammis, Jeffrey

    2012-01-01

    In this study, 438 players of the online video game, World of Warcraft, completed a survey about video game addiction and answered an open-ended question about behaviors they considered characteristic of video game addiction. Responses were coded and correlated with players' self-reports of being addicted to games and scores on a modified video…

  19. The Psychological Study of Video Game Players: Methodological Challenges and Practical Advice

    Science.gov (United States)

    King, Daniel; Delfabbro, Paul; Griffiths, Mark

    2009-01-01

    Video game playing has received increased academic interest over the last few decades, particularly with regard to the psychological understanding of addiction. Based on the many studies carried out by the authors, this paper summarises some of the methodological challenges which may arise when studying video game players, including obstacles…

  20. Junior football players' classification of runners as their teammates from 400-msec. video clips.

    Science.gov (United States)

    Steel, Kylie A; Adams, Roger D; Canning, Colleen G

    2008-08-01

    It was hypothesized that a specialized gait recognition skill enables humans to distinguish the gait of familiar from unfamiliar individuals, and that this may have relevance in team sports. Runners seen for less than half a second can be classified as teammates or not by adult players, so it may be asked whether this skill would also be demonstrated by young team players. In the current study, junior football players (M age = 10.0 yr., SD = 0.8, N = 13) viewed 400-msec. video clips of runners sprinting past a fixed forward facing digital video camera and similarly showed teammate recognition scores significantly above chance. Given the variation among the junior players in this skill, it seems possible for researchers to assess whether improvement can be obtained with structured training for young team players, where running teammates are seen in peripheral vision during training drills.

  1. Adaptive Error Resilience for Video Streaming

    Directory of Open Access Journals (Sweden)

    Lakshmi R. Siruvuri

    2009-01-01

    Full Text Available Compressed video sequences are vulnerable to channel errors, to the extent that minor errors and/or small losses can result in substantial degradation. Thus, protecting compressed data against channel errors is imperative. The use of channel coding schemes can be effective in reducing the impact of channel errors, although this requires that extra parity bits to be transmitted, thus utilizing more bandwidth. However, this can be ameliorated if the transmitter can tailor the parity data rate based on its knowledge regarding current channel conditions. This can be achieved via feedback from the receiver to the transmitter. This paper describes a channel emulation system comprised of a server/proxy/client combination that utilizes feedback from the client to adapt the number of Reed-Solomon parity symbols used to protect compressed video sequences against channel errors.

  2. Quality assessment of adaptive 3D video streaming

    Science.gov (United States)

    Tavakoli, Samira; Gutiérrez, Jesús; García, Narciso

    2013-03-01

    The streaming of 3D video contents is currently a reality to expand the user experience. However, because of the variable bandwidth of the networks used to deliver multimedia content, a smooth and high-quality playback experience could not always be guaranteed. Using segments in multiple video qualities, HTTP adaptive streaming (HAS) of video content is a relevant advancement with respect to classic progressive download streaming. Mainly, it allows resolving these issues by offering significant advantages in terms of both user-perceived Quality of Experience (QoE) and resource utilization for content and network service providers. In this paper we discuss the impact of possible HAS client's behavior while adapting to the network capacity on enduser. This has been done through an experiment of testing the end-user response to the quality variation during the adaptation procedure. The evaluation has been carried out through a subjective test of the end-user response to various possible clients' behaviors for increasing, decreasing, and oscillation of quality in 3D video. In addition, some of the HAS typical impairments during the adaptation has been simulated and their effects on the end-user perception are assessed. The experimental conclusions have made good insight into the user's response to different adaptation scenarios and visual impairments causing the visual discomfort that can be used to develop the adaptive streaming algorithm to improve the end-user experience.

  3. Struggles and Solutions for Streaming Video in the Online Classroom

    Science.gov (United States)

    Fruin, Christine

    2012-01-01

    The upcoming round of exemptions to the Digital Millennium Copyright Act of 1998 anticircumvention provision and the questions raised by the copyright infringement lawsuit filed against the against University of California, Los Angeles (UCLA) for its streaming video practices illustrate the problematic state of the law concerning the digitization…

  4. Social Backup and Sharing of Video using HTTP Adaptive Streaming

    NARCIS (Netherlands)

    Stokking, H.M.; Klos, V.B.; Jiang, J.; Casetti, C.

    2013-01-01

    This paper is on social backup, sharing and remote access of video using HTTP Adaptive Streaming. A social backup is a backup at the location, and thus on the equipment, of (close) friends and family. Backups are created at friends’ locations, matching the hosting user’s interest with the content an

  5. Social Backup and Sharing of Video using HTTP Adaptive Streaming

    NARCIS (Netherlands)

    Stokking, H.M.; Klos, V.B.; Jiang, J.; Casetti, C.

    2013-01-01

    This paper is on social backup, sharing and remote access of video using HTTP Adaptive Streaming. A social backup is a backup at the location, and thus on the equipment, of (close) friends and family. Backups are created at friends’ locations, matching the hosting user’s interest with the content

  6. Struggles and Solutions for Streaming Video in the Online Classroom

    Science.gov (United States)

    Fruin, Christine

    2012-01-01

    The upcoming round of exemptions to the Digital Millennium Copyright Act of 1998 anticircumvention provision and the questions raised by the copyright infringement lawsuit filed against the against University of California, Los Angeles (UCLA) for its streaming video practices illustrate the problematic state of the law concerning the digitization…

  7. Some Effects of Video Streaming on Educational Achievement

    Science.gov (United States)

    Boster, Franklin J.; Meyer, Gary S.; Roberto, Anthony J.; Inge, Carol; Strom, Renee

    2006-01-01

    Although much contemporary thinking leads to the expectation that communication technology, such as video streaming, enhances educational performance on the average, a dearth of strong evidence consistent or inconsistent with this claim precludes a thoughtful evaluation of it. A series of experiments designed to examine this proposition…

  8. Segment-based traffic smoothing algorithm for VBR video stream

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Transmission of variable bit rate (VBR) video, because of the burstiness of VBR video traffic, has high fluctuation in bandwidth requirement. Traffic smoothing algorithm is very efficient in reducing burstiness of the VBR video stream by transmitting data in a series of fixed rates. We propose in this paper a novel segment-based bandwidth allocation algorithm which dynamically adjusts the segmentation boundary and changes the transmission rate at the latest possible point so that the video segment will be extended as long as possible and the number of rate changes can be as small as possible while keeping the peak rate low. Simulation results showed that our approach has small bandwidth requirement, high bandwidth utilization and low computation cost.

  9. A Modified Multiview Video Streaming System Using 3-Tier Architecture

    Directory of Open Access Journals (Sweden)

    Mohamed M. Fouad

    2016-01-01

    Full Text Available In this paper, we present a modified inter-view prediction Multiview Video Coding (MVC scheme from the perspective of viewer's interactivity. When a viewer requests some view(s, our scheme leads to lower transmission bit-rate. We develop an interactive multiview video streaming system exploiting that modified MVC scheme. Conventional interactive multiview video systems require high bandwidth due to redundant data being transferred. With real data test sequences, clear improvements are shown using the proposed interactive multiview video system compared to competing ones in terms of the average transmission bit-rate and storage size of the decoded (i.e., transferred data with comparable rate-distortion.

  10. Streaming Video Games: Copyright Infringement or Protected Speech?

    Directory of Open Access Journals (Sweden)

    Eirik Evert Elias Jungar

    2016-12-01

    Full Text Available Streaming video games, that is, live broadcasting playing video games on the internet, is incredibly popular. Millions tune into twitch.tv daily to watch eSport tournaments, their favourite streamer, and chat with other viewers. But all is not rosy in the world of streaming games. Recently, some game developers have aggressively exercised their copyright to, firstly, claim part of the streamers’ revenue, and secondly, control the context in which their game is shown. The article analyzes whether game developers have, and should have, such rights under EU copyright law. Reaching the conclusion that video game streams infringe the game developer’s right to communicate their works to the public, I argue that freedom of expression can and should be used to rein in their rights in certain cases. Subjecting the lawfulness of streams to game developers’ good will risks stifling the expressions of streamers. The streamers, their audience, and even the copyright holders, would be worse off for it.

  11. Coping with handover effects in video streaming over cellular networks

    Institute of Scientific and Technical Information of China (English)

    BOUAZIZI Imed; HANNUKSELA Miska M.; RAUF Usama

    2006-01-01

    The 3rd generation partnership project (3GPP) has defined the protocols and codecs for implementing media streaming services over packet-switched 3G mobile networks. The specification is based on IETF RFCs on audio/video transport.It also adds new features to achieve better adaptation to the mobile network environment. In this paper, we propose an algorithm for handover detection and fast buffer refill that is based on the existing feedback and signaling mechanisms. The proposed algorithm refills the receiver buffer at a faster pace during a limited time frame after a hard handover is detected in order to achieve higher video quality.

  12. Error resilient concurrent video streaming over wireless mesh networks

    Institute of Scientific and Technical Information of China (English)

    LI Dan-jue; ZHANG Qian; CHUAH Chen-nee; YOO Ben S.J.

    2006-01-01

    In this paper, we propose a multi-source multi-path video streaming system for supporting high quality concurrent video-on-demand (VoD) services over wireless mesh networks (WMNs), and leverage forward error correction to enhance the error resilience of the system. By taking wireless interference into consideration, we present a more realistic networking model to capture the characteristics of WMNs and then design a route selection scheme using a joint rate/interference-distortion optimization framework to help the system optimally select concurrent streaming paths. We mathematically formulate such a route selection problem, and solve it heuristically using genetic algorithm. Simulation results demonstrate the effectiveness of our proposed scheme.

  13. QoE of Video Streaming over LTE Network

    OpenAIRE

    Uppu, Pradeep; Kadimpati, Sushanth

    2013-01-01

    In recent years, the mobile Internet has increased dramatically with the development of 3G and 4G technologies. Especially the usage of mobile broadband internet on the devices like cellular mobiles, Tablets and Laptops has skyrocketed. Among the multimedia applications video streaming is the most popular mobile application. But, making these services available to users in a cost effective way without compromising quality is a big challenge. The development of Long Term Evolution (LTE) techno...

  14. From videocassette to video stream: issues involved in re-purposing an existing educational video

    Directory of Open Access Journals (Sweden)

    Kerry Shephard

    2003-12-01

    Full Text Available This paper draws upon our experience of converting an existing educational videocassette into a video stream and presents a case study of the important issues that arose. The process was undertaken to apply some potential benefits of a new technology to support learners in higher education (HE. It was, however, by no means unproblematic and the issues that arose need to receive serious consideration if the potential of streaming technology is to be harnessed for more effective learning opportunities for students. 'Streaming' is a way of transmitting video (or other media files across the Internet (or by similar means. It is an alternative to downloaded delivery of these media and viewers do not have lengthy 'download waits'. A more comprehensive definition is provided elsewhere (Brown, 2002. The term used here to describe the processes involved in enabling a video recording, made for delivery via videocassette recorder (VCR, to be transmitted across the Internet is 're-purposing'. One process within this broad remit is that of making specific changes to the content of the video recording. This is referred to as 're-engineering'. The authors all have a strong commitment to the use of video in HE and have actively participated in the re-purposing reported here. They feel that since the Joint Information

  15. Efficiently detecting outlying behavior in video-game players

    Directory of Open Access Journals (Sweden)

    Young Bin Kim

    2015-12-01

    Full Text Available In this paper, we propose a method for automatically detecting the times during which game players exhibit specific behavior, such as when players commonly show excitement, concentration, immersion, and surprise. The proposed method detects such outlying behavior based on the game players’ characteristics. These characteristics are captured non-invasively in a general game environment. In this paper, cameras were used to analyze observed data such as facial expressions and player movements. Moreover, multimodal data from the game players (i.e., data regarding adjustments to the volume and the use of the keyboard and mouse was used to analyze high-dimensional game-player data. A support vector machine was used to efficiently detect outlying behaviors. We verified the effectiveness of the proposed method using games from several genres. The recall rate of the outlying behavior pre-identified by industry experts was approximately 70%. The proposed method can also be used for feedback analysis of various interactive content provided in PC environments.

  16. Constructible Authentic Representations: Designing Video Games That Enable Players to Utilize Knowledge Developed In-Game to Reason about Science

    Science.gov (United States)

    Holbert, Nathan R.; Wilensky, Uri

    2014-01-01

    While video games have become a source of excitement for educational designers, creating informal game experiences that players can draw on when thinking and reasoning in non-game contexts has proved challenging. In this paper we present a design principle for creating educational video games that enables players to draw on knowledge resources…

  17. In-Network Adaptation of Video Streams Using Network Processors

    Directory of Open Access Journals (Sweden)

    Mohammad Shorfuzzaman

    2009-01-01

    problem can be addressed, near the network edge, by applying dynamic, in-network adaptation (e.g., transcoding of video streams to meet available connection bandwidth, machine characteristics, and client preferences. In this paper, we extrapolate from earlier work of Shorfuzzaman et al. 2006 in which we implemented and assessed an MPEG-1 transcoding system on the Intel IXP1200 network processor to consider the feasibility of in-network transcoding for other video formats and network processor architectures. The use of “on-the-fly” video adaptation near the edge of the network offers the promise of simpler support for a wide range of end devices with different display, and so forth, characteristics that can be used in different types of environments.

  18. Some Video Games Can Increase the Player's Creativity

    Science.gov (United States)

    Moffat, David C.; Crombie, William; Shabalina, Olga

    2017-01-01

    It is said that playing video games might make people more creative. There is some evidence of an association, but no so far general theory about any psychological causes, or other key factors. In this study, we test the possibility that different sorts of video games may have different effects, on different types of creativity; or none at all.…

  19. Adapting the Streaming Video Based on the Estimated Motion Position

    Directory of Open Access Journals (Sweden)

    Hussein Muzahim Aziz

    2012-01-01

    Full Text Available In real time video streaming, the frames must meet their timing constraints, typically specified as their deadlines. Wireless networks may suffer from bandwidth limitations. To reduce the data transmission over the wireless networks, we propose an adaption technique in the server side by extracting a part of the video frames that considered as a Region Of Interest (ROI, and drop the part outside the ROI from the frames that are between reference frames. The estimated position of the selection of the ROI is computed by using the Sum of Squared Differences (SSD between consecutive frames. The reconstruction mechanism to the region outside the ROI is implemented in the mobile side by using linear interpolation between reference frames. We evaluate the proposed approach by using Mean Opinion Score (MOS measurements. MOS are used to evaluate two scenarios with equivalent encoding size, where the users observe the first scenario with low bit rate for the original videos, while for the second scenario the users observe our proposed approach with high bit rate. The results show that our technique significantly reduces the amounts of data are streamed over wireless networks, while the reconstruction mechanism will provides acceptable video quality.

  20. Video Streaming Transfer in a Smart Satellite Mobile Environment

    Directory of Open Access Journals (Sweden)

    Nedo Celandroni

    2009-01-01

    satellite link for transmitting video streams to a bus, where they are relayed to passengers' devices. We say that a bus works in smart mode if it takes advantage of the knowledge of the exact points where fixed obstacles will prevent receiving the satellite signal for a certain time period. This information is sent to the hub via a return channel. The hub, in its turn, suspends the transmissions to that specific bus for the given time interval, thus avoiding information losses and unnecessary bandwidth occupation. Buffering video packets, without any quality of service (QoS degradation, seamlessly compensates channel blockages up to a given duration. We determine the most appropriate transmission parameters for video streaming with good video QoS in a mobile satellite environment; moreover, we evaluate how “smart” the system can be in terms of bandwidth saving, by comparing it with the situation where the bus does not exploit the description of its route, still maintaining the same QoS requirements.

  1. Estimating Stream Surface Flow Velocities from Video Clips

    Science.gov (United States)

    Weijs, S. V.; Brauchli, T.; Chen, Z.; Huwald, H.

    2014-12-01

    Measuring surface flow velocities in streams can provide important information on discharge. This information is independent of water level, the most commonly used proxy for discharge and therefore has significant potential to reduce uncertainties. Advances in cheap and commonly used imaging devices (e.g. smartphone cameras) and image processing techniques offer new opportunities to get velocity information. Short video clips of streams can be used in combination with optical flow algorithms to get proxies for stream surface velocities. Here some initial results are presented and the main challenges are discussed, especially in view of using these techniques in a citizen science context (specifically the "WeSenseIt" project, a citizen observatory of water), where we try to minimize the need for site preparation and additional equipment needed to take measurements.

  2. Neural strategies for selective attention distinguish fast-action video game players.

    Science.gov (United States)

    Krishnan, Lavanya; Kang, Albert; Sperling, George; Srinivasan, Ramesh

    2013-01-01

    We investigated the psychophysical and neurophysiological differences between fast-action video game players (specifically first person shooter players, FPS) and non-action players (role-playing game players, RPG) in a visual search task. We measured both successful detections (hit rates) and steady-state visually evoked EEG potentials (SSVEPs). Search difficulty was varied along two dimensions: number of adjacent attended and ignored regions (1, 2 and 4), and presentation rate of novel search arrays (3, 8.6 and 20 Hz). Hit rates decreased with increasing presentation rates and number of regions, with the FPS players performing on average better than the RPG players. The largest differences in hit rate, between groups, occurred when four regions were simultaneously attended. We computed signal-to-noise ratio (SNR) of SSVEPs and used partial least squares regression to model hit rates, SNRs and their relationship at 3 Hz and 8.6 Hz. The following are the most significant results: RPG players' parietal responses to the attended 8.6 Hz flicker were predictive of hit rate and were positively correlated with it, indicating attentional signal enhancement. FPS players' parietal responses to the ignored 3 Hz flicker were predictive of hit rate and were positively correlated with it, indicating distractor suppression. Consistent with these parietal responses, RPG players' frontal responses to the attended 8.6 Hz flicker, increased as task difficulty increased with number of regions; FPS players' frontal responses to the ignored 3 Hz flicker increased with number of regions. Thus the FPS players appear to employ an active suppression mechanism to deploy selective attention simultaneously to multiple interleaved regions, while RPG primarily use signal enhancement. These results suggest that fast-action gaming can affect neural strategies and the corresponding networks underlying attention, presumably by training mechanisms of distractor suppression.

  3. Action video game players and deaf observers have larger Goldmann visual fields.

    Science.gov (United States)

    Buckley, David; Codina, Charlotte; Bhardwaj, Palvi; Pascalis, Olivier

    2010-03-05

    We used Goldmann kinetic perimetry to compare how training and congenital auditory deprivation may affect the size of the visual field. We measured the ability of action video game players and deaf observers to detect small moving lights at various locations in the central (around 30 degrees from fixation) and peripheral (around 60 degrees ) visual fields. Experiment 1 found that 10 habitual video game players showed significantly larger central and peripheral field areas than 10 controls. In Experiment 2 we found that 13 congenitally deaf observers had significantly larger visual fields than 13 hearing controls for both the peripheral and central fields. Here the greatest differences were found in the lower parts of the fields. Comparison of the two groups showed that whereas VGP players have a more uniform increase in field size in both central and peripheral fields deaf observers show non-uniform increases with greatest increases in lower parts of the visual field.

  4. Effects of Video Streaming Technology on Public Speaking Students' Communication Apprehension and Competence

    Science.gov (United States)

    Dupagne, Michel; Stacks, Don W.; Giroux, Valerie Manno

    2007-01-01

    This study examines whether video streaming can reduce trait and state communication apprehension, as well as improve communication competence, in public speaking classes. Video streaming technology has been touted as the next generation of video feedback for public speaking students because it is not limited by time or space and allows Internet…

  5. Effects of Video Streaming Technology on Public Speaking Students' Communication Apprehension and Competence

    Science.gov (United States)

    Dupagne, Michel; Stacks, Don W.; Giroux, Valerie Manno

    2007-01-01

    This study examines whether video streaming can reduce trait and state communication apprehension, as well as improve communication competence, in public speaking classes. Video streaming technology has been touted as the next generation of video feedback for public speaking students because it is not limited by time or space and allows Internet…

  6. Contributions to Using IT in Education: An Educational Video Player

    Directory of Open Access Journals (Sweden)

    Ciprian CUCU

    2010-01-01

    Full Text Available Following the trends of IT use in education we propose four main principles of educational application development: anytime-anywhere access (including access for mobile devices; user-generated content; assigning users an active role inside the platform; creating a correlation between natural activities and educational activities – adding fun into the equation. With these principles in mind we developed a small Educational Player – a movie player that connects to a database to show information relevant to the events in the movie, more specific to the exact key-frame (in the movie time-line at the moment of the request. Though the application is still in a conceptual form, its possibilities make us confident in its future success either as an informal way of learning, or by using it in a formal educational context either as an e-learning tool, either as interactivity tool in a traditional classroom setting.

  7. Exploring Self-regulation of More or Less Expert College-Age Video Game Players: A Sequential Explanatory Design

    Science.gov (United States)

    Yilmaz Soylu, Meryem; Bruning, Roger H.

    2016-01-01

    This study examined differences in self-regulation among college-age expert, moderately expert, and non-expert video game players in playing video games for fun. Winne's model of self-regulation (Winne, 2001) guided the study. The main assumption of this study was that expert video game players used more processes of self-regulation than the less-expert players. We surveyed 143 college students about their game playing frequency, habits, and use of self-regulation. Data analysis indicated that while playing recreational video games, expert gamers self-regulated more than moderately expert and non-expert players and moderately expert players used more processes of self-regulation than non-experts. Semi-structured interviews also were conducted with selected participants at each of the expertise levels. Qualitative follow-up analyses revealed five themes: (1) characteristics of expert video gamers, (2) conditions for playing a video game, (3) figuring out a game, (4) how gamers act and, (5) game context. Overall, findings indicated that playing a video game is a highly self-regulated activity and that becoming an expert video game player mobilizes multiple sets of self-regulation related skills and processes. These findings are seen as promising for educators desiring to encourage student self-regulation, because they indicate the possibility of supporting students via recreational video games by recognizing that their play includes processes of self-regulation. PMID:27729881

  8. Enhanced visual short-term memory in action video game players.

    Science.gov (United States)

    Blacker, Kara J; Curby, Kim M

    2013-08-01

    Visual short-term memory (VSTM) is critical for acquiring visual knowledge and shows marked individual variability. Previous work has illustrated a VSTM advantage among action video game players (Boot et al. Acta Psychologica 129:387-398, 2008). A growing body of literature has suggested that action video game playing can bolster visual cognitive abilities in a domain-general manner, including abilities related to visual attention and the speed of processing, providing some potential bases for this VSTM advantage. In the present study, we investigated the VSTM advantage among video game players and assessed whether enhanced processing speed can account for this advantage. Experiment 1, using simple colored stimuli, revealed that action video game players demonstrate a similar VSTM advantage over nongamers, regardless of whether they are given limited or ample time to encode items into memory. Experiment 2, using complex shapes as the stimuli to increase the processing demands of the task, replicated this VSTM advantage, irrespective of encoding duration. These findings are inconsistent with a speed-of-processing account of this advantage. An alternative, attentional account, grounded in the existing literature on the visuo-cognitive consequences of video game play, is discussed.

  9. Joint rate control and scheduling for wireless uplink video streaming

    Institute of Scientific and Technical Information of China (English)

    HUANG Jian-wei; LI Zhu; CHIANG Mung; KATSAGGELOS Aggelos K.

    2006-01-01

    We solve the problem of uplink video streaming in CDMA cellular networks by jointly designing the rate control and scheduling algorithms. In the pricing-based distributed rate control algorithm, the base station announces a price for the per unit average rate it can support, and the mobile devices choose their desired average transmission rates by balancing their video quality and cost of transmission. Each mobile device then determines the specific video frames to transmit by a video summarization process. In the time-division-multiplexing (TDM) scheduling algorithm, the base station collects the information on frames to be transmitted from all devices within the current time window, sorts them in increasing order of deadlines, and schedules the transmissions in a TDM fashion. This joint algorithm takes advantage of the multi-user content diversity, and maximizes the network total utility (i.e., minimize the network total distortion), while satisfying the delivery deadline constraints. Simulations showed that the proposed algorithm significantly outperforms the constant rate provision algorithm.

  10. Mobile P2P Trusted On-Demand Video Streaming

    CERN Document Server

    Iyer, Thava; Rizvandi, Nikzad Babaii; Varghese, Benoy; Boreli, Roksana

    2012-01-01

    We propose to demonstrate a mobile server assisted P2P system for on-demand video streaming. Our proposed solution uses a combination of 3G and ad-hoc Wi-Fi connections, to enable mobile devices to download content from a centralised server in a way that minimises the 3G bandwidth use and cost. On the customised GUI, we show the corresponding reduction in 3G bandwidth achieved by increasing the number of participating mobile devices in the combined P2P and ad-hoc Wi- Fi network, while demonstrating the good video playout quality on each of the mobiles. We also demonstrate the implemented trust mechanism which enables mobiles to only use trusted adhoc connections. The system has been implemented on Android based smartphones.

  11. Music as Active Information Resource for Players in Video Games

    Science.gov (United States)

    Nagorsnick, Marian; Martens, Alke

    2015-01-01

    In modern video games, music can come in different shapes: it can be developed on a very high compositional level, with sophisticated sound elements like in professional film music; it can be developed on a very coarse level, underlying special situations (like danger or attack); it can also be automatically generated by sound engines. However, in…

  12. Streaming Videos in Peer Assessment to Support Training Pre-Service Teachers

    Science.gov (United States)

    Wu, Cheng-Chih; Kao, Hue-Ching

    2008-01-01

    A web-based peer assessment system using video streaming technology was implemented to support the training of pre-service teachers. The peer assessment process was synchronized with viewing of peer teaching videos so that comments could be linked to the relevant position on the video. When one viewed a comment, the associated video segment could…

  13. 4kUHD H264 Wireless Live Video Streaming Using CUDA

    OpenAIRE

    Adeyemi-Ejeye, A. O.; Walker, S.

    2014-01-01

    Ultrahigh definition video streaming has been explored in recent years. Most recently the possibility of 4kUHD video streaming over wireless 802.11n was presented, using preencoded video. Live encoding for streaming using x264 has proven to be very slow. The use of parallel encoding has been explored to speed up the process using CUDA. However there hasnot been a parallel implementation for video streaming. We therefore present for the first time a novel implementation of 4kUHD live encoding ...

  14. On the Interaction of Adaptive Video Streaming with Content-Centric Networking

    OpenAIRE

    Grandl, Reinhard; Kai SU; Westphal, Cedric

    2013-01-01

    Two main trends in today's internet are of major interest for video streaming services: most content delivery platforms coincide towards using adaptive video streaming over HTTP and new network architectures allowing caching at intermediate points within the network. We investigate one of the most popular streaming service in terms of rate adaptation and opportunistic caching. Our experimental study shows that the streaming client's rate selection trajectory, i.e., the set of selected segment...

  15. Cognitive Modeling of Video Game Player User Experience

    Science.gov (United States)

    Bohil, Corey J.; Biocca, Frank A.

    2010-01-01

    This paper argues for the use of cognitive modeling to gain a detailed and dynamic look into user experience during game play. Applying cognitive models to game play data can help researchers understand a player's attentional focus, memory status, learning state, and decision strategies (among other things) as these cognitive processes occurred throughout game play. This is a stark contrast to the common approach of trying to assess the long-term impact of games on cognitive functioning after game play has ended. We describe what cognitive models are, what they can be used for and how game researchers could benefit by adopting these methods. We also provide details of a single model - based on decision field theory - that has been successfUlly applied to data sets from memory, perception, and decision making experiments, and has recently found application in real world scenarios. We examine possibilities for applying this model to game-play data.

  16. Delay Discounting of Video Game Players: Comparison of Time Duration Among Gamers.

    Science.gov (United States)

    Buono, Frank D; Sprong, Matthew E; Lloyd, Daniel P; Cutter, Christopher J; Printz, Destiny M B; Sullivan, Ryan M; Moore, Brent A

    2017-02-01

    Video game addiction or Internet game disorder, as proposed by the DSM-5 (Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition), has similar criterion characteristics to other impulse control disorders. There is limited research examining video game addiction within a behavioral economic framework using delay discounting. The current study evaluated delay-discounting patterns of money and video game play by usual weekly hours of video game play. A total of 104 participants were split into 1 of 3 groups of video game players (low, medium, and high) and were asked to complete a monetary and video game discounting procedure through an online survey. Results showed significant differences between groups within both the monetary (p = 0.003) and video game discounting procedures (p = 0.004). Additionally, a positive linear relationship was noted between the groups across both procedures. The results of the current article reinforce previous findings that more hours of video game use are associated with greater impulsivity and provide implications for future research.

  17. Adaptive Bit Rate Video Streaming Through an RF/Free Space Optical Laser Link

    Directory of Open Access Journals (Sweden)

    A. Akbulut

    2010-06-01

    Full Text Available This paper presents a channel-adaptive video streaming scheme which adjusts video bit rate according to channel conditions and transmits video through a hybrid RF/free space optical (FSO laser communication system. The design criteria of the FSO link for video transmission to 2.9 km distance have been given and adaptive bit rate video streaming according to the varying channel state over this link has been studied. It has been shown that the proposed structure is suitable for uninterrupted transmission of videos over the hybrid wireless network with reduced packet delays and losses even when the received power is decreased due to weather conditions.

  18. Layer-based buffer aware rate adaptation design for SHVC video streaming

    Science.gov (United States)

    Gudumasu, Srinivas; Hamza, Ahmed; Asbun, Eduardo; He, Yong; Ye, Yan

    2016-09-01

    This paper proposes a layer based buffer aware rate adaptation design which is able to avoid abrupt video quality fluctuation, reduce re-buffering latency and improve bandwidth utilization when compared to a conventional simulcast based adaptive streaming system. The proposed adaptation design schedules DASH segment requests based on the estimated bandwidth, dependencies among video layers and layer buffer fullness. Scalable HEVC video coding is the latest state-of-art video coding technique that can alleviate various issues caused by simulcast based adaptive video streaming. With scalable coded video streams, the video is encoded once into a number of layers representing different qualities and/or resolutions: a base layer (BL) and one or more enhancement layers (EL), each incrementally enhancing the quality of the lower layers. Such layer based coding structure allows fine granularity rate adaptation for the video streaming applications. Two video streaming use cases are presented in this paper. The first use case is to stream HD SHVC video over a wireless network where available bandwidth varies, and the performance comparison between proposed layer-based streaming approach and conventional simulcast streaming approach is provided. The second use case is to stream 4K/UHD SHVC video over a hybrid access network that consists of a 5G millimeter wave high-speed wireless link and a conventional wired or WiFi network. The simulation results verify that the proposed layer based rate adaptation approach is able to utilize the bandwidth more efficiently. As a result, a more consistent viewing experience with higher quality video content and minimal video quality fluctuations can be presented to the user.

  19. Live streaming video for medical education: a laboratory model.

    Science.gov (United States)

    Gandsas, Alejandro; McIntire, Katherine; Palli, Guillermo; Park, Adrian

    2002-10-01

    At the University of Kentucky (UK), we applied streaming video technology to develop a webcast model that will allow institutions to broadcast live and prerecorded surgeries, conferences, and courses in real time over networks (the Internet or an intranet). We successfully broadcast a prerecorded laparoscopic paraesophageal hernia repair to domestic and international clients by using desktop computers equipped with off-the-shelf, streaming-enabled software and standard hardware and operating systems. A web-based user interface made accessing the educational material as simple as a mouse click and allowed clients to participate in the broadcast event via an embedded e-mail/chat module. Three client computers (two connected to the Internet and a third connected to the UK intranet) requested and displayed the surgical film by means of seven common network connection configurations. Significantly, no difference in image resolution was detected with the use of a connection speed faster than 128 kilobytes per second (kbps). At this connection speed, an average bandwidth of 32.7 kbps was used, and although a 15-second delay was experienced from the time of data request to data display, the surgical film streamed continuously from beginning to end at a mean rate of 14.4 frames per second (fps). The clients easily identified all anatomic structures in full color motion, clearly followed all steps of the surgical procedure, and successfully asked questions and made comments by using the e-mail/chat module while viewing the surgery. With minimal financial investment, we have created an interactive virtual classroom with the potential to attract a global audience. Our webcast model represents a simple and practical method for institutions to supplement undergraduate and graduate surgical education and offer continuing medical education credits in a way that is convenient for clients (surgeons, students, residents, others). In the future, physicians may access streaming webcast

  20. Scalable Video Streaming Adaptive to Time-Varying IEEE 802.11 MAC Parameters

    Science.gov (United States)

    Lee, Kyung-Jun; Suh, Doug-Young; Park, Gwang-Hoon; Huh, Jae-Doo

    This letter proposes a QoS control method for video streaming service over wireless networks. Based on statistical analysis, the time-varying MAC parameters highly related to channel condition are selected to predict available bitrate. Adaptive bitrate control of scalably-encoded video guarantees continuity in streaming service even if the channel condition changes abruptly.

  1. Max-Weight Scheduling and Quality-Aware Streaming for Device-to-Device Video Delivery

    OpenAIRE

    Kim, Joongheon; Molisch, Andreas F.; Caire, Giuseppe

    2014-01-01

    We propose and analyze centralized and distributed algorithms for device-to-device video scheduling and streaming. The proposed algorithms address jointly the problems of device-to-device link scheduling and video quality adaptation in streaming. Our simulations show that the proposed algorithms significantly outperform conventional separated approaches that treat these two problems independently.

  2. Streaming video - præsentation af trailere over internettet

    DEFF Research Database (Denmark)

    Jensen, Ole Riis; Forchhammer, Søren

    1998-01-01

    Som et led i Tele Danmark Kabel TV's markedsføring ønsker man at kunne præsentere filmtrailere og andet materiale i form af levende billeder til kunderne via Wold Wide Web (WWW). Dette projekts hovedformål er at undersøge eksisterende metoder og udvikle redskaber til at præsentere en tilsvarende ...... interaktiv tjeneste baseret på realtidsfremvisning af videotrailere, såkaldt streaming video og audio, og hvor brugeren kan få information om en film der tænkes udbudt på en pay-per-view kanal. Der i arbejdets forløb blevet opbygget en demo, der implementerer en sådan tjeneste....

  3. mVideoCast: Mobile, real time ROI detection and streaming

    CERN Document Server

    Carter, Scott; Adcock, John

    2010-01-01

    A variety of applications are emerging to support streaming video from mobile devices. However, many tasks can benefit from streaming specific content rather than the full video feed which may include irrelevant, private, or distracting content. We describe a system that allows users to capture and stream targeted video content captured with a mobile device. The application incorporates a variety of automatic and interactive techniques to identify and segment desired content in the camera view, allowing the user to publish a more focused video.

  4. Applicability of Existing Objective Metrics of Perceptual Quality for Adaptive Video Streaming

    DEFF Research Database (Denmark)

    Søgaard, Jacob; Krasula, Lukás; Shahid, Muhammad

    2016-01-01

    Objective video quality metrics are designed to estimate the quality of experience of the end user. However, these objective metrics are usually validated with video streams degraded under common distortion types. In the presented work, we analyze the performance of published and known full......-reference and noreference quality metrics in estimating the perceived quality of adaptive bit-rate video streams knowingly out of scope. Experimental results indicate not surprisingly that state of the art objective quality metrics overlook the perceived degradations in the adaptive video streams and perform poorly...

  5. A systematic review of usability test metrics for mobile video streaming apps

    Science.gov (United States)

    Hussain, Azham; Mkpojiogu, Emmanuel O. C.

    2016-08-01

    This paper presents the results of a systematic review regarding the usability test metrics for mobile video streaming apps. In the study, 238 studies were found, but only 51 relevant papers were eventually selected for the review. The study reveals that time taken for video streaming and the video quality were the two most popular metrics used in the usability tests for mobile video streaming apps. Besides, most of the studies concentrated on the usability of mobile TV as users are switching from traditional TV to mobile TV.

  6. On subjective quality assessment of adaptive video streaming via crowdsourcing and laboratory based experiments

    DEFF Research Database (Denmark)

    Søgaard, Jacob; Shahid, Muhammad; Pokhrel, Jeevan

    2017-01-01

    Video streaming services are offered over the Internet and since the service providers do not have full control over the network conditions all the way to the end user, streaming technologies have been developed to maintain the quality of service in these varying network conditions i.e. so called...... adaptive video streaming. In order to cater for users' Quality of Experience (QoE) requirements, HTTP based adaptive streaming solutions of video services have become popular. However, the keys to ensure the users a good QoE with this technology is still not completely understood. User QoE feedback...... assessment of video quality is gaining popularity as an alternative method. This article presents insights into a study that investigates perceptual preferences of various adaptive video streaming scenarios through crowdsourcing based and laboratory based subjective assessment. The major novel contribution...

  7. Control of Perceptual Image Quality Based on PID for Streaming Video

    Institute of Scientific and Technical Information of China (English)

    SONG Jian-xin

    2003-01-01

    Constant levels of perceptual quality of streaming video is what ideall users expect. In most cases, however, they receive time-varying levels of quality of video. In this paper, the author proposes a new control method of perceptual quality in variable bit rate video encoding for streaming video. The image quality calculation based on the perception of human visual systems is presented. Quantization properties of DCT coefficients are analyzed to control effectively. Quantization scale factors are ascertained based on the visual mask effect. A Proportional Integral Difference ( PID ) controller is used to control the image quality. Experimental results show that this method improves the perceptual quality uniformity of encoded video.

  8. Flexible Broadcasting of Scalable Video Streams in Broadband Wireless System

    Directory of Open Access Journals (Sweden)

    D. Lavanya

    2015-02-01

    Full Text Available This paper presents a novel cross-layer optimization framework to improve the quality of user experience (QOE and energy efficiency of the heterogeneous wireless multimedia broadcast receivers. User grouping is based on the respective UE resolution capabilities and received SNR. A UE capability is determined by the BS at the time of service subscription, when the UE sends its type information, i.e., the number of layers it wants to receive. The UE periodically updated its channel condition to the BS through the uplink channel. This joint optimization is achieved by grouping the users based on their device capabilities and estimated channel conditions experienced by them and broadcasting adaptive content to these groups. The adaptive multimedia content is obtained by using scalable video coding (SVC with optimal source encoding parameters resulted from an innovative cooperative game. Energy saving at user terminals results from using a layer-aware time slicing approach in the transmission stage. Time slicing approach allows discontinuous reception at the UEs, thereby facilitating the UE to turn-off the radio when not receiving data bursts and hence saving energy. A trade-off between energy saving and QOE is observed, and is incorporated in the definition of a utility function of the players in the formulated heterogeneous user composition and physical channel aware game. An adaptive modulation and coding scheme is also optimally incorporated in order to maximize the reception quality of the broadcast receivers, while maximizing the network broadcast capacity.

  9. Vertical Handover and Video Streaming Over Cloud in 4G Heterogeneous Overlay Wireless Networks

    Directory of Open Access Journals (Sweden)

    Dr.P.Vetrivelan

    2015-10-01

    Full Text Available 4G enables the integration and interworking of all wireless systems. The users always think of seamless streaming of multimedia over various networks. The proposed technique focus on providing “non-terminating” video streaming for mobile users while moving over various networks, the adaptive mobile streaming over mobile networks helps to provide streaming of video . The streaming delays can be reduced by constructing private agents using cloud to provide adaptive video streaming to mobile devices, some algorithm like SVC H.264f is used to reduce buffering during streaming and also in switching over one network to another network. Vertical Handover is carried out in order to reduce handoff by constructing MDP based algorithms using the QoS parameters such as bandwidth, delay, jitter, bit error rate and cost.

  10. High Quality of Service on Video Streaming in P2P Networks using FST-MDC

    CERN Document Server

    Jaganathan, Suresh; 10.5121/ijma.2011.3203

    2011-01-01

    Video streaming applications have newly attracted a large number of participants in a distribution network. Traditional client-server based video streaming solutions sustain precious bandwidth provision rate on the server. Recently, several P2P streaming systems have been organized to provide on-demand and live video streaming services on the wireless network at reduced server cost. Peer-to-Peer (P2P) computing is a new pattern to construct disseminated network applications. Typical error control techniques are not very well matched and on the other hand error prone channels has increased greatly for video transmission e.g., over wireless networks and IP. These two facts united together provided the essential motivation for the development of a new set of techniques (error concealment) capable of dealing with transmission errors in video systems. In this paper, we propose an flexible multiple description coding method named as Flexible Spatial-Temporal (FST) which improves error resilience in the sense of fra...

  11. Analisis Kualitas Layanan Video Live Streaming pada Jaringan Lokal Universitas Telkom

    Directory of Open Access Journals (Sweden)

    Anggelina I Diwi

    2014-09-01

    Full Text Available Streaming adalah salah satu bentuk teknologi yang memperkenankan file digunakan secara langsung tanpa menunggu selesainya unggahan (download dan berlangsung secara kontinyu tanpa interupsi. Untuk mengaplikasikan video streaming kedalam jaringan, diperlukan pertama-tama untuk mengkalkulasi bandwidth yang tersedia, untuk mendukung transmisi data. Bandwidth merupakan parameter penting untuk streaming di dalam jaringan. Makin besar bandwidth yang tersedia, makin baik kualitas video yang ditampilkan. Penelitian ini bertujuan untuk mengetahui kebutuhan bandwidth untuk layanan video live streaming; metode yang digunakan di dalam penelitian ini adalah dengan mengadakan pengukuran unjuk kerja jaringan secara langsung di lapangan, yaitu LAN di lingkungan Universitas Telkom. Implementasi media streaming server-client di dalam penelitian ini menggunakan file video yang berbeda, berdasarkan jumlah frame yang dikirim (fps. Skenario video streaming ini dilakukan dengan menggunakan latar belakang  trafik  yang  bervariasi,  untuk  melihat  pengaruhnya terhadap parameter QoS jaringan. Pengujian performansi Quality of Service (QoS dalam implementasi video live streaming ini menggunakan software network analyzer Wireshark. Hasil penilitian menunjukkan, bahwa video dengan laju frame lebih besar dari 15 fps, memberikan jitter dan throughput yang besar pula.

  12. Video game players show higher performance but no difference in speed of attention shifts.

    Science.gov (United States)

    Mack, David J; Wiesmann, Helene; Ilg, Uwe J

    2016-09-01

    Video games have become both a widespread leisure activity and a substantial field of research. In a variety of tasks, video game players (VGPs) perform better than non-video game players (NVGPs). This difference is most likely explained by an alteration of the basic mechanisms underlying visuospatial attention. More specifically, the present study hypothesizes that VGPs are able to shift attention faster than NVGPs. Such alterations in attention cannot be disentangled from changes in stimulus-response mappings in reaction time based measurements. Therefore, we used a spatial cueing task with varying cue lead times (CLTs) to investigate the speed of covert attention shifts of 98 male participants divided into 36 NVGPs and 62 VGPs based on their weekly gaming time. VGPs exhibited higher peak and mean performance than NVGPs. However, we did not find any differences in the speed of covert attention shifts as measured by the CLT needed to achieve peak performance. Thus, our results clearly rule out faster stimulus-response mappings as an explanation for the higher performance of VGPs in line with previous studies. More importantly, our data do not support the notion of faster attention shifts in VGPs as another possible explanation.

  13. Examination of mechanisms underlying enhanced memory performance in action video game players: a pilot study.

    Science.gov (United States)

    Li, Xianchun; Cheng, Xiaojun; Li, Jiaying; Pan, Yafeng; Hu, Yi; Ku, Yixuan

    2015-01-01

    Previous studies have shown enhanced memory performance resulting from extensive action video game playing. The mechanisms underlying the cognitive benefit were investigated in the current study. We presented two types of retro-cues, with variable intervals to memory array (Task 1) or test array (Task 2), during the retention interval in a change detection task. In Task 1, action video game players demonstrated steady performance while non-action video game players showed decreased performance as cues occurred later, indicating their performance difference increased as the cue-to-memory-array intervals became longer. In Task 2, both participant groups increased their performance at similar rates as cues presented later, implying the performance difference in two groups were irrespective of the test-array-to-cue intervals. These findings suggested that memory benefit from game plays is not attributable to the higher ability of overcoming interference from the test array, but to the interactions between the two processes of protection from decay and resistance from interference, or from alternative hypotheses. Implications for future studies were discussed.

  14. 4kUHD H264 Wireless Live Video Streaming Using CUDA

    Directory of Open Access Journals (Sweden)

    A. O. Adeyemi-Ejeye

    2014-01-01

    Full Text Available Ultrahigh definition video streaming has been explored in recent years. Most recently the possibility of 4kUHD video streaming over wireless 802.11n was presented, using preencoded video. Live encoding for streaming using x264 has proven to be very slow. The use of parallel encoding has been explored to speed up the process using CUDA. However there hasnot been a parallel implementation for video streaming. We therefore present for the first time a novel implementation of 4kUHD live encoding for streaming over a wireless network at low bitrate indoors, using CUDA for parallel H264 encoding. Our experimental results are used to verify our claim.

  15. Using GPU-generated virtual video stream for multi-sensor system

    Science.gov (United States)

    Liao, Dezhi; Hennessey, Brian

    2006-05-01

    Security and intelligence services are increasingly turning toward multi-sensor video surveillance which requires human ability to successfully fuse and comprehend the information provided by videos. A training system using the same front end as real multi-sensor system for users can significantly increase such human ability. The training system always needs scenarios replicating stressful situations which are videotaped in advance and played later. This not only puts a limitation on the training scenarios but also brings a high cost. This paper introduces a new framework, virtual video capture device for such training system. Using the latest graphics processing units (GPUs) technology, multiple video streams composed of computer graphics (CG) are generated on one high-end PC and ublished to a video stream server. Thus users can be trained using both real video streams and virtual video streams on one system. It also enables the training system to use real video streams incorporating augmented reality to improve situation awareness of the human.

  16. Video Streaming in Peer-to-Peer Networks Using Network Coding Renders Efficient Video Cassette Recorder Operations

    Directory of Open Access Journals (Sweden)

    K. V. Pradeepthi

    2012-01-01

    Full Text Available Problem statement: Major technological development in recent years has led to the usage of shared streaming solutions by Peer-to-Peer (P2P Video-on-Demand (VoD systems in the Internet. Video streaming in P2P network systems has ample amount of loss of video packets due to network disabilities such as congestion, intrusion, connectivity problems, excessive network collisions etc. Adding onto the video streaming problems, Video Cassette Recorder (VCR operations require flexibility of playback to the user. So, any missing or randomized packets from the video have to be instantaneously corrected and generated appropriately. Approach: In this paper, we study the working of VoD streaming system that uses Network Coding (NC for improving the delivered video content at the end-user by correcting the error packets. We, study that NC not only, materializes uninterrupted playback but efficiency in VCR operations particularly, the seek operation have also improved the user perceived quality of videos. Our setup handles the NC generator present at the proxy between the media server and the peer clients, reducing the overhead at the server. The relevant packets that are lost within each peer-client are generated with the NC packets. Results: The receiver detects error due to loss of packets and corrects at a much faster pace than the time consumed for retransmission. This helps in improving user efficiency in VCR operations also. Though, NC provides added advantage in P2P VoD systems, there is initial transmission delay, a time cost incurred in video streaming. This time cost is rather small when compared to the difficulties within the Internet for the retransmissions. Conclusion: From the study we observe, that NC when applied to P2P VoD has few difficulties. They are complexity in implementing NC and tradeoffs on the part of NC in video streaming. Based on time and cache constraints these difficulties are not overwhelming when the actual benefits reaped are

  17. Energy saving approaches for video streaming on smartphone based on QoE modeling

    DEFF Research Database (Denmark)

    Ballesteros, Luis Guillermo Martinez; Ickin, Selim; Fiedler, Markus

    2016-01-01

    In this paper, we study the influence of video stalling on QoE. We provide QoE models that are obtained in realistic scenarios on the smartphone, and provide energy-saving approaches for smartphone by leveraging the proposed QoE models in relation to energy. Results show that approximately 5J...... is saved in a 3 minutes video clip with an acceptable Mean Opinion Score (MOS) level when the video frames are skipped. If the video frames are not skipped, then it is suggested to avoid freezes during a video stream as the freezes highly increase the energy waste on the smartphones....

  18. Using learning styles and viewing styles in streaming video

    NARCIS (Netherlands)

    de Boer, Jelle; Kommers, Petrus A.M.; de Brock, Bert

    2011-01-01

    Improving the effectiveness of learning when students observe video lectures becomes urgent with the rising advent of (web-based) video materials. Vital questions are how students differ in their learning preferences and what patterns in viewing video can be detected in log files. Our experiments

  19. Using learning styles and viewing styles in streaming video

    NARCIS (Netherlands)

    de Boer, Jelle; Kommers, Piet A. M.; de Brock, Bert

    Improving the effectiveness of learning when students observe video lectures becomes urgent with the rising advent of (web-based) video materials. Vital questions are how students differ in their learning preferences and what patterns in viewing video can be detected in log files. Our experiments

  20. Video on the semantic web: experiences with media streams

    NARCIS (Netherlands)

    Geurts, J.P.T.M.; Ossenbruggen, J.R. van

    2004-01-01

    In this paper, we report our experiences with the use of SemanticWeb technology for annotating digital video material.Web technology is used to transform a large, existing video ontology embedded in an annotation tool into a commonly accessible format. The recombination of existing video material is

  1. Using learning styles and viewing styles in streaming video

    NARCIS (Netherlands)

    Boer, de Jelle; Kommers, Piet A.M.; Brock, de Bert

    2011-01-01

    Improving the effectiveness of learning when students observe video lectures becomes urgent with the rising advent of (web-based) video materials. Vital questions are how students differ in their learning preferences and what patterns in viewing video can be detected in log files. Our experiments i

  2. Using learning styles and viewing styles in streaming video

    NARCIS (Netherlands)

    de Boer, Jelle; Kommers, Piet A. M.; de Brock, Bert

    2011-01-01

    Improving the effectiveness of learning when students observe video lectures becomes urgent with the rising advent of (web-based) video materials. Vital questions are how students differ in their learning preferences and what patterns in viewing video can be detected in log files. Our experiments in

  3. Using learning styles and viewing styles in streaming video

    NARCIS (Netherlands)

    de Boer, Jelle; Kommers, Petrus A.M.; de Brock, Bert

    2011-01-01

    Improving the effectiveness of learning when students observe video lectures becomes urgent with the rising advent of (web-based) video materials. Vital questions are how students differ in their learning preferences and what patterns in viewing video can be detected in log files. Our experiments in

  4. The effectiveness of streaming video on medical student learning: a case study.

    Science.gov (United States)

    Bridge, Patrick D; Jackson, Matt; Robinson, Leah

    2009-08-19

    Information technology helps meet today's medical students' needs by providing multiple curriculum delivery methods. Video streaming is an e-learning technology that uses the Internet to deliver curriculum while giving the student control of the content's delivery. There have been few studies conducted on the effectiveness of streaming video in medical schools. A 5-year retrospective study was conducted using three groups of students (n = 1736) to determine if the availability of streaming video in Years 1-2 of the basic science curriculum affected overall Step 1 scores for first-time test-takers. The results demonstrated a positive effect on program outcomes as streaming video became more readily available to students. Based on these findings, streaming video technology seems to be a viable tool to complement in-class delivery methods, to accommodate the needs of medical students, and to provide options for meeting the challenges of delivering the undergraduate medical curriculum. Further studies need to be conducted to continue validating the effectiveness of streaming video technology.

  5. Scene change detection for video retrieval on MPEG streams

    Science.gov (United States)

    Kang, Eung-Kwan; Kim, Sung-Joo; Jahng, SurngGabb; Song, Ho-Keun; Choi, Jong S.

    2000-05-01

    IN this paper, we propose a new scene change detection (SCD) algorithm, and also provide a novel video-indexing scheme for fast content-based browsing and retrieval in video databases. We detect scene changes from the MPEG video sequence, and extract key frames to represent contents of a shot. Then, we perform the video indexing by applying the rosette pattern to the extracted key frames, and retrieve them. Our SCD method is better than the conventional ones in terms of the SCD performance. Moreover, by applying the rosette pattern for indexing, we can remarkably reduce the number of pixels required to index and excellently retrieve the video scene.

  6. Real-time video streaming in mobile cloud over heterogeneous wireless networks

    Science.gov (United States)

    Abdallah-Saleh, Saleh; Wang, Qi; Grecos, Christos

    2012-06-01

    Recently, the concept of Mobile Cloud Computing (MCC) has been proposed to offload the resource requirements in computational capabilities, storage and security from mobile devices into the cloud. Internet video applications such as real-time streaming are expected to be ubiquitously deployed and supported over the cloud for mobile users, who typically encounter a range of wireless networks of diverse radio access technologies during their roaming. However, real-time video streaming for mobile cloud users across heterogeneous wireless networks presents multiple challenges. The network-layer quality of service (QoS) provision to support high-quality mobile video delivery in this demanding scenario remains an open research question, and this in turn affects the application-level visual quality and impedes mobile users' perceived quality of experience (QoE). In this paper, we devise a framework to support real-time video streaming in this new mobile video networking paradigm and evaluate the performance of the proposed framework empirically through a lab-based yet realistic testing platform. One particular issue we focus on is the effect of users' mobility on the QoS of video streaming over the cloud. We design and implement a hybrid platform comprising of a test-bed and an emulator, on which our concept of mobile cloud computing, video streaming and heterogeneous wireless networks are implemented and integrated to allow the testing of our framework. As representative heterogeneous wireless networks, the popular WLAN (Wi-Fi) and MAN (WiMAX) networks are incorporated in order to evaluate effects of handovers between these different radio access technologies. The H.264/AVC (Advanced Video Coding) standard is employed for real-time video streaming from a server to mobile users (client nodes) in the networks. Mobility support is introduced to enable continuous streaming experience for a mobile user across the heterogeneous wireless network. Real-time video stream packets

  7. Performance Evaluation of Concurrent Multipath Video Streaming in Multihomed Mobile Networks

    Directory of Open Access Journals (Sweden)

    James Nightingale

    2013-01-01

    Full Text Available High-quality real-time video streaming to users in mobile networks is challenging due to the dynamically changing nature of the network paths, particularly the limited bandwidth and varying end-to-end delay. In this paper, we empirically investigate the performance of multipath streaming in the context of multihomed mobile networks. Existing schemes that make use of the aggregated bandwidth of multiple paths can overcome bandwidth limitations on a single path but suffer an efficiency penalty caused by retransmission of lost packets in reliable transport schemes or path switching overheads in unreliable transport schemes. This work focuses on the evaluation of schemes to permit concurrent use of multiple paths to deliver video streams. A comprehensive streaming framework for concurrent multipath video streaming is proposed and experimentally evaluated, using current state-of-the-art H.264 Scalable Video Coding (H.264/SVC and the next generation High Efficiency Video Coding (HEVC standards. It provides a valuable insight into the benefit of using such schemes in conjunction with encoder specific packet prioritisation mechanisms for quality-aware packet scheduling and scalable streaming. The remaining obstacles to deployment of concurrent multipath schemes are identified, and the challenges in realising HEVC based concurrent multipath streaming are highlighted.

  8. Real-time video streaming using H.264 scalable video coding (SVC) in multihomed mobile networks: a testbed approach

    Science.gov (United States)

    Nightingale, James; Wang, Qi; Grecos, Christos

    2011-03-01

    Users of the next generation wireless paradigm known as multihomed mobile networks expect satisfactory quality of service (QoS) when accessing streamed multimedia content. The recent H.264 Scalable Video Coding (SVC) extension to the Advanced Video Coding standard (AVC), offers the facility to adapt real-time video streams in response to the dynamic conditions of multiple network paths encountered in multihomed wireless mobile networks. Nevertheless, preexisting streaming algorithms were mainly proposed for AVC delivery over multipath wired networks and were evaluated by software simulation. This paper introduces a practical, hardware-based testbed upon which we implement and evaluate real-time H.264 SVC streaming algorithms in a realistic multihomed wireless mobile networks environment. We propose an optimised streaming algorithm with multi-fold technical contributions. Firstly, we extended the AVC packet prioritisation schemes to reflect the three-dimensional granularity of SVC. Secondly, we designed a mechanism for evaluating the effects of different streamer 'read ahead window' sizes on real-time performance. Thirdly, we took account of the previously unconsidered path switching and mobile networks tunnelling overheads encountered in real-world deployments. Finally, we implemented a path condition monitoring and reporting scheme to facilitate the intelligent path switching. The proposed system has been experimentally shown to offer a significant improvement in PSNR of the received stream compared with representative existing algorithms.

  9. Discrete LQ Rate Control for MPEG2 Video Streaming System

    National Research Council Canada - National Science Library

    Xiaofei Zhou; Kenneth Ong

    2008-01-01

    ...) to transmissions of MPEG2 streams in IP networks. We give out the detail deduction for disturbed-DLQ-regulator problem and the corresponding methods to implement the results into media streaming rate control...

  10. Some Aspects of Testing Process for Transport Streams in Digital Video Broadcasting

    CERN Document Server

    Arsinte, Radu

    2008-01-01

    This paper presents some aspects related to the DVB (Digital Video Broadcasting) investigation. The basic aspects of DVB are presented, with an emphasis on DVB-T version of standard. The main purpose of this research is to analyze the way that the transmission of the transport streams is realized in case of the Terrestrial Digital Video Broadcasting (DVB-T). To accomplish this, first, Digital Video Broadcasting standard is presented, and then the main aspects of DVB testing and analysis of the transport streams are investigated. The paper presents also the results obtained using two programs designed for DVB analysis: Mosalina and TSA.

  11. Experimental comparison of methods for estimation of the observed velocity of the vehicle in video stream

    Science.gov (United States)

    Konovalenko, Ivan; Kuznetsova, Elena

    2015-02-01

    In this paper, we consider the problem of object's velocity estimation via video stream by comparing three new methods of velocity estimation named as vertical edge algorithm, modified Lucas-Kanade method, and feature points algorithm. As an applied example the task of automatic evaluation of vehicles' velocity via video stream on toll roads is chosen. We took some videos from cameras mounted on the toll roads and marked them out to determine true velocity. Comparison is carried out of performance in the correct velocity detection of the proposed methods with each other. The relevance of this paper is practical implementation of these methods overcoming all the difficulties of realization.

  12. A Simple FSPN Model of P2P Live Video Streaming System

    OpenAIRE

    Kotevski, Zoran; Mitrevski, Pece

    2011-01-01

    Peer to Peer (P2P) live streaming is relatively new paradigm that aims at streaming live video to large number of clients at low cost. Many such applications already exist in the market, but, prior to creating such system it is necessary to analyze its performance via representative model that can provide good insight in the system’s behavior. Modeling and performance analysis of P2P live video streaming systems is challenging task which requires addressing many properties and issues of P2P s...

  13. Streaming and congestion control using scalable video coding based on H.264/AVC

    Institute of Scientific and Technical Information of China (English)

    NGUYEN Dieu Thanh; OSTERMANN Joern

    2006-01-01

    This paper presents a streaming system using scalable video coding based on H.264/AVC. The system provides a congestion control algorithm supported by channel bandwidth estimation of the client. It uses retransmission only for packets of the base layer to disburden the congested network. The bandwidth estimation allows for adjusting the transmission rate quickly to the current available bandwidth of the network. Compared to binomial congestion control, the proposed system allows for shorter start-up times and data rate adaptation. The paper describes the components of this streaming system and the results of experiments showing that the proposed approach works effectively for streaming video.

  14. Multi Attribute Content Distribution and Replication Based Video Streaming in Wireless Networks for Qos Improvement

    Directory of Open Access Journals (Sweden)

    A. Balakrishnan

    2015-10-01

    Full Text Available The growth of information technology has introduced various functionalities and services to support video streaming like video streaming and live streaming. There are many approaches has been discussed to support content delivery in wireless networks, but suffers with the problem of latency and quality of streaming which takes more time and the frequency of retransmission is high. To solve these problems, we propose a multi attribute location selection and distribution approach to select the location from where the video content has to be fetched and based on the multi attribute replication scheme new copy of the video content will be replicated in more locations according to various factors of quality of service. The proposed method maintains number of replicas  of video content in different locations of wireless networks. The method selects the location of the video content or the node which has the requested data according to the delay present in the network and the user location. Also the number of replicas maintained is performed according to the spatial request factor which represents the number of request being received from different user from a specific spatial region and the other factors like delay, number of users and the traffic incurred in the network towards a video content. The proposed method reduces the overall latency present in the network and increases the efficiency of content delivery which supports multimedia data transfer. Also the proposed method reduces the overall time complexity and reduces the overhead introduced by data transfer.

  15. Rate-distortion optimized frame dropping and scheduling for multi-user conversational and streaming video

    Institute of Scientific and Technical Information of China (English)

    TU Wei; CHAKARESKI Jacob; STEINBACH Eckehard

    2006-01-01

    We propose a Rate-Distortion (RD) optimized strategy for frame-dropping and scheduling of multi-user conversational and streaming videos. We consider a scenario where conversational and streaming videos share the forwarding resources at a network node. Two buffers are setup on the node to temporarily store the packets for these two types of video applications. For streaming video, a big buffer is used as the associated delay constraint of the application is moderate and a very small buffer is used for conversational video to ensure that the forwarding delay of every packet is limited. A scheduler is located behind these two buffers that dynamically assigns transmission slots on the outgoing link to the two buffers. Rate-distortion side information is used to perform RD-optimized frame dropping in case of node overload. Sharing the data rate on the outgoing link between the conversational and the streaming videos is done either based on the fullness of the two associated buffers or on the mean incoming rates of the respective videos. Simulation results showed that our proposed RD-optimized frame dropping and scheduling approach provides significant improvements in performance over the popular priority-based random dropping (PRD) technique.

  16. Scalable Video Streaming Relay for Smart Mobile Devices in Wireless Networks.

    Science.gov (United States)

    Kwon, Dongwoo; Je, Huigwang; Kim, Hyeonwoo; Ju, Hongtaek; An, Donghyeok

    2016-01-01

    Recently, smart mobile devices and wireless communication technologies such as WiFi, third generation (3G), and long-term evolution (LTE) have been rapidly deployed. Many smart mobile device users can access the Internet wirelessly, which has increased mobile traffic. In 2014, more than half of the mobile traffic around the world was devoted to satisfying the increased demand for the video streaming. In this paper, we propose a scalable video streaming relay scheme. Because many collisions degrade the scalability of video streaming, we first separate networks to prevent excessive contention between devices. In addition, the member device controls the video download rate in order to adapt to video playback. If the data are sufficiently buffered, the member device stops the download. If not, it requests additional video data. We implemented apps to evaluate the proposed scheme and conducted experiments with smart mobile devices. The results showed that our scheme improves the scalability of video streaming in a wireless local area network (WLAN).

  17. Fine-Grained Rate Shaping for Video Streaming over Wireless Networks

    Directory of Open Access Journals (Sweden)

    Chen Tsuhan

    2004-01-01

    Full Text Available Video streaming over wireless networks faces challenges of time-varying packet loss rate and fluctuating bandwidth. In this paper, we focus on streaming precoded video that is both source and channel coded. Dynamic rate shaping has been proposed to “shape” the precompressed video to adapt to the fluctuating bandwidth. In our earlier work, rate shaping was extended to shape the channel coded precompressed video, and to take into account the time-varying packet loss rate as well as the fluctuating bandwidth of the wireless networks. However, prior work on rate shaping can only adjust the rate oarsely. In this paper, we propose “fine-grained rate shaping (FGRS” to allow for bandwidth adaptation over a wide range of bandwidth and packet loss rate in fine granularities. The video is precoded with fine granularity scalability (FGS followed by channel coding. Utilizing the fine granularity property of FGS and channel coding, FGRS selectively drops part of the precoded video and still yields decodable bit-stream at the decoder. Moreover, FGRS optimizes video streaming rather than achieves heuristic objectives as conventional methods. A two-stage rate-distortion (RD optimization algorithm is proposed for FGRS. Promising results of FGRS are shown.

  18. For Video Streaming/Delivery: Is HTML5 the Real Fix?

    Directory of Open Access Journals (Sweden)

    John Millard

    2013-10-01

    Full Text Available The general movement towards streaming or playing videos on the web has grown exponentially in the last decade. The combination of new streaming technologies and faster Internet connections continue to provide enhanced and robust user experience for video content. For many organizations, adding videos on their websites has transitioned from a “cool” feature to a mission critical service. Some of the benefits in putting videos online include: to engage and convert visitors, to raise awareness or drive interest, to share inspirational stories or recent unique events, etc. Along with the growth in the use and need for video content on the web; delivering videos online also remains a messy activity for developers and web teams. Examples of existing challenges include creating more accessible videos with captions and delivering content (using adaptive streaming for the diverse range of mobile and tablet devices. In this article, we report on the decision-making and early results in using the Kaltura video platform in two popular library platforms: CONTENTdm and DSpace.

  19. Uncoordinated Multi-user Video Streaming in VANETs using Skype

    DEFF Research Database (Denmark)

    Belyaev, Evgeny; Moreschini, Sergio; Vinel, Alexey

    2017-01-01

    Real-time video delivery in Vehicle-to-Infrastructure (V2I) scenario enables a variety of multimedia vehicular services. We conduct experiments with Dedicated Short Range Communications (DSRC) transceivers located in the mutual proximity and exchanging Skype video calls traffic. We demonstrate th...

  20. SVC VIDEO STREAM ALLOCATION AND ADAPTATION IN HETEROGENEOUS NETWORK

    Directory of Open Access Journals (Sweden)

    E. A. Pakulova

    2016-07-01

    Full Text Available The paper deals with video data transmission in format H.264/SVC standard with QoS requirements satisfaction. The Sender-Side Path Scheduling (SSPS algorithm and Sender-Side Video Adaptation (SSVA algorithm were developed. SSPS algorithm gives the possibility to allocate video traffic among several interfaces while SSVA algorithm dynamically changes the quality of video sequence in relation to QoS requirements. It was shown that common usage of two developed algorithms enables to aggregate throughput of access networks, increase parameters of Quality of Experience and decrease losses in comparison with Round Robin algorithm. For evaluation of proposed solution, the set-up was made. The trace files with throughput of existing public networks were used in experiments. Based on this information the throughputs of networks were limited and losses for paths were set. The results of research may be used for study and transmission of video data in heterogeneous wireless networks.

  1. An Introduction to Recording, Editing, and Streaming Picture-in-Picture Ultrasound Videos.

    Science.gov (United States)

    Rajasekaran, Sathish; Hall, Mederic M; Finnoff, Jonathan T

    2016-08-01

    This paper describes the process by which high-definition resolution (up to 1920 × 1080 pixels) ultrasound video can be captured in conjunction with high-definition video of the transducer position (picture-in-picture). In addition, we describe how to edit the recorded video feeds to combine both feeds, and to crop, resize, split, stitch, cut, annotate videos, and also change the frame rate, insert pictures, edit the audio feed, and use chroma keying. We also describe how to stream a picture-in-picture ultrasound feed during a videoconference. Copyright © 2016 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

  2. Scalable Video Streaming Traffic Delivery in IP/UMTS Networking Environments

    Directory of Open Access Journals (Sweden)

    Thomas Pliakas

    2007-04-01

    Full Text Available The paper discusses the end-to-end QoS provisioning for scalable video streaming traffic delivery over heterogeneous IP/UMTS networks. A prototype architecture is proposed, and is further validated, that explores the joint use of packet prioritization and scalable video coding (SVC together with the appropriate mapping of UMTS traffic classes to the DiffServ traffic classes. A complete set of simulation scenarios, involving eight different video sequences and using two different scalable encoders, demonstrates the quality gains of both scalable video coding and prioritized packetization.

  3. The effects of a bike active video game on players' physical activity and motivation

    Institute of Scientific and Technical Information of China (English)

    Denis Pasco; Cédric Roure; Gilles Kermarrec; Zachary Pope; Zan Gao

    2017-01-01

    Background:Players may not acquire adequate levels of moderate-to-vigorous physical activity (MVPA) when playing commercial video games.This study's goal was to evaluate the effects of an exercise bike video game played by using a mobile application-based exergame that was designed exclusively to promote participants' MVPA,with additional attention paid to this game's ability to promote greater situational interest.Methods:An experimental design was used with 163 students (aged 20.31 ± 1.30,18-26 years,61.3% male),all of whom were randomly allocated into an experimental group and a control group.Physical activity (PA) levels were assessed with ActiGraph GI3X+ (ActiGraph Inc.,Fort Walton Beach,FL,USA) accelerometers.The situational interest scale was used to evaluate students' situational interest in both groups.Multivariate analysis of variance was conducted to examine the differences between sedentary behavior,PA levels,and situational interest between groups.Regression analyses were also used,with the purpose being to evaluate the strength of the relationship between PA and situational interest.Results:Results revealed that the experimental group had higher degrees of sedentary behavior,light PA,total interest,instant enjoyment,exploration intention,attention demand,novelty,and challenge,whereas the control group received higher scores for MVPA (control 95.01% vs.experimental group 89.94%).Regression analysis indicated that instant enjoyment (β =0.49,p < 0.01),exploration intention (β =0.18,p < 0.05),and attention demand (β =0.17,p < 0.05) were positive predictors for total interest,explaining 43% of its variance.Conclusion:A newly designed mobile application-based exergame played via an exercise bike may enhance situational interest and provide a decent level of PA for players.

  4. Efficient streaming of stereoscopic depth-based 3D videos

    Science.gov (United States)

    Temel, Dogancan; Aabed, Mohammed; Solh, Mashhour; AlRegib, Ghaassan

    2013-02-01

    In this paper, we propose a method to extract depth from motion, texture and intensity. We first analyze the depth map to extract a set of depth cues. Then, based on these depth cues, we process the colored reference video, using texture, motion, luminance and chrominance content, to extract the depth map. The processing of each channel in the YCRCB-color space is conducted separately. We tested this approach on different video sequences with different monocular properties. The results of our simulations show that the extracted depth maps generate a 3D video with quality close to the video rendered using the ground truth depth map. We report objective results using 3VQM and subjective analysis via comparison of rendered images. Furthermore, we analyze the savings in bitrate as a consequence of eliminating the need for two video codecs, one for the reference color video and one for the depth map. In this case, only the depth cues are sent as a side information to the color video.

  5. Two-Stream Transformer Networks for Video-based Face Alignment.

    Science.gov (United States)

    Liu, Hao; Lu, Jiwen; Feng, Jianjiang; Zhou, Jie

    2017-08-01

    In this paper, we propose a two-stream transformer networks (TSTN) approach for video-based face alignment. Unlike conventional image-based face alignment approaches which cannot explicitly model the temporal dependency in videos and motivated by the fact that consistent movements of facial landmarks usually occur across consecutive frames, our TSTN aims to capture the complementary information of both the spatial appearance on still frames and the temporal consistency information across frames. To achieve this, we develop a two-stream architecture, which decomposes the video-based face alignment into spatial and temporal streams accordingly. Specifically, the spatial stream aims to transform the facial image to the landmark positions by preserving the holistic facial shape structure. Accordingly, the temporal stream encodes the video input as active appearance codes, where the temporal consistency information across frames is captured to help shape refinements. Experimental results on the benchmarking video-based face alignment datasets show very competitive performance of our method in comparisons to the state-of-the-arts.

  6. Peer-to-Peer Live Streaming and Video On Demand Design Issues and its Challenges

    CERN Document Server

    K, Hareesh

    2011-01-01

    Peer-to-Peer Live streaming and Video on Demand is the most popular media applications over the Internet in recent years. These systems reduce the load on the server and provide a scalable content distribution. A new paradigm of P2P network collaborates to build large distributed video applications on existing networks .But, the problem of designing the system are at par with the P2P media streaming, live and Video on demand systems. Hence a comprehensive design comparison is needed to build such kind of system architecture. Therefore, in this paper we elaborately studied the traditional approaches for P2P streaming architectures, and its critical design issues, as well as practicable challenges. Thus, our studies in this paper clearly point the tangible design issues and its challenges, and other intangible issues for providing P2P VoD services.

  7. Dynamic Programming Optimization of Multi-rate Multicast Video-Streaming Services

    Directory of Open Access Journals (Sweden)

    Nestor Michael Caños Tiglao

    2010-06-01

    Full Text Available In large scale IP Television (IPTV and Mobile TV distributions, the video signal is typically encoded and transmitted using several quality streams, over IP Multicast channels, to several groups of receivers, which are classified in terms of their reception rate. As the number of video streams is usually constrained by both the number of TV channels and the maximum capacity of the content distribution network, it is necessary to find the selection of video stream transmission rates that maximizes the overall user satisfaction. In order to efficiently solve this problem, this paper proposes the Dynamic Programming Multi-rate Optimization (DPMO algorithm. The latter was comparatively evaluated considering several user distributions, featuring different access rate patterns. The experimental results reveal that DPMO is significantly more efficient than exhaustive search, while presenting slightly higher execution times than the non-optimal Multi-rate Step Search (MSS algorithm.

  8. Toward 3D-IPTV: design and implementation of a stereoscopic and multiple-perspective video streaming system

    Science.gov (United States)

    Petrovic, Goran; Farin, Dirk; de With, Peter H. N.

    2008-02-01

    3D-Video systems allow a user to perceive depth in the viewed scene and to display the scene from arbitrary viewpoints interactively and on-demand. This paper presents a prototype implementation of a 3D-video streaming system using an IP network. The architecture of our streaming system is layered, where each information layer conveys a single coded video signal or coded scene-description data. We demonstrate the benefits of a layered architecture with two examples: (a) stereoscopic video streaming, (b) monoscopic video streaming with remote multiple-perspective rendering. Our implementation experiments confirm that prototyping 3D-video streaming systems is possible with today's software and hardware. Furthermore, our current operational prototype demonstrates that highly heterogeneous clients can coexist in the system, ranging from auto-stereoscopic 3D displays to resource-constrained mobile devices.

  9. A Complexity-Aware Video Adaptation Mechanism for Live Streaming Systems

    Science.gov (United States)

    Lu, Meng-Ting; Yao, Jason J.; Chen, Homer H.

    2007-12-01

    The paradigm shift of network design from performance-centric to constraint-centric has called for new signal processing techniques to deal with various aspects of resource-constrained communication and networking. In this paper, we consider the computational constraints of a multimedia communication system and propose a video adaptation mechanism for live video streaming of multiple channels. The video adaptation mechanism includes three salient features. First, it adjusts the computational resource of the streaming server block by block to provide a fine control of the encoding complexity. Second, as far as we know, it is the first mechanism to allocate the computational resource to multiple channels. Third, it utilizes a complexity-distortion model to determine the optimal coding parameter values to achieve global optimization. These techniques constitute the basic building blocks for a successful application of wireless and Internet video to digital home, surveillance, IPTV, and online games.

  10. A Complexity-Aware Video Adaptation Mechanism for Live Streaming Systems

    Directory of Open Access Journals (Sweden)

    Homer H. Chen

    2007-01-01

    Full Text Available The paradigm shift of network design from performance-centric to constraint-centric has called for new signal processing techniques to deal with various aspects of resource-constrained communication and networking. In this paper, we consider the computational constraints of a multimedia communication system and propose a video adaptation mechanism for live video streaming of multiple channels. The video adaptation mechanism includes three salient features. First, it adjusts the computational resource of the streaming server block by block to provide a fine control of the encoding complexity. Second, as far as we know, it is the first mechanism to allocate the computational resource to multiple channels. Third, it utilizes a complexity-distortion model to determine the optimal coding parameter values to achieve global optimization. These techniques constitute the basic building blocks for a successful application of wireless and Internet video to digital home, surveillance, IPTV, and online games.

  11. Using the Periscope Live Video-Streaming Application for Global Pathology Education: A Brief Introduction.

    Science.gov (United States)

    Fuller, Maren Y; Mukhopadhyay, Sanjay; Gardner, Jerad M

    2016-07-21

    Periscope is a live video-streaming smartphone application (app) that allows any individual with a smartphone to broadcast live video simultaneously to multiple smartphone users around the world. The aim of this review is to describe the potential of this emerging technology for global pathology education. To our knowledge, since the launch of the Periscope app (2015), only a handful of educational presentations by pathologists have been streamed as live video via Periscope. This review includes links to these initial attempts, a step-by-step guide for those interested in using the app for pathology education, and a summary of the pros and cons, including ethical/legal issues. We hope that pathologists will appreciate the potential of Periscope for sharing their knowledge, expertise, and research with a live (and potentially large) audience without the barriers associated with traditional video equipment and standard classroom/conference settings.

  12. Content-Adaptive Packetization and Streaming of Wavelet Video over IP Networks

    Directory of Open Access Journals (Sweden)

    Chien-Peng Ho

    2007-03-01

    Full Text Available This paper presents a framework of content-adaptive packetization scheme for streaming of 3D wavelet-based video content over lossy IP networks. The tradeoff between rate and distortion is controlled by jointly adapting scalable source coding rate and level of forward error correction (FEC protection. A content dependent packetization mechanism with data-interleaving and Reed-Solomon protection for wavelet-based video codecs is proposed to provide unequal error protection. This paper also tries to answer an important question for scalable video streaming systems: given extra bandwidth, should one increase the level of channel protection for the most important packets, or transmit more scalable source data? Experimental results show that the proposed framework achieves good balance between quality of the received video and level of error protection under bandwidth-varying lossy IP networks.

  13. Accessing and engaging with video streams for educational purposes: experiences, issues and concerns

    Directory of Open Access Journals (Sweden)

    Maggie Bracher

    2005-12-01

    Full Text Available Video streaming has the potential to offer tutors a more flexible and accessible means of incorporating moving images into learning resources for their students than conventional video. Consideration is given to this assertion by drawing upon the experiences of staff and evidence from students at the University of Southampton in the use of a video, Back Care for Health Professionals, before and after it was streamed. The resulting case study highlights various issues and concerns, both logistical and pedagogic. These include ease of access, the form and frequency of guidance with respect to technical matters, the use of multiple channels of communication to convey key messages about the availability and value of the video, and the provision of demonstrations or ‘tasters'. In other words, what some might regard as the ‘softer' aspects of technological developments should receive at least as much attention as the ‘harder'.

  14. Temporal Error Concealment Technique for MPEG-4 Video Streams

    Institute of Scientific and Technical Information of China (English)

    DING Xuewen; YANG Zhaoxuan; GUO Yingchun

    2006-01-01

    Concerning inter4v mode employed widely in MPEG-4 video, a new temporal error concealment scheme for MPEG-4 video sequences is proposed, which can selectively interpolate one or four motion vectors (MVs) for the missing macroblock (MB) according to the estimated MB coding mode. Performance of the proposed scheme is compared with the existing schemes with multiple testing sequences at different bit error rates. Experimental results show that the proposed algorithm can mask the impairments caused by transmission errors more efficiently than 0 MV and average MV methods by consuming more time for different bit error rates. It has an acceptable image quality close to that obtained by the selective motion vector matching (SMVM) algorithm, while tak ing less than half of cycles of operations. The proposed concealment scheme is suitable for low complexity video real-time implementations.

  15. Cross Layer Design for Video Streaming in MANETs

    Directory of Open Access Journals (Sweden)

    George Adam

    2014-02-01

    Full Text Available Mobile Ad hoc NETworks (MANETs are becoming more essential to wireless communications due to growing popularity of mobile devices. However, MANETs do not seem to effectively support multimedia applications and especially video transmission. In this work, we propose a cross-layer design that aims to improve the performance of video transmission using TCP Friendly Rate Control (TFRC. Our design provides priority to video packets and exploits information from the MAC layer in order to improve TFRC’s performance. The proposed cross-layer design utilizes SNR measurements along the routing path, in order to make the route reconstruction procedure more efficient. Simulation results show that both the use of traffic classification and the SNR utilization lead to important improvements in terms of end-to-end Quality of Service (QoS

  16. Enhancing the Dialogue in Simultaneous Class-Based and Live Video-Streamed Teaching

    DEFF Research Database (Denmark)

    Jelsbak, Vibe Alopaeus; Ørngreen, Rikke; Thorsen, Jonas;

    2015-01-01

    teaching. This paper describes a work-in-progress project focused on developing possibilities for a more dialogue-based approach to live video-streamed teaching. We present our new setup and argue for educational designs which this is believed to support, and we outline the research design for collecting...... from home via the Internet. In live video-streamed teaching classes teachers tend to choose one-way communication instead of dialogue. We know from our early findings that technology issues are one of the main reasons for this, since the same teachers use dialogue and discussions in traditional...

  17. 基于Authorware实现WMV数字视频的播放控制%The Implementation of Controling the WMV Digital Video Player Based on Authorware

    Institute of Scientific and Technical Information of China (English)

    刘智浓; 张永利; 童子方

    2016-01-01

    WMV, regarded as one of the Microsoft Corporation's recommended products, is a sort of file compression format in streaming media digital video. It's been widely using in simulation, virtual reality, CAI and other multimedia technology. Case design shows that in Authorware, with the controls of Windows Media Player based on ActiveX control, we can make the WMV digital video playing personalized become true as well make the video playing smoothly and the programs running steadily by setting control properties.%WMV作为微软主推的一种流媒体数字视频文件压缩格式,在模拟仿真、虚拟现实和CAI等多媒体技术领域得到广泛的应用。实例设计表明,在Authorware中通过设置ActiveX控件Windows Media Player的属性,响应控件事件或调用控件方法等方式,在保证视频播放流畅性和程序运行稳定性的同时,可实现WMV数字视频的个性化播放控制。

  18. Simultaneous Class-based and Live Video Streamed Teaching

    DEFF Research Database (Denmark)

    Ørngreen, Rikke; Levinsen, Karin Ellen Tweddell; Jelsbak, Vibe Alopaeus

    2015-01-01

    The Bachelor Programme in Biomedical Laboratory Analysis at VIA's healthcare university college in Aarhus has established a blended class which combines traditional and live broadcast teaching (via an innovative choice of video conferencing system). On the so-called net-days, students have...... ensuring the anchoring of the project. Data was collected through video recordings, "the question of the day" to the students, focus group interviews with the teachers and a Pedagogical Day workshop. The analysis focuses on the experience gathered as seen in relation to four quadrants of study activities...

  19. Joint routing and rate allocation for multiple video streams in ad-hoc wireless networks

    Institute of Scientific and Technical Information of China (English)

    ZHU Xiao-qing; SINGH Jatinder Pal; GIROD Bernd

    2006-01-01

    The support for multiple video streams in an ad-hoc wireless network requires appropriate routing and rate allocation measures ascertaining the set of links for transmitting each stream and the encoding rate of the video to be delivered over the chosen links. The routing and rate allocation procedures impact the sustained quality of each video stream measured as the mean squared error (MSE) distortion at the receiver, and the overall network congestion in terms of queuing delay per link. We study the trade-off between these two competing objectives in a convex optimization formulation, and discuss both centralized and distributed solutions for joint routing and rate allocation for multiple streams. For each stream, the optimal allocated rate strikes a balance between the selfish motive of minimizing video distortion and the global good of minimizing network congestions, while the routes are chosen over the least-congested links in the network. In addition to detailed analysis, network simulation results using ns-2 are presented for studying the optimal choice of parameters and to confirm the effectiveness of the proposed measures.

  20. Optimal Multi-Interface Selection for Mobile Video Streaming in Efficient Battery Consumption and Data Usage

    Directory of Open Access Journals (Sweden)

    Seonghoon Moon

    2016-01-01

    Full Text Available With the proliferation of high-performance, large-screen mobile devices, users’ expectations of having access to high-resolution video content in smooth network environments are steadily growing. To guarantee such stable streaming, a high cellular network bandwidth is required; yet network providers often charge high prices for even limited data plans. Moreover, the costs of smoothly streaming high-resolution videos are not merely monetary; the device’s battery life must also be accounted for. To resolve these problems, we design an optimal multi-interface selection system for streaming video over HTTP/TCP. An optimization problem including battery life and LTE data constraints is derived and then solved using binary integer programming. Additionally, the system is designed with an adoption of split-layer scalable video coding, which provides direct adaptations of video quality and prevents out-of-order packet delivery problems. The proposed system is evaluated using a prototype application in a real, iOS-based device as well as through experiments conducted in heterogeneous mobile scenarios. Results show that the system not only guarantees the highest-possible video quality, but also prevents reckless consumption of LTE data and battery life.

  1. Streaming video to enhance students’ reflection in dance education

    NARCIS (Netherlands)

    Leijen, A.; Lam, I.; Wildschut, L.; Simons, P.R.J.; Admiraal, W.

    2009-01-01

    This paper presents an evaluation case study that describes the experiences of 15 students and 2 teachers using a video-based learning environment, DiViDU, to facilitate students’ daily reflection activities in a composition course and a ballet course. To support dance students’ reflection processes

  2. Streaming video to enhance students’ reflection in dance education

    NARCIS (Netherlands)

    Leijen, A.; Lam, I.; Wildschut, L.; Simons, P.R.J.; Admiraal, W.

    2009-01-01

    This paper presents an evaluation case study that describes the experiences of 15 students and 2 teachers using a video-based learning environment, DiViDU, to facilitate students’ daily reflection activities in a composition course and a ballet course. To support dance students’ reflection processes

  3. Low Delay Video Streaming on the Internet of Things Using Raspberry Pi

    Directory of Open Access Journals (Sweden)

    Ulf Jennehag

    2016-09-01

    Full Text Available The Internet of Things is predicted to consist of over 50 billion devices aiming to solve problems in most areas of our digital society. A large part of the data communicated is expected to consist of various multimedia contents, such as live audio and video. This article presents a solution for the communication of high definition video in low-delay scenarios (<200 ms under the constraints of devices with limited hardware resources, such as the Raspberry Pi. We verify that it is possible to enable low delay video streaming between Raspberry Pi devices using a distributed Internet of Things system called the SensibleThings platform. Specifically, our implementation transfers a 6 Mbps H.264 video stream of 1280 × 720 pixels at 25 frames per second between devices with a total delay of 181 ms on the public Internet, of which the overhead of the distributed Internet of Things communication platform only accounts for 18 ms of this delay. We have found that the most significant bottleneck of video transfer on limited Internet of Things devices is the video coding and not the distributed communication platform, since the video coding accounts for 90% of the total delay.

  4. A time-varying subjective quality model for mobile streaming videos with stalling events

    Science.gov (United States)

    Ghadiyaram, Deepti; Pan, Janice; Bovik, Alan C.

    2015-09-01

    Over-the-top mobile video streaming is invariably influenced by volatile network conditions which cause playback interruptions (stalling events), thereby impairing users' quality of experience (QoE). Developing models that can accurately predict users' QoE could enable the more efficient design of quality-control protocols for video streaming networks that reduce network operational costs while still delivering high-quality video content to the customers. Existing objective models that predict QoE are based on global video features, such as the number of stall events and their lengths, and are trained and validated on a small pool of ad hoc video datasets, most of which are not publicly available. The model we propose in this work goes beyond previous models as it also accounts for the fundamental effect that a viewer's recent level of satisfaction or dissatisfaction has on their overall viewing experience. In other words, the proposed model accounts for and adapts to the recency, or hysteresis effect caused by a stall event in addition to accounting for the lengths, frequency of occurrence, and the positions of stall events - factors that interact in a complex way to affect a user's QoE. On the recently introduced LIVE-Avvasi Mobile Video Database, which consists of 180 distorted videos of varied content that are afflicted solely with over 25 unique realistic stalling events, we trained and validated our model to accurately predict the QoE, attaining standout QoE prediction performance.

  5. 基于ARM处理器的流媒体播放器客户端的构建%A building of streaming player client cased on ARM processor

    Institute of Scientific and Technical Information of China (English)

    慈文彦; 何君; 朱明祥

    2012-01-01

    A new type of embedded streaming media client is designed in this paper. It takes the ARM processor and embedded Linux operating system as platform, and develops an embedded streaming player which broadcasts in real time streaming on the ARM through the RTP/RTSP extensions and transplantation of the original Mplayer. This player not only inherits advantages of the Mplayer such as supporting multiple media formats and extensive post-processing filters, but also carries out streaming media smoothly even on the Samsung S3C2410 ARM board whose main frequency is only 200M. What' s more, the video streaming runs like floating clouds and the pictures look like seeing from the mirrors, which makes the feeling that the video is just from the original machine, so this player fits the embedded system very well.%设计了一种新型的嵌入式流媒体的客户端.它以ARM处理器和Linux嵌入式操作系统为平台,通过对原有Mplayer播放器进行RTP/RTSP功能扩展和移植,开发出了一款在ARM开发板上进行实时流播放的嵌入式流媒体播放器.这种播放器不但继承了Mplayer支持多种媒体格式以及丰富的后期处理滤镜等优点,而且即使在主频仅为200M的三星S3C2410 ARM开发板上也能够进行顺畅的流媒体播放,视频流顺畅,画质清晰,给人的感觉如同视频出自本机一般,非常适合应用于嵌入式系统.

  6. Content-Based Video Quality Prediction for MPEG4 Video Streaming over Wireless Networks

    Directory of Open Access Journals (Sweden)

    Asiya Khan

    2009-08-01

    Full Text Available There are many parameters that affect video quality but their combined effect is not well identified and understood when video is transmitted over mobile/ wireless networks. In addition, video content has an impact on video quality under same network conditions. The main aim of this paper is the prediction of video quality combining the application and network level parameters for all content types. Firstly, video sequences are classified into groups representing different content types using cluster analysis. The classification of contents is based on the temporal (movement and spatial (edges, brightness feature extraction. Second, to study and analyze the behaviour of video quality for wide range variations of a set of selected parameters. Finally, to develop two learning models based on – (1 ANFIS to estimate the visual perceptual quality in terms of the Mean Opinion Score (MOS and decodable frame rate (Q value and (2 regression modeling to estimate the visual perceptual quality in terms of the MOS. We trained three ANFIS-based ANNs and regression based- models for the three distinct content types using a combination of network and application level parameters and tested the two models using unseen dataset. We confirmed that the video quality is more sensitive to network level compared to application level parameters. Preliminary results show that a good prediction accuracy was obtained from both models. However, the regression based model performed better in terms of the correlation coefficient and the root mean squared error. The work should help in the development of a reference-free video prediction model and Quality of Service (QoS control methods for video over wireless/mobile networks.

  7. Simultaneous Class-based and Live Video Streamed Teaching

    DEFF Research Database (Denmark)

    Ørngreen, Rikke; Levinsen, Karin Ellen Tweddell; Jelsbak, Vibe Alopaeus

    2015-01-01

    The Bachelor Programme in Biomedical Laboratory Analysis at VIA's healthcare university college in Aarhus has established a blended class which combines traditional and live broadcast teaching (via an innovative choice of video conferencing system). On the so-called net-days, students have...... the choice of either attending teaching sessions in the traditional way or working from home via the Internet. The education was motivated to expand the use of technologysupported teaching, by offering a flexible study programme, thereby increasing the recruitment base. The analysis described in this article...... ensuring the anchoring of the project. Data was collected through video recordings, "the question of the day" to the students, focus group interviews with the teachers and a Pedagogical Day workshop. The analysis focuses on the experience gathered as seen in relation to four quadrants of study activities...

  8. Online Detection of Abnormal Events in Video Streams

    Directory of Open Access Journals (Sweden)

    Tian Wang

    2013-01-01

    an image descriptor and online nonlinear classification method. We introduce the covariance matrix of the optical flow and image intensity as a descriptor encoding moving information. The nonlinear online support vector machine (SVM firstly learns a limited set of the training frames to provide a basic reference model then updates the model and detects abnormal events in the current frame. We finally apply the method to detect abnormal events on a benchmark video surveillance dataset to demonstrate the effectiveness of the proposed technique.

  9. Parity Bit Replenishment for JPEG 2000-Based Video Streaming

    Directory of Open Access Journals (Sweden)

    François-Olivier Devaux

    2009-01-01

    Full Text Available This paper envisions coding with side information to design a highly scalable video codec. To achieve fine-grained scalability in terms of resolution, quality, and spatial access as well as temporal access to individual frames, the JPEG 2000 coding algorithm has been considered as the reference algorithm to encode INTRA information, and coding with side information has been envisioned to refresh the blocks that change between two consecutive images of a video sequence. One advantage of coding with side information compared to conventional closed-loop hybrid video coding schemes lies in the fact that parity bits are designed to correct stochastic errors and not to encode deterministic prediction errors. This enables the codec to support some desynchronization between the encoder and the decoder, which is particularly helpful to adapt on the fly pre-encoded content to fluctuating network resources and/or user preferences in terms of regions of interest. Regarding the coding scheme itself, to preserve both quality scalability and compliance to the JPEG 2000 wavelet representation, a particular attention has been devoted to the definition of a practical coding framework able to exploit not only the temporal but also spatial correlation among wavelet subbands coefficients, while computing the parity bits on subsets of wavelet bit-planes. Simulations have shown that compared to pure INTRA-based conditional replenishment solutions, the addition of the parity bits option decreases the transmission cost in terms of bandwidth, while preserving access flexibility.

  10. Network-adaptive HD MPEG-2 video streaming with cross-layered channel monitoring in WLAN

    Institute of Scientific and Technical Information of China (English)

    PARK Sanghoon; YOON Hayoung; KIM Jongwon

    2006-01-01

    In this paper, we propose a practical design and implementation of network-adaptive high definition (HD) MPEG-2video streaming combined with cross-layered channel monitoring (CLM) over the IEEE 802.1 la wireless local area network (WLAN). For wireless channel monitoring, we adopt a cross-layered approach, where an access point (AP) periodically measures lower layers such as medium access control (MAC) and physical (PHY) transmission information (e.g., MAC layer loss rate) and then sends the monitored information to the streaming server application. The adaptive streaming server with the CLM scheme reacts more quickly and efficiently to the fluctuating wireless channel than the end-to-end application-layer monitoring (E2EM)scheme. The streaming server dynamically performs priority-based frame dropping to adjust the sending rate according to the measured wireless channel condition. For this purpose, the proposed streaming system nicely provides frame-based prioritized packetization by using a real-time stream parsing module. Various evaluation results over an IEEE 802.1 la WLAN testbed are provided to verify the intended Quality of Service (QoS) adaptation capability. Experimental results showed that the proposed system can mitigate the quality degradation of video streaming due to the fluctuations of time-varying channel.

  11. Using Text Mining to Uncover Students' Technology-Related Problems in Live Video Streaming

    Science.gov (United States)

    Abdous, M'hammed; He, Wu

    2011-01-01

    Because of their capacity to sift through large amounts of data, text mining and data mining are enabling higher education institutions to reveal valuable patterns in students' learning behaviours without having to resort to traditional survey methods. In an effort to uncover live video streaming (LVS) students' technology related-problems and to…

  12. Capabilities of Raspberry Pi 2 for Big Data and Video Streaming Applications in Data Centres

    NARCIS (Netherlands)

    Schot, Nick J.; Velthuis, Paul J.E.; Postema, Björn Frits; Remke, Anne Katharina Ingrid; Remke, A.K.I.; Haverkort, Boudewijn R.H.M.; Haverkort, B.R.H.M.

    Many new data centres have been built in recent years in order to keep up with the rising demand for server capacity. These data centres require a lot of electrical energy and cooling. Big data and video streaming are two heavily used applications in data centres. This paper experimentally

  13. Capabilities of Raspberry Pi 2 for Big Data and Video Streaming Applications in Data Centres

    NARCIS (Netherlands)

    Schot, Nick J.; Velthuis, Paul J.E.; Postema, Björn F.; Remke, A.K.I.; Haverkort, B.R.H.M.

    2016-01-01

    Many new data centres have been built in recent years in order to keep up with the rising demand for server capacity. These data centres require a lot of electrical energy and cooling. Big data and video streaming are two heavily used applications in data centres. This paper experimentally investiga

  14. Capabilities of Raspberry Pi 2 for Big Data and Video Streaming Applications in Data Centres

    NARCIS (Netherlands)

    Schot, Nick J.; Velthuis, Paul J.E.; Postema, Björn Frits; Remke, Anne Katharina Ingrid; Remke, A.K.I.; Haverkort, Boudewijn R.H.M.; Haverkort, B.R.H.M.

    2016-01-01

    Many new data centres have been built in recent years in order to keep up with the rising demand for server capacity. These data centres require a lot of electrical energy and cooling. Big data and video streaming are two heavily used applications in data centres. This paper experimentally investiga

  15. Constructing a Streaming Video-Based Learning Forum for Collaborative Learning

    Science.gov (United States)

    Chang, Chih-Kai

    2004-01-01

    As web-based courses using videos have become popular in recent years, the issue of managing audio-visual aids has become pertinent. Generally, the contents of audio-visual aids may include a lecture, an interview, a report, or an experiment, which may be transformed into a streaming format capable of making the quality of Internet-based videos…

  16. The EduPop: Improving Streaming Video for an Electronic Community.

    Science.gov (United States)

    Daugherty, Hubert; Cohn, Julie; Gorry, G. Anthony

    2003-01-01

    Provides examples of the need for enhanced streaming video in the greater Houston area, discussing how the EduPop router architecture meets this need by acting as a bridge for academic and commercial entities in the area. Catalogues the technological, organizational, and political challenges faced in implementing this architecture, offering a…

  17. Wireless live streaming video of laparoscopic surgery: a bandwidth analysis for handheld computers.

    Science.gov (United States)

    Gandsas, Alex; McIntire, Katherine; George, Ivan M; Witzke, Wayne; Hoskins, James D; Park, Adrian

    2002-01-01

    Over the last six years, streaming media has emerged as a powerful tool for delivering multimedia content over networks. Concurrently, wireless technology has evolved, freeing users from desktop boundaries and wired infrastructures. At the University of Kentucky Medical Center, we have integrated these technologies to develop a system that can wirelessly transmit live surgery from the operating room to a handheld computer. This study establishes the feasibility of using our system to view surgeries and describes the effect of bandwidth on image quality. A live laparoscopic ventral hernia repair was transmitted to a single handheld computer using five encoding speeds at a constant frame rate, and the quality of the resulting streaming images was evaluated. No video images were rendered when video data were encoded at 28.8 kilobytes per second (Kbps), the slowest encoding bitrate studied. The highest quality images were rendered at encoding speeds greater than or equal to 150 Kbps. Of note, a 15 second transmission delay was experienced using all four encoding schemes that rendered video images. We believe that the wireless transmission of streaming video to handheld computers has tremendous potential to enhance surgical education. For medical students and residents, the ability to view live surgeries, lectures, courses and seminars on handheld computers means a larger number of learning opportunities. In addition, we envision that wireless enabled devices may be used to telemonitor surgical procedures. However, bandwidth availability and streaming delay are major issues that must be addressed before wireless telementoring becomes a reality.

  18. Using Text Mining to Uncover Students' Technology-Related Problems in Live Video Streaming

    Science.gov (United States)

    Abdous, M'hammed; He, Wu

    2011-01-01

    Because of their capacity to sift through large amounts of data, text mining and data mining are enabling higher education institutions to reveal valuable patterns in students' learning behaviours without having to resort to traditional survey methods. In an effort to uncover live video streaming (LVS) students' technology related-problems and to…

  19. Quality of Service dengan Metode Differentiated Service untuk Layanan Video Streaming Jaringan UMTS

    Directory of Open Access Journals (Sweden)

    Putra Adi Wibowo

    2014-06-01

    Full Text Available Video streaming merupakan salah satu layanan aplikasi multimedia real time yang tersedia pada jaringan Universal Mobile Telecomunication System (UMTS. Banyaknya layanan telekomunikasi yang dapat dilayani UMTS tidak sebanding dengan bandwidth yang disediakan. Salah satu metode yang digunakan untuk meningkatkan kualitas layanan video streaming pada jaringan UMTS adalah dengan menerapkan metode antrian Differented Service (DiffServ. DiffServ menyediakan pembedaan layanan, dengan membagi trafik atas kelas-kelas, dan memperlakukan setiap kelas secara berbeda. Untuk mengetahui pengaruh penerapan metode antrian DiffServ pada layanan video streaming jaringan UMTS terhadap variasi trafik 25%, 50% dan 75% dengan simulasi jaringan OPNET Simulator 14.5. Metode antrian DiffServ yang digunakan adalah Priority Queuing (PQ, Weighted Fair Queuing (WFQ dan Modified Weighted Round Robin (MWRR. Parameter kualitas layanan yang digunakan adalah jitter, end-to-end delay dan packet loss. Dari hasil analisis diperoleh bahwa penerapan metode DiffServ pada variasi trafik adalah dapat meningkatkan kualitas layanan video streaming pada jaringan UMTS. Untuk penerapan metode antrian PQ, WFQ dan MWRR menghasilkan perbedaan nilai yang tidak jauh berbeda. Variasi trafik 50% memiliki kualitas layanan yang lebih baik dari pada variasi lainnya.

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

    Science.gov (United States)

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

    2016-08-01

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

  1. Distributed Spectrum Sharing for Video Streaming in Cognitive Radio Ad Hoc Networks

    Science.gov (United States)

    Ding, Lei; Pudlewski, Scott; Melodia, Tommaso; Batalama, Stella; Matyjas, John D.; Medley, Michael J.

    A distributed joint routing and spectrum sharing algorithm for video streaming applications over cognitive radio ad hoc networks is proposed in this article. The proposed cross-layer control scheme dynamically allocates routes, spectrum and power to maximize the network throughput under the constraints posed by delay-sensitive video applications. The algorithm evaluates the expected delay of competing flows in single-hop and two-hop networks considering the time-varying spectrum condition and occupancy, traffic characteristics, and the condition of queues at intermediate nodes. Simulation results show that the proposed algorithm significantly reduces the packet loss rate and improves the average peak signal-to-noise ratio (PSNR) of the received video streams.

  2. Intelligent Packet Shaper to Avoid Network Congestion for Improved Streaming Video Quality at Clients

    DEFF Research Database (Denmark)

    Kaul, Manohar; Khosla, Rajiv; Mitsukura, Y

    2003-01-01

    This paper proposes a traffic shaping algorithm based on neural networks, which adapts to a network over which streaming video is being transmitted. The purpose of this intelligent shaper is to eradicate all traffic congestion and improve the end-user's video quality. It possesses the capability...... to predict, to a very high level of accuracy, a state of congestion based upon the training data collected about the network behaviour. Initially, the current traffic shaping technologies are discussed and later a simulation in a controlled environment is illustrated to exhibit the effects...... of this intelligent traffic-shaping algorithm on the underlying network real time packet traffic and the eradication of unwanted abruption in the streaming video qualiy. This paper concluded from the end results of the simulation that neural networks are a very superior means of modeling real-time traffic...

  3. Design, Implementation and Evaluation of Congestion Control Mechanism for Video Streaming

    Directory of Open Access Journals (Sweden)

    Hiroshi Noborio

    2011-05-01

    Full Text Available In recent years, video streaming services over TCP, such as YouTube, have become more and more popular. TCP NewReno, the current TCP standard, performs greedy congestion control, which increases the congestion window size until packet loss occurs. Therefore, because TCP transmits data at a much higher rate than the video playback rate, the probability of packet loss in the network increases, which in turn takes bandwidth from other network traffic. In this paper, we propose a new transport-layer protocol, called TCP Stream, that solves the problem of TCP in video streaming. TCP Stream performs a hybrid congestion control that combines the loss-based congestion control, which uses packet loss as an index of congestion, and the delay-based congestion control, which uses delay as an index of congestion. Simulation and experimental results show that TCP Stream transmits data at the adjusted rate, unlike TCP NewReno, and does not steal bandwidth from of other network traffic.

  4. Head-Tail Video Streaming Over Peer To Peer Systems

    Directory of Open Access Journals (Sweden)

    Ali Sianati

    2011-03-01

    Full Text Available P2P systems similar to file sharing applications are being used vastly due to unrestricted nature of thesesystems. Their unrestricting comes from their ability to cooperate and aggregate peer’s resources andtheir scalability. On the other side, today technologies are traditional client-server applications. Theseapplications can perform strongly but they are not scalable due to limitations on server resources. Thislimitation of the client/server technology leads designers to use alternative technologies mainly P2P. Asa streaming system, P2P streaming network can be formed into two types, Tree-based and Mesh-based.In this paper a new mesh-based P2P system named Head-Tail streaming is proposed. Head-Tailsimplifies packet scheduling and node failure recovery by using paired-peer sending and node failureprediction. Our system outperforms ordinary systems comparing as delay and receive time. Our systemperforms better than ordinary systems based on two reasons :Overlapping sequence of chunks and nodereplacement policy.

  5. Real-Time Video Streaming in Multi-hop Wireless Static Ad Hoc Networks

    CERN Document Server

    Even, Guy; Medina, Moti; Shimon,; Shahar,; Zadorojniy, Alexander

    2011-01-01

    We deal with the problem of streaming multiple video streams between pairs of nodes in a multi-hop wireless ad hoc network. The nodes are positioned on a plane, know their locations, and are synchronized (via GPS). We consider a 802.11g WiFi network in which NICs can hop between non-overlapping frequency channels in a synchronous fashion. We design a centralized algorithm that computes a frequency assignment and a schedule whose goal is to maximize the minimum throughput over all the video streams. In addition, we developed a localized flow-control mechanism to stabilize the queue lengths. We simulated traffic scheduled by the algorithm using OMNET++/MixiM (i.e., physical SINR interference model with 802.11g) to test whether the computed throughput is achieved.

  6. Efficient bitstream switching for streaming of H.264/AVC coded video

    Directory of Open Access Journals (Sweden)

    Khan Ekram

    2011-01-01

    Full Text Available Abstract In this article, a novel scheme is proposed for switching among multiple bitrate video streams over Internet, to achieve best quality of service (QoS. The research is focused on selecting the best switching points inside the pre-coded variable bit rate video streams, to facilitate bandwidth scalability among the non-scalable multiple bitstreams. With a stepwise monotonically decreasing (downstairs bandwidth reservation scheme, it is shown that if switching occurs at the transition points in the "downstairs", then the best QoS can be achieved. However, insertion of switching pictures at these transition points may change the characteristics of the "downstairs" function and hence the bandwidth requirement. Here, we propose a scheme for proper management of the allocated resources to facilitate the stream switching in the "downstairs" through SP-frames. The performance is measured in terms of the wastage of bits in the receiver buffer and bandwidth utilization at the switching instances.

  7. The TSU Streaming Video Astronomy Course - II, Video Interface Design and Bandwidth Considerations

    Science.gov (United States)

    Burks, G. S.; Smith, W.

    2004-12-01

    Researchers are developing an on-line video astronomy course at Tennessee State University. Many factors are taken into account when designing a first year course for a broad audience. The initial target audience is students attending historically black colleges and universities, tribal colleges, and other minority institutions, without an astronomy course. The primary goal is to attract students into a course of study that could prepare them to enter the NASA workforce. A secondary goal is to serve the general student population. The question we try to address here is: How can we deliver the video components of such a course in a way that will take into account the innate learning styles of most students and the limited access to very high speed internet lines in smaller colleges? The design for the video information interface will be discussed. The effect of limited bandwidth on video size and other features of the presentation design is also analyzed.

  8. Simultaneous Class-based and Live Video Streamed Teaching

    DEFF Research Database (Denmark)

    Ørngreen, Rikke; Levinsen, Karin Ellen Tweddell; Jelsbak, Vibe Alopaeus;

    2015-01-01

    sheds light on the pedagogical challenges, the educational designs possible, the opportunities and constrains associated with video conferencing as a pedagogical practice, as well as the technological, structural and organisational conditions involved. In this paper a participatory action research...... project is presented. The objective of the project was to identify potentials and barriers from an ICT-supported learning perspective; to develop robust educational designs and teaching scenarios, and to qualify teaching staff in teaching activities which involve the use of the blended class model, thus...

  9. Effects of playing a violent video game as male versus female avatar on subsequent aggression in male and female players.

    Science.gov (United States)

    Yang, Grace S; Huesmann, L Rowell; Bushman, Brad J

    2014-01-01

    Previous research has shown that violent video games can increase aggression in players immediately after they play. The present research examines the effects of one subtle cue within violent video games that might moderate these effects-whether the avatar is male or female. One common stereotype is that males are more aggressive than females. Thus, playing a violent video game as a male avatar, compared to a female avatar, should be more likely to prime aggressive thoughts and inclinations in players and lead to more aggressive behavior afterwards. Male and female university students (N = 242) were randomly assigned to play a violent video game as a male or female avatar. After gameplay, participants gave an ostensible partner who hated spicy food hot sauce to eat. The amount of hot sauce given was used to measure aggression. Consistent with priming theory, results showed that both male and female participants who played a violent game as a male avatar behaved more aggressively afterwards than those who played as female avatar. The priming effects of the male avatar were somewhat stronger for male participants than for female participants, suggesting that male participants identified more with the male avatar than did the female participants. These results are particularly noteworthy because they are consistent with another recent experiment showing that playing a violent game as an avatar with a different stereotypically aggressive attribute (black skin color) stimulates more aggression than playing as an avatar without the stereotypically aggressive attribute (Yang et al., 2014, Social Psychological and Personality Science).

  10. Downlink Video Streaming for Users Non-Equidistant from Base Station

    Directory of Open Access Journals (Sweden)

    S. Pejoski

    2012-06-01

    Full Text Available We consider multiuser video transmission for users that are non-equidistantly positioned from base station. We propose a greedy algorithm for video streaming in a wireless system with capacity achieving channel coding, that implements the cross-layer principle by partially separating the physical and the application layer. In such a system the parameters at the physical layer are dependent on the packet length and the conditions in the wireless channel and the parameters at the application layer are dependent on the reduction of the expected distortion assuming no packet errors in the system. We also address the fairness in the multiuser video system with non-equidistantly positioned users. Our fairness algorithm is based on modified opportunistic round robin scheduling. We evaluate the performance of the proposed algorithms by simulating the transmission of H.264/AVC video signals in a TDMA wireless system.

  11. An Intervention Based on Video Feedback and Questioning to Improve Tactical Knowledge in Expert Female Volleyball Players.

    Science.gov (United States)

    Moreno, M Perla; Moreno, Alberto; García-González, Luis; Ureña, Aurelio; Hernández, César; Del Villar, Fernando

    2016-06-01

    This study applied an intervention program, based on video feedback and questioning, to expert female volleyball players to improve their tactical knowledge. The sample consisted of eight female attackers (26 ± 2.6 years old) from the Spanish National Volleyball Team, who were divided into an experimental group (n = 4) and a control group (n = 4). The video feedback and questioning program applied in the study was developed over eight reflective sessions and consisted of three phases: viewing of the selected actions, self-analysis and reflection by the attacker, and joint player-coach analysis. The attackers were videotaped in an actual game and four clips (situations) of each of the attackers were chosen for each reflective session. Two of the clips showed a correct action by the attacker, and two showed an incorrect decision. Tactical knowledge was measured by problem representation with a verbal protocol. The members of the experimental group showed adaptations in long-term memory, significantly improving their tactical knowledge. With respect to conceptual content, there was an increase in the total number of conditions verbalized by the players; with respect to conceptual sophistication, there was an increase in the indication of appropriate conditions with two or more details; and finally, with respect to conceptual structure, there was an increase in the use of double or triple conceptual structures. The intervention program, based on video feedback and questioning, in addition to on-court training sessions of expert volleyball players, appears to improve the athletes' tactical knowledge. © The Author(s) 2016.

  12. RTP-based broadcast streaming of high definition H.264/AVC video: an error robustness evaluation

    Institute of Scientific and Technical Information of China (English)

    HILLESTAD Odd Inge; JETLUND Ola; PERKIS Andrew

    2006-01-01

    In this work, we present an evaluation of the performance and error robustness of RTP-based broadcast streaming of high-quality high-definition (HD) H.264/AVC video. Using a fully controlled IP test bed (Hillestad et al., 2005), we broadcast high-definition video over RTP/UDP, and use an IP network emulator to introduce a varying amount of randomly distributed packet loss. A high-performance network interface monitoring card is used to capture the video packets into a trace file. Purpose-built software parses the trace file, analyzes the RTP stream and assembles the correctly received NAL units into an H.264/AVC Annex B byte stream file, which is subsequently decoded by JVT JM 10.1 reference software. The proposed measurement setup is a novel, practical and intuitive approach to perform error resilience testing of real-world H.264/AVC broadcast applications. Through a series of experiments, we evaluate some of the error resilience features of the H.264/AVC standard, and see how they perform at packet loss rates from 0.01% to 5%. The results confirmed that an appropriate slice partitioning scheme is essential to have a graceful degradation in received quality in the case of packet loss. While flexible macroblock ordering reduces the compression efficiency about 1 dB for our test material, reconstructed video quality is improved for loss rates above 0.25%.

  13. Color Reduction in an Authenticate Live 3D Point Cloud Video Streaming System

    Directory of Open Access Journals (Sweden)

    Zainab Sultani

    2016-07-01

    Full Text Available In this paper, an authenticate live 3D point cloud video streaming system is presented, using a low cost 3D sensor camera, the Microsoft Kinect. The proposed system is implemented on a client-server network infrastructure. The live 3D video is captured from the Kinect RGB-D sensor, then a 3D point cloud is generated and processed. Filtering and compression are used to handle the spatial and temporal redundancies. A color histogram based conditional filter is designed to reduce the color information for each frame based on the mean and standard deviation. In addition to the designed filter, a statistical outlier removal filter is used. A certificate-based authentication is used where the client will verify the identity of the server during the handshake process. The processed 3D point cloud video is live streamed over a TCP/IP protocol to the client. The system is evaluated in terms of: compression ratio, total bytes per points, peak signal to noise ratio (PSNR, and Structural Similarity (SSIM index. The experimental results demonstrate that the proposed video streaming system have a best case with SSIM 0.859, PSNR of 26.6 dB and with average compression ratio of 8.42 while the best average compression ratio case is about 15.43 with PSNR 18.5128 dB of and SSIM 0.7936.

  14. MAC-Layer Active Dropping for Real-Time Video Streaming in 4G Access Networks

    KAUST Repository

    She, James

    2010-12-01

    This paper introduces a MAC-layer active dropping scheme to achieve effective resource utilization, which can satisfy the application-layer delay for real-time video streaming in time division multiple access based 4G broadband wireless access networks. When a video frame is not likely to be reconstructed within the application-layer delay bound at a receiver for the minimum decoding requirement, the MAC-layer protocol data units of such video frame will be proactively dropped before the transmission. An analytical model is developed to evaluate how confident a video frame can be delivered within its application-layer delay bound by jointly considering the effects of time-varying wireless channel, minimum decoding requirement of each video frame, data retransmission, and playback buffer. Extensive simulations with video traces are conducted to prove the effectiveness of the proposed scheme. When compared to conventional cross-layer schemes using prioritized-transmission/retransmission, the proposed scheme is practically implementable for more effective resource utilization, avoiding delay propagation, and achieving better video qualities under certain conditions.

  15. Intelligent Stale-Frame Discards for Real-Time Video Streaming over Wireless Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Sheu Tsang-Ling

    2009-01-01

    Full Text Available Abstract This paper presents intelligent early packet discards (I-EPD for real-time video streaming over a multihop wireless ad hoc network. In a multihop wireless ad hoc network, the quality of transferring real-time video streams could be seriously degraded, since every intermediate node (IN functionally like relay device does not possess large buffer and sufficient bandwidth. Even worse, a selected relay node could leave or power off unexpectedly, which breaks the route to destination. Thus, a stale video frame is useless even if it can reach destination after network traffic becomes smooth or failed route is reconfigured. In the proposed I-EPD, an IN can intelligently determine whether a buffered video packet should be early discarded. For the purpose of validation, we implement the I-EPD on Linux-based embedded systems. Via the comparisons of performance metrics (packet/frame discards ratios, PSNR, etc., we demonstrate that video quality over a wireless ad hoc network can be substantially improved and unnecessary bandwidth wastage is greatly reduced.

  16. Video game characteristics, happiness and flow as predictors of addiction among video game players: A pilot study

    OpenAIRE

    Hull, Damien C.; Williams, Glenn A.; Griffiths, Mark D.

    2013-01-01

    Aims: Video games provide opportunities for positive psychological experiences such as flow-like phenomena during play and general happiness that could be associated with gaming achievements. However, research has shown that specific features of game play may be associated with problematic behaviour associated with addiction-like experiences. The study was aimed at analysing whether certain structural characteristics of video games, flow, and global happiness could be predictive of video game...

  17. Video game characteristics, happiness and flow as predictors of addiction among video game players: A pilot study.

    OpenAIRE

    Hull, DC; Williams, GA; Griffiths, MD

    2013-01-01

    AIMS: Video games provide opportunities for positive psychological experiences such as flow-like phenomena during play and general happiness that could be associated with gaming achievements. However, research has shown that specific features of game play may be associated with problematic behaviour associated with addiction-like experiences. The study was aimed at analysing whether certain structural characteristics of video games, flow, and global happiness could be predictive of video game...

  18. Video game characteristics, happiness and flow as predictors of addiction among video game players: A pilot study

    OpenAIRE

    Hull, DC; Williams, GA; Griffiths, MD

    2013-01-01

    Aims:\\ud Video games provide opportunities for positive psychological experiences such as flow-like phenomena during play and general happiness that could be associated with gaming achievements. However, research has shown that specific features of game play may be associated with problematic behaviour associated with addiction-like experiences. The study was aimed at analysing whether certain structural characteristics of video games, flow, and global happiness could be predictive of video g...

  19. Guest Editorial: Analysis and Retrieval of Events/Actions and Workflows in Video Streams

    DEFF Research Database (Denmark)

    Doulamis, Anastasios; Doulamis, Nikolaos; Bertini, Marco

    2016-01-01

    activities, actions, and procedures have been in the focus of the research community over the last years. This research area has strong impact on many real-life applications such as service quality assurance, compliance to the designed procedures in industrial plants, surveillance of people-dense areas (e.......g., thematic parks, critical public infrastructures), crisis management in public service areas (e.g., train stations, airports), security (detection of abnormal behaviors in surveillance videos), semantic characterization, and annotation of video streams in various domains (e.g., broadcast or user...

  20. Algorithms for Deterministic Call Admission Control of Pre-stored VBR Video Streams

    Directory of Open Access Journals (Sweden)

    Christos Tryfonas

    2009-08-01

    Full Text Available We examine the problem of accepting a new request for a pre-stored VBR video stream that has been smoothed using any of the smoothing algorithms found in the literature. The output of these algorithms is a piecewise constant-rate schedule for a Variable Bit-Rate (VBR stream. The schedule guarantees that the decoder buffer does not overflow or underflow. The problem addressed in this paper is the determination of the minimal time displacement of each new requested VBR stream so that it can be accommodated by the network and/or the video server without overbooking the committed traffic. We prove that this call-admission control problem for multiple requested VBR streams is NP-complete and inapproximable within a constant factor, by reducing it from the VERTEX COLOR problem. We also present a deterministic morphology-sensitive algorithm that calculates the minimal time displacement of a VBR stream request. The complexity of the proposed algorithm along with the experimental results we provide indicate that the proposed algorithm is suitable for real-time determination of the time displacement parameter during the call admission phase.

  1. Call Admission Control Algorithm for pre-stored VBR video streams

    CERN Document Server

    Tryfonas, Christos; Mehler, Andrew; Skiena, Steven

    2008-01-01

    We examine the problem of accepting a new request for a pre-stored VBR video stream that has been smoothed using any of the smoothing algorithms found in the literature. The output of these algorithms is a piecewise constant-rate schedule for a Variable Bit-Rate (VBR) stream. The schedule guarantees that the decoder buffer does not overflow or underflow. The problem addressed in this paper is the determination of the minimal time displacement of each new requested VBR stream so that it can be accomodated by the network and/or the video server without overbooking the committed traffic. We prove that this call-admission control problem for multiple requested VBR streams is NP-complete and inapproximable within a constant factor, by reducing it from the VERTEX COLOR problem. We also present a deterministic morphology-sensitive algorithm that calculates the minimal time displacement of a VBR stream request. The complexity of the proposed algorithm make it suitable for real-time determination of the time displacem...

  2. Meteoroid orbits from video meteors. The case of the Geminid stream

    Science.gov (United States)

    Hajduková, Mária, Jr.; Koten, Pavel; Kornoš, Leonard; Tóth, Juraj

    2017-09-01

    We use the Slovak and Czech video meteor observations, as well as video meteoroid orbits collected in the CAMS, SonotaCo, EDMOND and DMS catalogues, for an analysis of the distribution of meteoroid orbits within the stream of the Geminids and of the dispersion of their radiants. We concentrate on the influence of the measurement errors on the precision of the orbits obtained from the video networks that are based on various meteor-detection software packages and various meteor orbital element softwares. The Geminids radiant dispersion obtained from the large video catalogues reaches the dispersion of the radio observed Geminids, whereby the diffused marginal regions are affected mostly by meteoroids with extreme values (small or large) of the semi-major axes. Meteoroids of shorter semi-major axes concentrate at the eastern side of the radiant area and those of longer semi-major axes at the western part. The observed orbital dispersions in the Geminid stream described by the median absolute deviation range from 0.029 to 0.042 AU-1 for the video catalogues. The distribution of the semi-major axes of video meteors in all the databases, except for the Ondřejov (Czech) data, seem to be systematically biased in comparison with the photographic and radio meteors. The determined velocities of the video data are underestimated, probably as a consequence of the methods used for the positional and velocity measurements. The largest shift is observed in the EDMOND and SonotaCo catalogues. Except for the measurement errors which influence the analyses and their interpretations, we also point out the problem of the uncertainties of the numerical integration procedures that influence the simulations' results. Several experimental integrations of the Geminids parent asteroid, which we performed from the present to the past and then back to the year 2015, showed that a complete reproduction, including also the mean anomaly, is only possible for a time span of about 2700 years.

  3. Performance analysis of medical video streaming over mobile WiMAX.

    Science.gov (United States)

    Alinejad, Ali; Philip, N; Istepanian, R H

    2010-01-01

    Wireless medical ultrasound streaming is considered one of the emerging application within the broadband mobile healthcare domain. These applications are considered as bandwidth demanding services that required high data rates with acceptable diagnostic quality of the transmitted medical images. In this paper, we present the performance analysis of a medical ultrasound video streaming acquired via special robotic ultrasonography system over emulated WiMAX wireless network. The experimental set-up of this application is described together with the performance of the relevant medical quality of service (m-QoS) metrics.

  4. Task-oriented quality assessment and adaptation in real-time mission critical video streaming applications

    Science.gov (United States)

    Nightingale, James; Wang, Qi; Grecos, Christos

    2015-02-01

    In recent years video traffic has become the dominant application on the Internet with global year-on-year increases in video-oriented consumer services. Driven by improved bandwidth in both mobile and fixed networks, steadily reducing hardware costs and the development of new technologies, many existing and new classes of commercial and industrial video applications are now being upgraded or emerging. Some of the use cases for these applications include areas such as public and private security monitoring for loss prevention or intruder detection, industrial process monitoring and critical infrastructure monitoring. The use of video is becoming commonplace in defence, security, commercial, industrial, educational and health contexts. Towards optimal performances, the design or optimisation in each of these applications should be context aware and task oriented with the characteristics of the video stream (frame rate, spatial resolution, bandwidth etc.) chosen to match the use case requirements. For example, in the security domain, a task-oriented consideration may be that higher resolution video would be required to identify an intruder than to simply detect his presence. Whilst in the same case, contextual factors such as the requirement to transmit over a resource-limited wireless link, may impose constraints on the selection of optimum task-oriented parameters. This paper presents a novel, conceptually simple and easily implemented method of assessing video quality relative to its suitability for a particular task and dynamically adapting videos streams during transmission to ensure that the task can be successfully completed. Firstly we defined two principle classes of tasks: recognition tasks and event detection tasks. These task classes are further subdivided into a set of task-related profiles, each of which is associated with a set of taskoriented attributes (minimum spatial resolution, minimum frame rate etc.). For example, in the detection class

  5. Optimisation Issues of High Throughput Medical Data and Video Streaming Traffic in 3G Wireless Environments.

    Science.gov (United States)

    Istepanian, R S H; Philip, N

    2005-01-01

    In this paper we describe some of the optimisation issues relevant to the requirements of high throughput of medical data and video streaming traffic in 3G wireless environments. In particular we present a challenging 3G mobile health care application that requires a demanding 3G medical data throughput. We also describe the 3G QoS requirement of mObile Tele-Echography ultra-Light rObot system (OTELO that is designed to provide seamless 3G connectivity for real-time ultrasound medical video streams and diagnosis from a remote site (robotic and patient station) manipulated by an expert side (specialists) that is controlling the robotic scanning operation and presenting a real-time feedback diagnosis using 3G wireless communication links.

  6. The effects of camera jitter for background subtraction algorithms on fused infrared-visible video streams

    Science.gov (United States)

    Becker, Stefan; Scherer-Negenborn, Norbert; Thakkar, Pooja; Hübner, Wolfgang; Arens, Michael

    2016-10-01

    This paper is a continuation of the work of Becker et al.1 In their work, they analyzed the robustness of various background subtraction algorithms on fused video streams originating from visible and infrared cameras. In order to cover a broader range of background subtraction applications, we show the effects of fusing infrared-visible video streams from vibrating cameras on a large set of background subtraction algorithms. The effectiveness is quantitatively analyzed on recorded data of a typical outdoor sequence with a fine-grained and accurate annotation of the images. Thereby, we identify approaches which can benefit from fused sensor signals with camera jitter. Finally conclusions on what fusion strategies should be preferred under such conditions are given.

  7. Testing environment for video streaming support using open source tools

    Directory of Open Access Journals (Sweden)

    Franco Arturo Urbano O.

    2016-01-01

    Full Text Available Dentro de las tecnologías que hoy en día tienen implicaciones importantes en ámbitos como la educación, la salud y el sector productivo, se destaca el videostreaming. Esto teniendo en cuenta las ventajas que esta tecnología ofrece para el acceso a contenidos multimedia de manera remota, en vivo o fuera de línea. El objetivo de éste artículo es proponer un entorno de pruebas para el soporte del servicio de videostreaming haciendo uso de herramientas libres. Así mismo, este trabajo propone como parte de éste entorno, una herramienta para la medición de estrés llamada Hermes, la cual permite obtener los tiempos de respuesta producto de las múltiples conexiones RTSP a servidores de streaming. La metodología usada para el desarrollo de este trabajo está dividida en 4 fases: análisis de tecnologías y herramientas, configuración del entorno de videostreaming, diseño e implementación de Hermes y pruebas. Está metodología permitió la construcción del entorno de pruebas y su evaluación, a través de la herramienta de medición de estrés Hermes. Finalmente, mediante este trabajo se demuestra como el entorno de pruebas presentado, se convierte en un punto de referencia para diversos entornos de aplicación que requieran el montaje e implementación del servicio de videostreaming.

  8. Enhancing Scalability in On-Demand Video Streaming Services for P2P Systems

    Directory of Open Access Journals (Sweden)

    R. Arockia Xavier Annie

    2012-01-01

    Full Text Available Recently, many video applications like video telephony, video conferencing, Video-on-Demand (VoD, and so forth have produced heterogeneous consumers in the Internet. In such a scenario, media servers play vital role when a large number of concurrent requests are sent by heterogeneous users. Moreover, the server and distributed client systems participating in the Internet communication have to provide suitable resources to heterogeneous users to meet their requirements satisfactorily. The challenges in providing suitable resources are to analyze the user service pattern, bandwidth and buffer availability, nature of applications used, and Quality of Service (QoS requirements for the heterogeneous users. Therefore, it is necessary to provide suitable techniques to handle these challenges. In this paper, we propose a framework for peer-to-peer- (P2P- based VoD service in order to provide effective video streaming. It consists of four functional modules, namely, Quality Preserving Multivariate Video Model (QPMVM for efficient server management, tracker for efficient peer management, heuristic-based content distribution, and light weight incentivized sharing mechanism. The first two of these modules are confined to a single entity of the framework while the other two are distributed across entities. Experimental results show that the proposed framework avoids overloading the server, increases the number of clients served, and does not compromise on QoS, irrespective of the fact that the expected framework is slightly reduced.

  9. An Approach to Streaming Video Segmentation With Sub-Optimal Low-Rank Decomposition.

    Science.gov (United States)

    Li, Chenglong; Lin, Liang; Zuo, Wangmeng; Wang, Wenzhong; Tang, Jin

    2016-05-01

    This paper investigates how to perform robust and efficient video segmentation while suppressing the effects of data noises and/or corruptions, and an effective approach is introduced to this end. First, a general algorithm, called sub-optimal low-rank decomposition (SOLD), is proposed to pursue the low-rank representation for video segmentation. Given the data matrix formed by supervoxel features of an observed video sequence, SOLD seeks a sub-optimal solution by making the matrix rank explicitly determined. In particular, the representation coefficient matrix with the fixed rank can be decomposed into two sub-matrices of low rank, and then we iteratively optimize them with closed-form solutions. Moreover, we incorporate a discriminative replication prior into SOLD based on the observation that small-size video patterns tend to recur frequently within the same object. Second, based on SOLD, we present an efficient inference algorithm to perform streaming video segmentation in both unsupervised and interactive scenarios. More specifically, the constrained normalized-cut algorithm is adopted by incorporating the low-rank representation with other low level cues and temporal consistent constraints for spatio-temporal segmentation. Extensive experiments on two public challenging data sets VSB100 and SegTrack suggest that our approach outperforms other video segmentation approaches in both accuracy and efficiency.

  10. Energy-Efficient Bandwidth Allocation for Multiuser Scalable Video Streaming over WLAN

    Directory of Open Access Journals (Sweden)

    Lafruit Gauthier

    2008-01-01

    Full Text Available Abstract We consider the problem of packet scheduling for the transmission of multiple video streams over a wireless local area network (WLAN. A cross-layer optimization framework is proposed to minimize the wireless transceiver energy consumption while meeting the user required visual quality constraints. The framework relies on the IEEE 802.11 standard and on the embedded bitstream structure of the scalable video coding scheme. It integrates an application-level video quality metric as QoS constraint (instead of a communication layer quality metric with energy consumption optimization through link layer scaling and sleeping. Both energy minimization and min-max energy optimization strategies are discussed. Simulation results demonstrate significant energy gains compared to the state-of-the-art approaches.

  11. Comprehensive Protection of Data-Partitioned Video for Broadband Wireless IPTV Streaming

    Directory of Open Access Journals (Sweden)

    Laith Al-Jobouri

    2012-01-01

    Full Text Available This paper examines the threat to video streaming from slow and fast fading, traffic congestion, and channel packet drops. The proposed response is a combination of: rateless channel coding, which is adaptively applied; data-partitioned source coding to exploit prioritized packetization; and duplicate slice provision, which is the focus of the evaluation in this paper. The paper also considers the distribution of intra-refresh macroblocks as a means of avoiding sudden data rate increases. When error bursts occur, this paper shows that duplicate slices are certainly necessary but this provision is more effective for medium quality video than it is for high quality video. The percentage of intra-refresh macroblocks can be low and still reduce the impact of temporal error propagation.

  12. H.264/MPEG-4 AVC Video Streaming Evaluation of LR-EE-AOMDV Protocol in MANET

    Directory of Open Access Journals (Sweden)

    Karthikeyan Eswaramoorthy

    2017-01-01

    Full Text Available Deployment of conversational real-time applications like VoIP (Voice over IP and videoconferencing require new challenges in Long-Term Evolution (LTE networks such as Internet. Quality of video delivered over the Internet has been determined in terms of Quality-of-Service (QoS and Quality-of-Experience (QoE. QoS includes packet delivery ratio, average end-to-end delay, throughput, routing overhead, etc. QoE is a qualitative measure of videos transmitted over Internet. In this paper, we evaluate the performance of Link Reliable Energy Efficient Ad hoc On-demand Multipath Distance Vector (LR-EE-AOMDV routing on H.264/MPEG-4 AVC video streaming under both Distributed Coordination Function (DCF and Enhanced Distributed Coordination Function (EDCF using NS2.34 and Enhanced EvalVid framework. Simulation results show that the LR-EE-AOMDV performs better than AOMDV and OMMRE-AOMDV.

  13. Reliable Adaptive Video Streaming Driven by Perceptual Semantics for Situational Awareness.

    Science.gov (United States)

    Pimentel-Niño, M A; Saxena, Paresh; Vazquez-Castro, M A

    2015-01-01

    A novel cross-layer optimized video adaptation driven by perceptual semantics is presented. The design target is streamed live video to enhance situational awareness in challenging communications conditions. Conventional solutions for recreational applications are inadequate and novel quality of experience (QoE) framework is proposed which allows fully controlled adaptation and enables perceptual semantic feedback. The framework relies on temporal/spatial abstraction for video applications serving beyond recreational purposes. An underlying cross-layer optimization technique takes into account feedback on network congestion (time) and erasures (space) to best distribute available (scarce) bandwidth. Systematic random linear network coding (SRNC) adds reliability while preserving perceptual semantics. Objective metrics of the perceptual features in QoE show homogeneous high performance when using the proposed scheme. Finally, the proposed scheme is in line with content-aware trends, by complying with information-centric-networking philosophy and architecture.

  14. Lightweight Object Tracking in Compressed Video Streams Demonstrated in Region-of-Interest Coding

    Directory of Open Access Journals (Sweden)

    Rik Van de Walle

    2007-01-01

    Full Text Available Video scalability is a recent video coding technology that allows content providers to offer multiple quality versions from a single encoded video file in order to target different kinds of end-user devices and networks. One form of scalability utilizes the region-of-interest concept, that is, the possibility to mark objects or zones within the video as more important than the surrounding area. The scalable video coder ensures that these regions-of-interest are received by an end-user device before the surrounding area and preferably in higher quality. In this paper, novel algorithms are presented making it possible to automatically track the marked objects in the regions of interest. Our methods detect the overall motion of a designated object by retrieving the motion vectors calculated during the motion estimation step of the video encoder. Using this knowledge, the region-of-interest is translated, thus following the objects within. Furthermore, the proposed algorithms allow adequate resizing of the region-of-interest. By using the available information from the video encoder, object tracking can be done in the compressed domain and is suitable for real-time and streaming applications. A time-complexity analysis is given for the algorithms proving the low complexity thereof and the usability for real-time applications. The proposed object tracking methods are generic and can be applied to any codec that calculates the motion vector field. In this paper, the algorithms are implemented within MPEG-4 fine-granularity scalability codec. Different tests on different video sequences are performed to evaluate the accuracy of the methods. Our novel algorithms achieve a precision up to 96.4%.

  15. Lightweight Object Tracking in Compressed Video Streams Demonstrated in Region-of-Interest Coding

    Directory of Open Access Journals (Sweden)

    Lerouge Sam

    2007-01-01

    Full Text Available Video scalability is a recent video coding technology that allows content providers to offer multiple quality versions from a single encoded video file in order to target different kinds of end-user devices and networks. One form of scalability utilizes the region-of-interest concept, that is, the possibility to mark objects or zones within the video as more important than the surrounding area. The scalable video coder ensures that these regions-of-interest are received by an end-user device before the surrounding area and preferably in higher quality. In this paper, novel algorithms are presented making it possible to automatically track the marked objects in the regions of interest. Our methods detect the overall motion of a designated object by retrieving the motion vectors calculated during the motion estimation step of the video encoder. Using this knowledge, the region-of-interest is translated, thus following the objects within. Furthermore, the proposed algorithms allow adequate resizing of the region-of-interest. By using the available information from the video encoder, object tracking can be done in the compressed domain and is suitable for real-time and streaming applications. A time-complexity analysis is given for the algorithms proving the low complexity thereof and the usability for real-time applications. The proposed object tracking methods are generic and can be applied to any codec that calculates the motion vector field. In this paper, the algorithms are implemented within MPEG-4 fine-granularity scalability codec. Different tests on different video sequences are performed to evaluate the accuracy of the methods. Our novel algorithms achieve a precision up to 96.4 .

  16. Mobility-Aware Video Streaming in MIMO-Capable Heterogeneous Wireless Networks

    Directory of Open Access Journals (Sweden)

    Hayoung Oh

    2016-01-01

    Full Text Available Multiple input and multiple output (MIMO is a well-known technique for the exploitation of the spatial multiplexing (MUX and spatial diversity (DIV gains that improve transmission quality and reliability. In this paper, we propose a quality-adaptive scheme for handover and forwarding that supports mobile-video-streaming services in MIMO-capable, heterogeneous wireless-access networks such as those for Wi-Fi and LTE. Unlike previous handover schemes, we propose an appropriate metric for the selection of the wireless technology and the MIMO mode, whereby a new address availability and the wireless-channel quality, both of which are in a new wireless-access network so that the handover and video-playing delays are reduced, are considered. While an MN maintains its original care-of address (oCoA, the video packets destined for the MN are forwarded with the MIMO technique (MUX mode or DIV mode on top of a specific wireless technology from the previous Access Router (pAR to the new Access Router (nAR until they finally reach the MN; however, to guarantee a high video-streaming quality and to limit the video-packet-forwarding hops between the pAR and the nAR, the MN creates a new CoA (nCOA within the delay threshold of the QoS/quality of experience (QoE satisfaction result, and then, as much as possible, the video packet is forwarded with the MUX. Through extensive simulations, we show that the proposed scheme is a significant improvement upon the other schemes.

  17. Low-Complexity Error-Control Methods for Scalable Video Streaming

    Institute of Scientific and Technical Information of China (English)

    Zhijie Zhao; Jom Ostermann

    2012-01-01

    In this paper, low-complexity error-resilience and error-concealment methods for the scalable video coding (SVC) extension of H.264/AVC are described. At the encoder, multiple-description coding (MDC) is used as error-resilient coding. Balanced scalable multiple descriptions are generated by mixing the pre-encoded scalable bit streams. Each description is wholly decodable using a standard SVC decoder. A preprocessor can be placed before an SVC decoder to extract the packets from the highest-quality bit stream. At the decoder, error concealment involves using a lightweight decoder preprocessor to generate a valid bit stream from the available network abstraction layer (NAL) units when medium-grain scalability (MGS) layers are used. Modifications are made to the NAL unit header or slice header if some NAL units of MGS layers are lost. The number of additional packets that a decoder discards as a result of a packet loss is minimized. The proposed error-resilience and error-concealment methods require little computation, which makes them suitable for real-time video streaming. Experiment results show that the proposed methods significantly reduce quality degradation caused by packet loss.

  18. Wireless live streaming video of surgical operations: an evaluation of communication quality.

    Science.gov (United States)

    Schneider, Armin; Wilhelm, Dirk; Doll, Dietrich; Rauschenbach, Uwe; Finkenzeller, Michael; Wirnhier, Helga; Illgner, Klaus; Feussner, Hubertus

    2007-01-01

    We evaluated a mobile video system for surgical teleconsultation. A video streaming server in the operating room transmitted video and audio to a hand-held computer (personal digital assistant [PDA]) over a wireless local area network. Two groups of 20 surgeons (each with 12 qualified surgeons and eight surgeons between the 2nd and the 4th year of training) participated in the tests. For voice transmission, correct understanding of numbers was achieved in 100% of the cases (n = 1000) and 98% of medical terms (n = 400). The quality of the video displayed on the PDA was assessed by the recognition of different operating room scenarios. Only 62% (SD 17) of the structures were identified clearly on the hand-held device (n = 400). The accuracy improved to 78% (SD 15) (n = 400) if the same scenario was observed on a larger (50 cm) video screen (p < 0.001). Accuracy was significantly better if audio conversation was possible. The quality evaluation by the consultants showed that the PDA display size and quality were sufficient for clinical use.

  19. Evaluation of an interactive web-based nursing course with streaming videos for medication administration skills.

    Science.gov (United States)

    Sowan, Azizeh K; Idhail, Jamila Abu

    2014-08-01

    Nursing students should exhibit competence in nursing skills in order to provide safe and quality patient care. This study describes the design and students' response to an interactive web-based course using streaming video technology tailored to students' needs and the course objectives of the fundamentals of nursing skills clinical course. A mixed-methodology design was used to describe the experience of 102 first-year undergraduate nursing students at a school of nursing in Jordan who were enrolled in the course. A virtual course with streaming videos was designed to demonstrate medication administration fundamental skills. The videos recorded the ideal lab demonstration of the skills, and real-world practice performed by registered nurses for patients in a hospital setting. After course completion, students completed a 30-item satisfaction questionnaire, 8 self-efficacy scales, and a 4-item scale solicited their preferences of using the virtual course as a substitute or a replacement of the lab demonstration. Students' grades in the skill examination of the procedures were measured. Relationships between the main variables and predictors of satisfaction and self-efficacy were examined. Students were satisfied with the virtual course (3.9 ± 0.56, out of a 5-point scale) with a high-perceived overall self-efficacy (4.38 ± 0.42, out of a 5-point scale). Data showed a significant correlation between student satisfaction, self-efficacy and achievement in the virtual course (r = 0.45-0.49, p streaming videos for clinical courses is a complex process that should be carefully designed to positively influence the learning experience. However, the learning benefits gained from such pedagogical approach are worth faculty, institution and students' efforts. Published by Elsevier Ireland Ltd.

  20. Network Degradation Effects on Different Codec Types and Characteristics of Video Streaming

    Directory of Open Access Journals (Sweden)

    Jaroslav Frnda

    2014-01-01

    Full Text Available Nowadays, there is a quickly growing demand for the transmission of voice, video and data over an IP based network. Multimedia, whether we are talking about broadcast, audio and video transmission and others, from a global perspective is growing exponentially with time. With incoming requests from users, new technologies for data transfer are continually developing. Data must be delivered reliably and with the fewest losses at such high speed. Video quality as part of multimedia technology has a very important role nowadays. It is influenced by several factors, where each of them can have many forms and processing. Network performance is the major degradation effect that influences the quality of resulting image. Poor network performance (lack of link capacity, high network load… causes data packet losses or different delivery time for each packet. This work focuses exactly on these network phenomena. It examines the impact of different delays and packet losses on the quality parameters of triple play services, to evaluate the results using objective methods. The aim of this work is to bring a detailed view on the performance of video streaming over IP-based networks.

  1. Performance Evaluation of OSPF and EIGRP Routing Protocols for Video Streaming over Next Generation Networks

    Directory of Open Access Journals (Sweden)

    Francis L Lugayizi

    2015-09-01

    Full Text Available The challenge in performance of Next Generation Networks (NGNs is a growing concern. Bandwidth limitation for multimedia applications in NGNs such as voice and video telephony along with the increasing number of applications on the Internet, service classification and efficient resource management have all become quite challenging tasks. In order to improve the service quality in video streaming especially, there has to be efficient resource and traffic management, and using routing protocols is one way in which this can be done. We designed three network models that are configured with OSPF, EIGRP and one with both OPSF and EIGRP routing protocols, and then used the QoS parameters of throughput, packet loss, convergence time, mean latency and end-to-end delay as our metrics to evaluate the performance of OSPF and EIGRP. Our main source of network traffic was a typical video conferencing application. The results obtained during our experiments indicate that combining both EIGRP and OSPF is more reliable in providing Quality of Service than OSPF routing protocol when the main traffic used in the network is video, but when dealing with a standalone real time application network, EIGRP is better than OSPF.

  2. Content-adaptive robust error concealment for packet-lossy H.264 video streaming

    Institute of Scientific and Technical Information of China (English)

    LIAO Ning; YAN Dan; QUAN Zi-yi; MEN Ai-dong

    2006-01-01

    In this paper, we present a spatio-temporal post-processing error concealment (EC) algorithm designed initially for a H.264 video-streaming scheme over packet-lossy networks. It aims at optimizing the subjective quality of the restored video under the constraints of low delay and computational complexity, which are critical to real-time applications and portable devices having limited resources. Specifically, it takes into consideration the physical property of motion field in order to achieve more meaningful perceptual video quality, in addition to the improved objective PSNR. Further, a simple bilinear spatial interpolation approach is combined with the improved boundary-match (B-M) based temporal EC approach according to texture and motion activity analysis. Finally, we propose a low complexity temporal EC method based on motion vector interpolation as a replacement of the B-M based approach in the scheme under low-computation requirement, or as a complement to further improve the scheme's performance in applications having enough computation resources. Extensive experiments demonstrated that the proposal features not only better reconstruction, objectively and subjectively, than JM benchmark, but also robustness to different video sequences.

  3. A scalable delivery system based on RTP JPEG2000 video stream format

    Science.gov (United States)

    Itakura, Eisaburo; Edwards, Eric; Futenma, Satoshi; Tomita, Nobuyoshi; Yamane, Kenji

    2003-11-01

    Demands for scalable delivery systems are increasing for Internet applications. Users want to receive content from a single source regardless of the consumer devices they are using PC, TV, PDA and mobile phone. To realize this type of application, we have developed a scalable delivery system based on a RTP JPEG2000 video stream format that we have proposed to IETF. This system can provide video delivery and Quality of Service from a single layered content for users who require different image quality/resolution/color depending on the device they are using. This system could be a next generation communication platform, allowing us to realize a ubiquitous value network by combining network and codec technologies.

  4. Reliable Adaptive Video Streaming Driven by Perceptual Semantics for Situational Awareness

    Directory of Open Access Journals (Sweden)

    M. A. Pimentel-Niño

    2015-01-01

    presented. The design target is streamed live video to enhance situational awareness in challenging communications conditions. Conventional solutions for recreational applications are inadequate and novel quality of experience (QoE framework is proposed which allows fully controlled adaptation and enables perceptual semantic feedback. The framework relies on temporal/spatial abstraction for video applications serving beyond recreational purposes. An underlying cross-layer optimization technique takes into account feedback on network congestion (time and erasures (space to best distribute available (scarce bandwidth. Systematic random linear network coding (SRNC adds reliability while preserving perceptual semantics. Objective metrics of the perceptual features in QoE show homogeneous high performance when using the proposed scheme. Finally, the proposed scheme is in line with content-aware trends, by complying with information-centric-networking philosophy and architecture.

  5. Encryption for confidentiality of the network and influence of this to the quality of streaming video through network

    Science.gov (United States)

    Sevcik, L.; Uhrin, D.; Frnda, J.; Voznak, M.; Toral-Cruz, Homer; Mikulec, M.; Jakovlev, Sergej

    2015-05-01

    Nowadays, the interest in real-time services, like audio and video, is growing. These services are mostly transmitted over packet networks, which are based on IP protocol. It leads to analyses of these services and their behavior in such networks which are becoming more frequent. Video has become the significant part of all data traffic sent via IP networks. In general, a video service is one-way service (except e.g. video calls) and network delay is not such an important factor as in a voice service. Dominant network factors that influence the final video quality are especially packet loss, delay variation and the capacity of the transmission links. Analysis of video quality concentrates on the resistance of video codecs to packet loss in the network, which causes artefacts in the video. IPsec provides confidentiality in terms of safety, integrity and non-repudiation (using HMAC-SHA1 and 3DES encryption for confidentiality and AES in CBC mode) with an authentication header and ESP (Encapsulating Security Payload). The paper brings a detailed view of the performance of video streaming over an IP-based network. We compared quality of video with packet loss and encryption as well. The measured results demonstrated the relation between the video codec type and bitrate to the final video quality.

  6. Intelligent Packet Shaper to Avoid Network Congestion for Improved Streaming Video Quality at Clients

    DEFF Research Database (Denmark)

    Kaul, Manohar; Khosla, Rajiv; Mitsukura, Y

    2003-01-01

    to predict, to a very high level of accuracy, a state of congestion based upon the training data collected about the network behaviour. Initially, the current traffic shaping technologies are discussed and later a simulation in a controlled environment is illustrated to exhibit the effects...... of this intelligent traffic-shaping algorithm on the underlying network real time packet traffic and the eradication of unwanted abruption in the streaming video qualiy. This paper concluded from the end results of the simulation that neural networks are a very superior means of modeling real-time traffic...

  7. DEFINITION AND ANALYSIS OF MOTION ACTIVITY AFTER-STROKE PATIENT FROM THE VIDEO STREAM

    Directory of Open Access Journals (Sweden)

    M. Yu. Katayev

    2014-01-01

    Full Text Available This article describes an approach to the assessment of motion activity of man in after-stroke period, allowing the doctor to get new information to give a more informed recommendations on rehabilitation treatment than in traditional approaches. Consider description of the hardware-software complex for determination and analysis of motion activity after-stroke patient for the video stream. The article provides a description of the complex, its algorithmic filling and the results of the work on the example of processing of the actual data. The algorithms and technology to significantly accelerate the gait analysis and improve the quality of diagnostics post-stroke patients.

  8. Processing features of audio and video files

    Directory of Open Access Journals (Sweden)

    E. N. Vydalko

    2012-11-01

    Full Text Available Currently the analog videotape recorders using is a thing of the past. Therefore, digital video recording became actual and attractive for the users who put image quality above all else. It is important to make a video recording in digital format without digital signal into analog signal converting. The last leads to a significant loss of quality records. A program processes video stream of digital cable TV is described in this article. Also it can convert video stream of digital cable TV into a format that can easily be used by any computer or DVD-player in digital form.

  9. Compressed domain moving object extraction algorithm for MPEG-2 video stream

    Science.gov (United States)

    Yang, Gaobo; Wang, Xiaojing; Zhang, Zhaoyang

    2007-11-01

    In this paper, a compressed domain moving object extraction algorithm is proposed for MPEG-2 video stream. It is mainly based on the histogram analysis of motion vectors, which can be easily obtained by partially decoding the MPEG-2 video stream. The whole algorithm framework can be divided into three key steps: motion vector pre-processing, histogram analysis of motion vector and motion vector similarity based region growing for final mask generation. A piecewise cubic hermit interpolation is utilized to form a dense motion field. The outputs of region growing algorithm based on similarity matching are the final segmentation results of moving object. These final segmentation results are further smoothed and interpolated by B-spline curve estimation. Experimental results on several test sequences demonstrate that desirable segmentation results are obtained. The accuracy of segmentation results is improved obviously, nearly to pixel level accuracy because of B-spline curve representation of segmented object. For segmentation efficiency, the processing speed is about 30ms per frame, which can meet the requirements of real time applications.

  10. Cross-Layer Techniques for Adaptive Video Streaming over Wireless Networks

    Directory of Open Access Journals (Sweden)

    Yufeng Shan

    2005-02-01

    Full Text Available Real-time streaming media over wireless networks is a challenging proposition due to the characteristics of video data and wireless channels. In this paper, we propose a set of cross-layer techniques for adaptive real-time video streaming over wireless networks. The adaptation is done with respect to both channel and data. The proposed novel packetization scheme constructs the application layer packet in such a way that it is decomposed exactly into an integer number of equal-sized radio link protocol (RLP packets. FEC codes are applied within an application packet at the RLP packet level rather than across different application packets and thus reduce delay at the receiver. A priority-based ARQ, together with a scheduling algorithm, is applied at the application layer to retransmit only the corrupted RLP packets within an application layer packet. Our approach combines the flexibility and programmability of application layer adaptations, with low delay and bandwidth efficiency of link layer techniques. Socket-level simulations are presented to verify the effectiveness of our approach.

  11. Joint Optimized CPU and Networking Control Scheme for Improved Energy Efficiency in Video Streaming on Mobile Devices

    Directory of Open Access Journals (Sweden)

    Sung-Woong Jo

    2017-01-01

    Full Text Available Video streaming service is one of the most popular applications for mobile users. However, mobile video streaming services consume a lot of energy, resulting in a reduced battery life. This is a critical problem that results in a degraded user’s quality of experience (QoE. Therefore, in this paper, a joint optimization scheme that controls both the central processing unit (CPU and wireless networking of the video streaming process for improved energy efficiency on mobile devices is proposed. For this purpose, the energy consumption of the network interface and CPU is analyzed, and based on the energy consumption profile a joint optimization problem is formulated to maximize the energy efficiency of the mobile device. The proposed algorithm adaptively adjusts the number of chunks to be downloaded and decoded in each packet. Simulation results show that the proposed algorithm can effectively improve the energy efficiency when compared with the existing algorithms.

  12. A Video Game Platform for Exploring Satellite and In-Situ Data Streams

    Science.gov (United States)

    Cai, Y.

    2014-12-01

    Exploring spatiotemporal patterns of moving objects are essential to Earth Observation missions, such as tracking, modeling and predicting movement of clouds, dust, plumes and harmful algal blooms. Those missions involve high-volume, multi-source, and multi-modal imagery data analysis. Analytical models intend to reveal inner structure, dynamics, and relationship of things. However, they are not necessarily intuitive to humans. Conventional scientific visualization methods are intuitive but limited by manual operations, such as area marking, measurement and alignment of multi-source data, which are expensive and time-consuming. A new development of video analytics platform has been in progress, which integrates the video game engine with satellite and in-situ data streams. The system converts Earth Observation data into articulated objects that are mapped from a high-dimensional space to a 3D space. The object tracking and augmented reality algorithms highlight the objects' features in colors, shapes and trajectories, creating visual cues for observing dynamic patterns. The head and gesture tracker enable users to navigate the data space interactively. To validate our design, we have used NASA SeaWiFS satellite images of oceanographic remote sensing data and NOAA's in-situ cell count data. Our study demonstrates that the video game system can reduce the size and cost of traditional CAVE systems in two to three orders of magnitude. This system can also be used for satellite mission planning and public outreaching.

  13. Empirical evaluation of H.265/HEVC-based dynamic adaptive video streaming over HTTP (HEVC-DASH)

    Science.gov (United States)

    Irondi, Iheanyi; Wang, Qi; Grecos, Christos

    2014-05-01

    Real-time HTTP streaming has gained global popularity for delivering video content over Internet. In particular, the recent MPEG-DASH (Dynamic Adaptive Streaming over HTTP) standard enables on-demand, live, and adaptive Internet streaming in response to network bandwidth fluctuations. Meanwhile, emerging is the new-generation video coding standard, H.265/HEVC (High Efficiency Video Coding) promises to reduce the bandwidth requirement by 50% at the same video quality when compared with the current H.264/AVC standard. However, little existing work has addressed the integration of the DASH and HEVC standards, let alone empirical performance evaluation of such systems. This paper presents an experimental HEVC-DASH system, which is a pull-based adaptive streaming solution that delivers HEVC-coded video content through conventional HTTP servers where the client switches to its desired quality, resolution or bitrate based on the available network bandwidth. Previous studies in DASH have focused on H.264/AVC, whereas we present an empirical evaluation of the HEVC-DASH system by implementing a real-world test bed, which consists of an Apache HTTP Server with GPAC, an MP4Client (GPAC) with open HEVC-based DASH client and a NETEM box in the middle emulating different network conditions. We investigate and analyze the performance of HEVC-DASH by exploring the impact of various network conditions such as packet loss, bandwidth and delay on video quality. Furthermore, we compare the Intra and Random Access profiles of HEVC coding with the Intra profile of H.264/AVC when the correspondingly encoded video is streamed with DASH. Finally, we explore the correlation among the quality metrics and network conditions, and empirically establish under which conditions the different codecs can provide satisfactory performance.

  14. Multiple description coding with spatial-temporal hybrid interpolation for video streaming in peer-to-peer networks

    Institute of Scientific and Technical Information of China (English)

    LU Meng-ting; LIN Chang-kuan; YAO Jason; CHEN Homer H.

    2006-01-01

    In this paper, we present an innovative design of multiple description coding with spatial-temporal hybrid interpolation (MDC-STHI) for peer-to-peer (P2P) video streaming. MDC can be effective in P2P networks because the nature of overlay routing makes path diversity more feasible. However, most MDC schemes require a redesign of video coding systems and are not cost-effective for wide deployment. We base our work on multiple state video coding, a form of MDC that can utilize standard codecs. Two quarter-sized video bit streams are generated as redundancies and embedded in the original-sized streams. With MDC-STHI, the nodes in P2P network can adjust the streaming traffic to satisfy the constraints of their devices and network environment. By design, the redundancies are used to compensate for missing frames, and can also be streamed independently to fulfill certain needs of low rate, low resolution applications. For better error concealment, optimal weights for spatial and temporal interpolation are determined at the source, quantized, and included in redundancies.

  15. Two Dimensional Array Based Overlay Network for Balancing Load of Peer-to-Peer Live Video Streaming

    Science.gov (United States)

    Faruq Ibn Ibrahimy, Abdullah; Rafiqul, Islam Md; Anwar, Farhat; Ibn Ibrahimy, Muhammad

    2013-12-01

    The live video data is streaming usually in a tree-based overlay network or in a mesh-based overlay network. In case of departure of a peer with additional upload bandwidth, the overlay network becomes very vulnerable to churn. In this paper, a two dimensional array-based overlay network is proposed for streaming the live video stream data. As there is always a peer or a live video streaming server to upload the live video stream data, so the overlay network is very stable and very robust to churn. Peers are placed according to their upload and download bandwidth, which enhances the balance of load and performance. The overlay network utilizes the additional upload bandwidth of peers to minimize chunk delivery delay and to maximize balance of load. The procedure, which is used for distributing the additional upload bandwidth of the peers, distributes the additional upload bandwidth to the heterogeneous strength peers in a fair treat distribution approach and to the homogeneous strength peers in a uniform distribution approach. The proposed overlay network has been simulated by Qualnet from Scalable Network Technologies and results are presented in this paper.

  16. Combined Wavelet Video Coding and Error Control for Internet Streaming and Multicast

    Directory of Open Access Journals (Sweden)

    Tianli Chu

    2003-01-01

    Full Text Available This paper proposes an integrated approach to Internet video streaming and multicast (e.g., receiver-driven layered multicast (RLM by McCanne based on combined wavelet video coding and error control. We design a packetized wavelet video (PWV coder to facilitate its integration with error control. The PWV coder produces packetized layered bitstreams that are independent among layers while being embedded within each layer. Thus, a lost packet only renders the following packets in the same layer useless. Based on the PWV coder, we search for a multilayered error-control strategy that optimally trades off source and channel coding for each layer under a given transmission rate to mitigate the effects of packet loss. While both the PWV coder and the error-control strategy are new—the former incorporates embedded wavelet video coding and packetization and the latter extends the single-layered approach for RLM by Chou et al.—the main distinction of this paper lies in the seamless integration of the two parts. Theoretical analysis shows a gain of up to 1 dB on a channel with 20% packet loss using our combined approach over separate designs of the source coder and the error-control mechanism. This is also substantiated by our simulations with a gain of up to 0.6 dB. In addition, our simulations show a gain of up to 2.2 dB over previous results reported by Chou et al.

  17. Readers, Players, and Watchers: EFL Students' Vocabulary Acquisition through Digital Video Games

    Science.gov (United States)

    Ebrahimzadeh, Mohsen

    2017-01-01

    The present study investigated vocabulary acquisition through a commercial digital video game compared to a traditional pencil-and-paper treatment. Chosen through cluster sampling, 241 male high school students (age 12-18) participated in the study. They were randomly assigned to one of the following groups. The first group, called Readers,…

  18. You are who you play you are : Modeling Player Traits from Video Game Behavior

    NARCIS (Netherlands)

    Tekofsky, Shoshannah

    2017-01-01

    You are who you play you are - especially when it comes to your age and your motivations. People say age is only a number, but it's a number we can guess pretty accurately from how someone plays video games. We find that younger people are favored by speed, while older people are favored by wisdom.

  19. A Survey of Video Game Players in a Public, Urban Research University

    Science.gov (United States)

    Thirunarayanan, M. O.; Vilchez, Manuel; Abreu, Liala; Ledesma, Cyntianna; Lopez, Sandra

    2010-01-01

    A survey was conducted in a public, research university located in a large and diverse metropolitan area in the southeastern part of the USA. The purpose of the survey was to determine both the positive and negative personal, educational, social, and work related consequences of playing video games. Nearly two-thirds of the 203 participants in…

  20. A Survey of Video Game Players in a Public, Urban Research University

    Science.gov (United States)

    Thirunarayanan, M. O.; Vilchez, Manuel; Abreu, Liala; Ledesma, Cyntianna; Lopez, Sandra

    2010-01-01

    A survey was conducted in a public, research university located in a large and diverse metropolitan area in the southeastern part of the USA. The purpose of the survey was to determine both the positive and negative personal, educational, social, and work related consequences of playing video games. Nearly two-thirds of the 203 participants in…

  1. Merge Frame Design for Video Stream Switching Using Piecewise Constant Functions

    Science.gov (United States)

    Dai, Wei; Cheung, Gene; Cheung, Ngai-Man; Ortega, Antonio; Au, Oscar C.

    2016-08-01

    The ability to efficiently switch from one pre-encoded video stream to another (e.g., for bitrate adaptation or view switching) is important for many interactive streaming applications. Recently, stream-switching mechanisms based on distributed source coding (DSC) have been proposed. In order to reduce the overall transmission rate, these approaches provide a "merge" mechanism, where information is sent to the decoder such that the exact same frame can be reconstructed given that any one of a known set of side information (SI) frames is available at the decoder (e.g., each SI frame may correspond to a different stream from which we are switching). However, the use of bit-plane coding and channel coding in many DSC approaches leads to complex coding and decoding. In this paper, we propose an alternative approach for merging multiple SI frames, using a piecewise constant (PWC) function as the merge operator. In our approach, for each block to be reconstructed, a series of parameters of these PWC merge functions are transmitted in order to guarantee identical reconstruction given the known side information blocks. We consider two different scenarios. In the first case, a target frame is first given, and then merge parameters are chosen so that this frame can be reconstructed exactly at the decoder. In contrast, in the second scenario, the reconstructed frame and merge parameters are jointly optimized to meet a rate-distortion criteria. Experiments show that for both scenarios, our proposed merge techniques can outperform both a recent approach based on DSC and the SP-frame approach in H.264, in terms of compression efficiency and decoder complexity.

  2. Earlier visual N1 latencies in expert video-game players: a temporal basis of enhanced visuospatial performance?

    Directory of Open Access Journals (Sweden)

    Andrew J Latham

    Full Text Available Increasing behavioural evidence suggests that expert video game players (VGPs show enhanced visual attention and visuospatial abilities, but what underlies these enhancements remains unclear. We administered the Poffenberger paradigm with concurrent electroencephalogram (EEG recording to assess occipital N1 latencies and interhemispheric transfer time (IHTT in expert VGPs. Participants comprised 15 right-handed male expert VGPs and 16 non-VGP controls matched for age, handedness, IQ and years of education. Expert VGPs began playing before age 10, had a minimum 8 years experience, and maintained playtime of at least 20 hours per week over the last 6 months. Non-VGPs had little-to-no game play experience (maximum 1.5 years. Participants responded to checkerboard stimuli presented to the left and right visual fields while 128-channel EEG was recorded. Expert VGPs responded significantly more quickly than non-VGPs. Expert VGPs also had significantly earlier occipital N1s in direct visual pathways (the hemisphere contralateral to the visual field in which the stimulus was presented. IHTT was calculated by comparing the latencies of occipital N1 components between hemispheres. No significant between-group differences in electrophysiological estimates of IHTT were found. Shorter N1 latencies may enable expert VGPs to discriminate attended visual stimuli significantly earlier than non-VGPs and contribute to faster responding in visual tasks. As successful video-game play requires precise, time pressured, bimanual motor movements in response to complex visual stimuli, which in this sample began during early childhood, these differences may reflect the experience and training involved during the development of video-game expertise, but training studies are needed to test this prediction.

  3. Earlier visual N1 latencies in expert video-game players: a temporal basis of enhanced visuospatial performance?

    Science.gov (United States)

    Latham, Andrew J; Patston, Lucy L M; Westermann, Christine; Kirk, Ian J; Tippett, Lynette J

    2013-01-01

    Increasing behavioural evidence suggests that expert video game players (VGPs) show enhanced visual attention and visuospatial abilities, but what underlies these enhancements remains unclear. We administered the Poffenberger paradigm with concurrent electroencephalogram (EEG) recording to assess occipital N1 latencies and interhemispheric transfer time (IHTT) in expert VGPs. Participants comprised 15 right-handed male expert VGPs and 16 non-VGP controls matched for age, handedness, IQ and years of education. Expert VGPs began playing before age 10, had a minimum 8 years experience, and maintained playtime of at least 20 hours per week over the last 6 months. Non-VGPs had little-to-no game play experience (maximum 1.5 years). Participants responded to checkerboard stimuli presented to the left and right visual fields while 128-channel EEG was recorded. Expert VGPs responded significantly more quickly than non-VGPs. Expert VGPs also had significantly earlier occipital N1s in direct visual pathways (the hemisphere contralateral to the visual field in which the stimulus was presented). IHTT was calculated by comparing the latencies of occipital N1 components between hemispheres. No significant between-group differences in electrophysiological estimates of IHTT were found. Shorter N1 latencies may enable expert VGPs to discriminate attended visual stimuli significantly earlier than non-VGPs and contribute to faster responding in visual tasks. As successful video-game play requires precise, time pressured, bimanual motor movements in response to complex visual stimuli, which in this sample began during early childhood, these differences may reflect the experience and training involved during the development of video-game expertise, but training studies are needed to test this prediction.

  4. The Virtual Threat Effect: A Test of Competing Explanations for the Effects of Racial Stereotyping in Video Games on Players' Cognitions.

    Science.gov (United States)

    Behm-Morawitz, Elizabeth; Hoffswell, Joseph; Chen, Szu-Wei

    2016-05-01

    Past research provides evidence that embodying a racially stereotyped African American video game character triggers stereotyped thinking among White players. However, the mechanisms through which virtual racial embodiment of a negatively stereotyped character in a video game impacts stereotyped thinking are still unknown. This study expands on past research and utilizes a between-subjects experimental design to test two possible theoretical explanations: the virtual threat effect and presence. On the one hand, embodying a negatively stereotyped African American character may elicit stereotyped thinking among White players due to the mere exposure to the threatening stereotype. According to this explanation, negative affective response to the threatening stimulus predicts stereotyping. On the other hand, the process of embodying, not just observing, the stereotyped African American character suggests that presence in the game may determine how impactful the game imagery is on White players' stereotyping of African Americans. In this case, level of presence would predict stereotyping. The findings of this study advance research by providing evidence of a psychological explanation for the negative effects of embodying a racially stereotyped video game character on players' race-related perceptions. We conceptualize the "virtual threat effect," which may be applied in additional contexts to understand how embodying stereotyped representations of outgroups in virtual environments may negatively affect individuals' perceptions and support of these groups.

  5. Robust and efficient fiducial tracking for augmented reality in HD-laparoscopic video streams

    Science.gov (United States)

    Mueller, M.; Groch, A.; Baumhauer, M.; Maier-Hein, L.; Teber, D.; Rassweiler, J.; Meinzer, H.-P.; Wegner, In.

    2012-02-01

    Augmented Reality (AR) is a convenient way of porting information from medical images into the surgical field of view and can deliver valuable assistance to the surgeon, especially in laparoscopic procedures. In addition, high definition (HD) laparoscopic video devices are a great improvement over the previously used low resolution equipment. However, in AR applications that rely on real-time detection of fiducials from video streams, the demand for efficient image processing has increased due to the introduction of HD devices. We present an algorithm based on the well-known Conditional Density Propagation (CONDENSATION) algorithm which can satisfy these new demands. By incorporating a prediction around an already existing and robust segmentation algorithm, we can speed up the whole procedure while leaving the robustness of the fiducial segmentation untouched. For evaluation purposes we tested the algorithm on recordings from real interventions, allowing for a meaningful interpretation of the results. Our results show that we can accelerate the segmentation by a factor of 3.5 on average. Moreover, the prediction information can be used to compensate for fiducials that are temporarily occluded or out of scope, providing greater stability.

  6. A QoE Aware Fairness Bi-level Resource Allocation Algorithm for Multiple Video Streaming in WLAN

    Directory of Open Access Journals (Sweden)

    Hu Zhou

    2015-11-01

    Full Text Available With the increasing of smart devices such as mobile phones and tablets, the scenario of multiple video users watching video streaming simultaneously in one wireless local area network (WLAN becomes more and more popular. However, the quality of experience (QoE and the fairness among multiple users are seriously impacted by the limited bandwidth and shared resources of WLAN. In this paper, we propose a novel bi-level resource allocation algorithm. To maximize the total throughput of the network, the WLAN is firstly tuned to the optimal operation point. Then the wireless resource is carefully allocated at the first level, i.e., between AP and uplink background traffic users, and the second level, i.e., among downlink video users. The simulation results show that the proposed algorithm can guarantee the QoE and the fairness for all the video users, and there is little impact on the average throughput of the background traffic users.

  7. Real-time Video-Streaming to Surgical Loupe Mounted Head-Up Display for Navigated Meningioma Resection.

    Science.gov (United States)

    Diaz, Roberto; Yoon, Jang; Chen, Robert; Quinones-Hinojosa, Alfredo; Wharen, Robert; Komotar, Ricardo

    2017-04-30

    Wearable technology interfaces with normal human movement and function, thereby enabling more efficient and adaptable use.We developed a wearable display system for use with intra-operative neuronavigation for brain tumor surgery. The Google glass head-up display system was adapted to surgical loupes with a video-streaming integrated hardware and software device for display of the Stealth S7 navigation screen. Phantom trials of surface ventriculostomy were performed. The device was utilized as an alternative display screen during cranial surgery. Image-guided brain tumor resection was accomplished using Google Glass head-up display of Stealth S7 navigation images. Visual display consists of navigation video-streaming over a wireless network. The integrated system developed for video-streaming permits video data display to the operating surgeon without requiring movement of the head away from the operative field. Google Glass head-up display can be used for intra-operative neuronavigation in the setting of intracranial tumor resection.

  8. Detailed Performance and Waiting-Time Predictability Analysis of Scheduling Options in On-Demand Video Streaming

    Directory of Open Access Journals (Sweden)

    Alsmirat MohammadA

    2010-01-01

    Full Text Available The number of on-demand video streams that can be supported concurrently is highly constrained by the stringent requirements of real-time playback and high transfer rates. To address this problem, stream merging techniques utilize the multicast facility to increase resource sharing. The achieved resource sharing depends greatly on how the waiting requests are scheduled for service. We investigate the effectiveness of the recently proposed cost-based scheduling in detail and analyze opportunities for further tunings and enhancements. In particular, we analyze alternative ways to compute the delivery cost. In addition, we propose a new scheduling policy, called Predictive Cost-Based Scheduling (PCS, which applies a prediction algorithm to predict future scheduling decisions and then uses the prediction results to potentially alter its current scheduling decisions. Moreover, we propose an enhancement technique, called Adaptive Regular Stream Triggering (ART, which significantly enhances stream merging behavior by selectively delaying the initiation of full-length video streams. We analyze the effectiveness of the proposed strategies in terms of their performance effectiveness and impacts on waiting-time predictability through extensive simulation. The results show that significant performance benefits as well as better waiting-time predictability can be attained.

  9. Acquisition of Streaming Live Online Video%流式在线直播视频的采集

    Institute of Scientific and Technical Information of China (English)

    薛莹莹

    2015-01-01

    针对由于流媒体协议的扩展性而带来的无法实时获取流媒体数据的问题,本文在深入分析流媒体传输原理的基础上,采用基于多核的包捕获技术,解决了流式在线直播视频数据的采集问题,为局域网内流式在线直播视频的实时接收和本地保存奠定了坚实的基础。%According to the problem that the expansion of streaming media protocol cannot obtain the real-time streaming media data,in this paper,based on the analysis of streaming media transmission principle,using the multi-core based packet capture technology,solves the problem of streaming live online video data acquisition, which has laid a solid foundation for real-time receiving and local store of local area network streaming online live video.

  10. Tunneling Horizontal IEC 61850 Traffic through Audio Video Bridging Streams for Flexible Microgrid Control and Protection

    Directory of Open Access Journals (Sweden)

    Michael Short

    2016-03-01

    Full Text Available In this paper, it is argued that some low-level aspects of the usual IEC 61850 mapping to Ethernet are not well suited to microgrids due to their dynamic nature and geographical distribution as compared to substations. It is proposed that the integration of IEEE time-sensitive networking (TSN concepts (which are currently implemented as audio video bridging (AVB technologies within an IEC 61850 / Manufacturing Message Specification framework provides a flexible and reconfigurable platform capable of overcoming such issues. A prototype test platform and bump-in-the-wire device for tunneling horizontal traffic through AVB are described. Experimental results are presented for sending IEC 61850 GOOSE (generic object oriented substation events and SV (sampled values messages through AVB tunnels. The obtained results verify that IEC 61850 event and sampled data may be reliably transported within the proposed framework with very low latency, even over a congested network. It is argued that since AVB streams can be flexibly configured from one or more central locations, and bandwidth reserved for their data ensuring predictability of delivery, this gives a solution which seems significantly more reliable than a pure MMS-based solution.

  11. Cross-layer ultrasound video streaming over mobile WiMAX and HSUPA networks.

    Science.gov (United States)

    Alinejad, Ali; Philip, Nada Y; Istepanian, Robert S H

    2012-01-01

    It is well known that the evolution of 4G-based mobile multimedia network systems will contribute significantly to future mobile healthcare (m-health) applications that require high bandwidth and fast data rates. Central to the success of such emerging applications is the compatibility of broadband networks, such as mobile Worldwide Interoperability For Microwave Access (WiMAX) and High-Speed Uplink Packet Access (HSUPA), and especially their rate adaption issues combined with the acceptable real-time medical quality of service requirements. In this paper, we address the relevant challenges of cross-layer design requirements for real-time rate adaptation of ultrasound video streaming in mobile WiMAX and HSUPA networks. A comparative performance analysis of such approach is validated in two experimental m-health test bed systems for both mobile WiMAX and HSUPA networks. The experimental results have shown an improved performance of mobile WiMAX compared to the HSUPA using the same cross-layer optimization approach.

  12. Fragility issues of medical video streaming over 802.11e-WLAN m-health environments.

    Science.gov (United States)

    Tan, Yow-Yiong Edwin; Philip, Nada; Istepanian, Robert H

    2006-01-01

    This paper presents some of the fragility issues of a medical video streaming over 802.11e-WLAN in m-health applications. In particular, we present a medical channel-adaptive fair allocation (MCAFA) scheme for enhanced QoS support for IEEE 802.11 (WLAN), as a modification for the standard 802.11e enhanced distributed coordination function (EDCF) is proposed for enhanced medical data performance. The medical channel-adaptive fair allocation (MCAFA) proposed extends the EDCF, by halving the contention window (CW) after zeta consecutive successful transmissions to reduce the collision probability when channel is busy. Simulation results show that MCAFA outperforms EDCF in-terms of overall performance relevant to the requirements of high throughput of medical data and video streaming traffic in 3G/WLAN wireless environments.

  13. Unequal Protection of Video Streaming through Adaptive Modulation with a Trizone Buffer over Bluetooth Enhanced Data Rate

    Directory of Open Access Journals (Sweden)

    Rouzbeh Razavi

    2007-12-01

    Full Text Available Bluetooth enhanced data rate wireless channel can support higher-quality video streams compared to previous versions of Bluetooth. Packet loss when transmitting compressed data has an effect on the delivered video quality that endures over multiple frames. To reduce the impact of radio frequency noise and interference, this paper proposes adaptive modulation based on content type at the video frame level and content importance at the macroblock level. Because the bit rate of protected data is reduced, the paper proposes buffer management to reduce the risk of buffer overflow. A trizone buffer is introduced, with a varying unequal protection policy in each zone. Application of this policy together with adaptive modulation results in up to 4 dB improvement in objective video quality compared to fixed rate scheme for an additive white Gaussian noise channel and around 10 dB for a Gilbert-Elliott channel. The paper also reports a consistent improvement in video quality over a scheme that adapts to channel conditions by varying the data rate without accounting for the video frame packet type or buffer congestion.

  14. P2P在线视频研究综述%Survey on P2P video streaming systems

    Institute of Scientific and Technical Information of China (English)

    李真真; 张志斌; 杜跃进

    2009-01-01

    P2P技术凭借其开放性、可扩展性和高性价比等优点成为了目前解决在线视频问题的有效手段之一.虽然P2P技术在文件共享和IP语音等方面的应用已经基本趋于成熟,但其在在线视频领域的应用尚处于起步阶段,还面临着许多需要解决的问题.对P2P在线视频进行了全面而深入的分析,首先介绍了网络广播分类及体系结构设计,整理和总结了已有的关于P2P在线视频系统的测量研究结果,最后对于P2P在线视频信任和污染攻击等安全问题进行了概述.%P2P technology has become one of the most effective approaches to internet video broadcast for its simple deployment, good scalability and high cost-effectiveness ratio. P2P applications such as file download and voice over IP have gained tremendous popularity, while video broadcast is still in its early stage and there are a number of key technical challenges that need to be overcome. This paper provided a comprehensive and in-depth analysis of the P2P video streaming, and discussed the characteristics of video broadcast applications and reviewed the approaches to video streaming systems architecture design. After surveying the results of measurement studied on P2P video streaming systems, then the paper overviewed security aspects of P2P live video streaming systems such as pollution attack and DoS attack.

  15. Three distinct mechanisms predominate in non-contact anterior cruciate ligament injuries in male professional football players: a systematic video analysis of 39 cases

    Science.gov (United States)

    Waldén, Markus; Krosshaug, Tron; Bjørneboe, John; Andersen, Thor Einar; Faul, Oliver

    2015-01-01

    Background Current knowledge on anterior cruciate ligament (ACL) injury mechanisms in male football players is limited. Aim To describe ACL injury mechanisms in male professional football players using systematic video analysis. Methods We assessed videos from 39 complete ACL tears recorded via prospective professional football injury surveillance between 2001 and 2011. Five analysts independently reviewed all videos to estimate the time of initial foot contact with the ground and the time of ACL tear. We then analysed all videos according to a structured format describing the injury circumstances and lower limb joint biomechanics. Results Twenty-five injuries were non-contact, eight indirect contact and six direct contact injuries. We identified three main categories of non-contact and indirect contact injury situations: (1) pressing (n=11), (2) re-gaining balance after kicking (n=5) and (3) landing after heading (n=5). The fourth main injury situation was direct contact with the injured leg or knee (n=6). Knee valgus was frequently seen in the main categories of non-contact and indirect contact playing situations (n=11), but a dynamic valgus collapse was infrequent (n=3). This was in contrast to the tackling-induced direct contact situations where a knee valgus collapse occurred in all cases (n=3). Conclusions Eighty-five per cent of the ACL injuries in male professional football players resulted from non-contact or indirect contact mechanisms. The most common playing situation leading to injury was pressing followed by kicking and heading. Knee valgus was frequently seen regardless of the playing situation, but a dynamic valgus collapse was rare. PMID:25907183

  16. Our experiences with development of digitised video streams and their use in animal-free medical education.

    Science.gov (United States)

    Cervinka, Miroslav; Cervinková, Zuzana; Novák, Jan; Spicák, Jan; Rudolf, Emil; Peychl, Jan

    2004-06-01

    Alternatives and their teaching are an essential part of the curricula at the Faculty of Medicine. Dynamic screen-based video recordings are the most important type of alternative models employed for teaching purposes. Currently, the majority of teaching materials for this purpose are based on PowerPoint presentations, which are very popular because of their high versatility and visual impact. Furthermore, current developments in the field of image capturing devices and software enable the use of digitised video streams, tailored precisely to the specific situation. Here, we demonstrate that with reasonable financial resources, it is possible to prepare video sequences and to introduce them into the PowerPoint presentation, thereby shaping the teaching process according to individual students' needs and specificities.

  17. HLS-SHARE:A PLAYER MIDDLEWARE TIMELY SHARING HTTP LIVE STREAMING%HLS-Share:一种实时分享Http Live Streaming的播放器中间件

    Institute of Scientific and Technical Information of China (English)

    郑博玮; 权恒星; 刘磊; 孙毅

    2014-01-01

    描述一种分享Http Live Streaming流媒体,同时对服务器和播放器透明的播放器中间件HLS-Share。HLS-Share通过手机节点间的协作计算,使手机共享3G网络带宽,减少3G网络流量,加速观看Http Live Streaming流。HLS-Share采用基于事件驱动的方法在本地P2P网络中挑选部分节点作为中继节点负责分享从Internet获取的Http Live Streaming流。通过实验验证了相比于每部手机独立使用3 G网络观看视频,HLS-Share在引入极小的CPU使用率的代价下,能够实现共享带宽、加快缓存速度的作用,并且消耗的电量小于前者。%This paper describes a player middleware named as HLS-Share,it shares streaming media of Http Live Streaming,and is transparent to both the server and the player simultaneously.HLS-Share enables mobile phones nodes share their 3G networks bandwidth and cut down 3G networks flow by cooperated computation between the mobile phones’nodes,which speeds up Http Live Streaming watching. HLS-Share selects part of the nodes from local P2P network by using event-driven based means and employs them as the relay nodes in charge of sharing the Http Live Streaming data obtained from Internet.In this paper we verify through the experiment that comparing with each mobile phone watching video in 3G network independently,HLS-Share is able to realise bandwidth sharing,accelerate the role of cache speed,and has less power consumption than the former at the cost of introducing slight CPU utilisation rate.

  18. MATIN: a random network coding based framework for high quality peer-to-peer live video streaming.

    Science.gov (United States)

    Barekatain, Behrang; Khezrimotlagh, Dariush; Aizaini Maarof, Mohd; Ghaeini, Hamid Reza; Salleh, Shaharuddin; Quintana, Alfonso Ariza; Akbari, Behzad; Cabrera, Alicia Triviño

    2013-01-01

    In recent years, Random Network Coding (RNC) has emerged as a promising solution for efficient Peer-to-Peer (P2P) video multicasting over the Internet. This probably refers to this fact that RNC noticeably increases the error resiliency and throughput of the network. However, high transmission overhead arising from sending large coefficients vector as header has been the most important challenge of the RNC. Moreover, due to employing the Gauss-Jordan elimination method, considerable computational complexity can be imposed on peers in decoding the encoded blocks and checking linear dependency among the coefficients vectors. In order to address these challenges, this study introduces MATIN which is a random network coding based framework for efficient P2P video streaming. The MATIN includes a novel coefficients matrix generation method so that there is no linear dependency in the generated coefficients matrix. Using the proposed framework, each peer encapsulates one instead of n coefficients entries into the generated encoded packet which results in very low transmission overhead. It is also possible to obtain the inverted coefficients matrix using a bit number of simple arithmetic operations. In this regard, peers sustain very low computational complexities. As a result, the MATIN permits random network coding to be more efficient in P2P video streaming systems. The results obtained from simulation using OMNET++ show that it substantially outperforms the RNC which uses the Gauss-Jordan elimination method by providing better video quality on peers in terms of the four important performance metrics including video distortion, dependency distortion, End-to-End delay and Initial Startup delay.

  19. MATIN: a random network coding based framework for high quality peer-to-peer live video streaming.

    Directory of Open Access Journals (Sweden)

    Behrang Barekatain

    Full Text Available In recent years, Random Network Coding (RNC has emerged as a promising solution for efficient Peer-to-Peer (P2P video multicasting over the Internet. This probably refers to this fact that RNC noticeably increases the error resiliency and throughput of the network. However, high transmission overhead arising from sending large coefficients vector as header has been the most important challenge of the RNC. Moreover, due to employing the Gauss-Jordan elimination method, considerable computational complexity can be imposed on peers in decoding the encoded blocks and checking linear dependency among the coefficients vectors. In order to address these challenges, this study introduces MATIN which is a random network coding based framework for efficient P2P video streaming. The MATIN includes a novel coefficients matrix generation method so that there is no linear dependency in the generated coefficients matrix. Using the proposed framework, each peer encapsulates one instead of n coefficients entries into the generated encoded packet which results in very low transmission overhead. It is also possible to obtain the inverted coefficients matrix using a bit number of simple arithmetic operations. In this regard, peers sustain very low computational complexities. As a result, the MATIN permits random network coding to be more efficient in P2P video streaming systems. The results obtained from simulation using OMNET++ show that it substantially outperforms the RNC which uses the Gauss-Jordan elimination method by providing better video quality on peers in terms of the four important performance metrics including video distortion, dependency distortion, End-to-End delay and Initial Startup delay.

  20. Video in Distance Education: ITFS vs. Web-Streaming--Evaluation of Student Attitudes

    Science.gov (United States)

    Reisslein, Jana; Seeling, Patrick; Reisslein, Martin

    2005-01-01

    The use of video in distance education courses has a long tradition, with many colleges and universities having been delivering distance education courses with video since the 80's using the Instructional Television Fixed Service (ITFS) and cable television. With the emergence of the Internet and the increased access bandwidths from private homes…

  1. A RANDOMIZED SELECTIVE ENCRYPTION USING HASHING TECHNIQUE FOR SECURING VIDEO STREAMS

    Directory of Open Access Journals (Sweden)

    Lizyflorance. C

    2012-11-01

    Full Text Available Digital video transmissions are widely used in network nowadays. Hence, securing its contents and keeping privacy is vital. Several encryption algorithms have been proposed earlier to achieve securevideo transmission. But altogether attaining efficiency, security and flexibility is a major challenge. To transmit a digital video, encryption is necessary to protect its contents from attacks. As the size of the videos are usually large their contents has to be compressed before transmission. Encryption is applied on the video content after compression. One of the encryption technique selective encryption is used for encrypting video. It encrypts only a subset of data. The selective encryption algorithm reduces the amount of the data to be encrypted and achieves a required level of security. In this paper we study the existing selective encryption algorithm and its classifications. The challenges in the selective encryptionalgorithms and some future directions are presented.

  2. Dashboard Videos

    Science.gov (United States)

    Gleue, Alan D.; Depcik, Chris; Peltier, Ted

    2012-01-01

    Last school year, I had a web link emailed to me entitled "A Dashboard Physics Lesson." The link, created and posted by Dale Basier on his "Lab Out Loud" blog, illustrates video of a car's speedometer synchronized with video of the road. These two separate video streams are compiled into one video that students can watch and analyze. After seeing…

  3. Optimal JPWL Forward Error Correction Rate Allocation for Robust JPEG 2000 Images and Video Streaming over Mobile Ad Hoc Networks

    Science.gov (United States)

    Agueh, Max; Diouris, Jean-François; Diop, Magaye; Devaux, François-Olivier; De Vleeschouwer, Christophe; Macq, Benoit

    2008-12-01

    Based on the analysis of real mobile ad hoc network (MANET) traces, we derive in this paper an optimal wireless JPEG 2000 compliant forward error correction (FEC) rate allocation scheme for a robust streaming of images and videos over MANET. The packet-based proposed scheme has a low complexity and is compliant to JPWL, the 11th part of the JPEG 2000 standard. The effectiveness of the proposed method is evaluated using a wireless Motion JPEG 2000 client/server application; and the ability of the optimal scheme to guarantee quality of service (QoS) to wireless clients is demonstrated.

  4. Optimal JPWL Forward Error Correction Rate Allocation for Robust JPEG 2000 Images and Video Streaming over Mobile Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Benoit Macq

    2008-07-01

    Full Text Available Based on the analysis of real mobile ad hoc network (MANET traces, we derive in this paper an optimal wireless JPEG 2000 compliant forward error correction (FEC rate allocation scheme for a robust streaming of images and videos over MANET. The packet-based proposed scheme has a low complexity and is compliant to JPWL, the 11th part of the JPEG 2000 standard. The effectiveness of the proposed method is evaluated using a wireless Motion JPEG 2000 client/server application; and the ability of the optimal scheme to guarantee quality of service (QoS to wireless clients is demonstrated.

  5. How to design and develop There App: A mobile app focused on live video streaming, promoting new social interactions

    OpenAIRE

    Farrancha, Miguel Francisco Pires

    2015-01-01

    This work project aims to demonstrate how to design and develop an innovative concept of video streaming app. The project combines technology push and market pull theories into developing a product that is more suitable for the customer needs, with the particularity that there is no other way of seeing any place in the world, live and ondemand. An analysis on the bigger influencers in terms of design-thinking and new product development, as Tim Brown or Paul Trott, lead to a be...

  6. Publicación de materiales audiovisuales a través de un servidor de video-streaming Publication of audio-visual materials through a streaming video server

    Directory of Open Access Journals (Sweden)

    Acevedo Clavijo Edwin Jovanny

    2010-07-01

    Full Text Available Esta propuesta tiene como objetivo estudiar varias alternativas de servidores Streaming para determinar la mejor herramienta para el desarrollo de la publicación de material audiovisual educativo. Se evaluaron las plataformas más utilizadas teniendo en cuenta sus características y beneficios que tiene cada servidor entre las los cuales están: Hélix Universal Server, Windows Media Server de Microsoft, Peer Cast y Darwin Server. implementando un servidor con mayores capacidades y beneficios para la publicación de videos con fines académicos a través de la intranet de la Universidad Cooperativa de Colombia seccional Barrancabermeja This proposal has as an principal objective to study different alternatives for streaming servers to determine the best tool in the project’s development. Platforms most used were evaluated features and benefits in each served such as: Helix Universal Server, Microsoft Windows Media Server, Peer Cast and Darwin Server. Implementing a server with more capabilities and benefits for the publication of videos for academic purposes through the intranet of the Cooperative University of Colombia Barrancabermeja’s sectional

  7. Digital Video taken during the 3-person submersible Clelia dive 609 of the NOAA Office of Ocean Exploration's Islands in the Stream 2001 cruise, August 30, 2001 (NCEI Accession 0037122)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The video data in this accession was captured during the Islands in the Stream mission of 2001. Islands in the Stream was a three-month scientific expedition to...

  8. Digital video taken during the 3-person submersible Clelia dive 606 of the NOAA Office of Ocean Exploration's Islands in the Stream 2001 cruise, August 29, 2001 (NCEI Accession 0039739)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The video data in this accession was captured during the Islands in the Stream mission of 2001. Islands in the Stream was a three-month scientific expedition to...

  9. Subjective Quality Assessment of H.264/AVC Video Streaming with Packet Losses

    Directory of Open Access Journals (Sweden)

    Naccari Matteo

    2011-01-01

    Full Text Available Research in the field of video quality assessment relies on the availability of subjective scores, collected by means of experiments in which groups of people are asked to rate the quality of video sequences. The availability of subjective scores is fundamental to enable validation and comparative benchmarking of the objective algorithms that try to predict human perception of video quality by automatically analyzing the video sequences, in a way to support reproducible and reliable research results. In this paper, a publicly available database of subjective quality scores and corrupted video sequences is described. The scores refer to 156 sequences at CIF and 4CIF spatial resolutions, encoded with H.264/AVC and corrupted by simulating the transmission over an error-prone network. The subjective evaluation has been performed by 40 subjects at the premises of two academic institutions, in standard-compliant controlled environments. In order to support reproducible research in the field of full-reference, reduced-reference, and no-reference video quality assessment algorithms, both the uncompressed files and the H.264/AVC bitstreams, as well as the packet loss patterns, have been made available to the research community.

  10. System architecture for ubiquitous live video streaming in university network environment

    CSIR Research Space (South Africa)

    Dludla, AG

    2013-09-01

    Full Text Available an architecture which supports ubiquitous live streaming for university or campus networks using a modified bluetooth inquiry mechanism with extended ID, integrated end-user device usage and adaptation to heterogeneous networks. Riding on that architecture...

  11. Streaming weekly soap opera video episodes to smartphones in a randomized controlled trial to reduce HIV risk in young urban African American/black women.

    Science.gov (United States)

    Jones, Rachel; Lacroix, Lorraine J

    2012-07-01

    Love, Sex, and Choices is a 12-episode soap opera video series created as an intervention to reduce HIV sex risk. The effect on women's HIV risk behavior was evaluated in a randomized controlled trial in 238 high risk, predominately African American young adult women in the urban Northeast. To facilitate on-demand access and privacy, the episodes were streamed to study-provided smartphones. Here, we discuss the development of a mobile platform to deliver the 12-weekly video episodes or weekly HIV risk reduction written messages to smartphones, including; the technical requirements, development, and evaluation. Popularity of the smartphone and use of the Internet for multimedia offer a new channel to address health disparities in traditionally underserved populations. This is the first study to report on streaming a serialized video-based intervention to a smartphone. The approach described here may provide useful insights in assessing advantages and disadvantages of smartphones to implement a video-based intervention.

  12. Correlation between two-dimensional video analysis and subjective assessment in evaluating knee control among elite female team handball players

    DEFF Research Database (Denmark)

    Stensrud, Silje; Myklebust, Grethe; Kristianslund, Eirik

    2011-01-01

    Poor frontal plane knee control has been shown to be a risk factor for anterior cruciate ligament injuries in ball/team sports. It is necessary to develop simple tests that can identify players with poor knee control and among other factors be able to optimise preventive training programmes...

  13. Low Delay Video Streaming on the Internet of Things Using Raspberry Pi

    OpenAIRE

    Ulf Jennehag; Stefan Forsstrom; Federico V. Fiordigigli

    2016-01-01

    The Internet of Things is predicted to consist of over 50 billion devices aiming to solve problems in most areas of our digital society. A large part of the data communicated is expected to consist of various multimedia contents, such as live audio and video. This article presents a solution for the communication of high definition video in low-delay scenarios (<200 ms) under the constraints of devices with limited hardware resources, such as the Raspberry Pi. We verify that it is possible...

  14. Low Delay Video Streaming on the Internet of Things Using Raspberry Pi

    OpenAIRE

    Ulf Jennehag; Stefan Forsstrom; Federico V. Fiordigigli

    2016-01-01

    The Internet of Things is predicted to consist of over 50 billion devices aiming to solve problems in most areas of our digital society. A large part of the data communicated is expected to consist of various multimedia contents, such as live audio and video. This article presents a solution for the communication of high definition video in low-delay scenarios (<200 ms) under the constraints of devices with limited hardware resources, such as the Raspberry Pi. We verify that it is possible...

  15. Power-Constrained Fuzzy Logic Control of Video Streaming over a Wireless Interconnect

    Directory of Open Access Journals (Sweden)

    Mohammed Ghanbari

    2008-06-01

    Full Text Available Wireless communication of video, with Bluetooth as an example, represents a compromise between channel conditions, display and decode deadlines, and energy constraints. This paper proposes fuzzy logic control (FLC of automatic repeat request (ARQ as a way of reconciling these factors, with a 40% saving in power in the worst channel conditions from economizing on transmissions when channel errors occur. Whatever the channel conditions are, FLC is shown to outperform the default Bluetooth scheme and an alternative Bluetooth-adaptive ARQ scheme in terms of reduced packet loss and delay, as well as improved video quality.

  16. Remote stereoscopic video play platform for naked eyes based on the Android system

    Science.gov (United States)

    Jia, Changxin; Sang, Xinzhu; Liu, Jing; Cheng, Mingsheng

    2014-11-01

    As people's life quality have been improved significantly, the traditional 2D video technology can not meet people's urgent desire for a better video quality, which leads to the rapid development of 3D video technology. Simultaneously people want to watch 3D video in portable devices,. For achieving the above purpose, we set up a remote stereoscopic video play platform. The platform consists of a server and clients. The server is used for transmission of different formats of video and the client is responsible for receiving remote video for the next decoding and pixel restructuring. We utilize and improve Live555 as video transmission server. Live555 is a cross-platform open source project which provides solutions for streaming media such as RTSP protocol and supports transmission of multiple video formats. At the receiving end, we use our laboratory own player. The player for Android, which is with all the basic functions as the ordinary players do and able to play normal 2D video, is the basic structure for redevelopment. Also RTSP is implemented into this structure for telecommunication. In order to achieve stereoscopic display, we need to make pixel rearrangement in this player's decoding part. The decoding part is the local code which JNI interface calls so that we can extract video frames more effectively. The video formats that we process are left and right, up and down and nine grids. In the design and development, a large number of key technologies from Android application development have been employed, including a variety of wireless transmission, pixel restructuring and JNI call. By employing these key technologies, the design plan has been finally completed. After some updates and optimizations, the video player can play remote 3D video well anytime and anywhere and meet people's requirement.

  17. Video demystified

    CERN Document Server

    Jack, Keith

    2004-01-01

    This international bestseller and essential reference is the "bible" for digital video engineers and programmers worldwide. This is by far the most informative analog and digital video reference available, includes the hottest new trends and cutting-edge developments in the field. Video Demystified, Fourth Edition is a "one stop" reference guide for the various digital video technologies. The fourth edition is completely updated with all new chapters on MPEG-4, H.264, SDTV/HDTV, ATSC/DVB, and Streaming Video (Video over DSL, Ethernet, etc.), as well as discussions of the latest standards throughout. The accompanying CD-ROM is updated to include a unique set of video test files in the newest formats. *This essential reference is the "bible" for digital video engineers and programmers worldwide *Contains all new chapters on MPEG-4, H.264, SDTV/HDTV, ATSC/DVB, and Streaming Video *Completely revised with all the latest and most up-to-date industry standards.

  18. 基于GPU的视频流拼接算法研究%Research of video stream splicing algorithm based on GPU

    Institute of Scientific and Technical Information of China (English)

    张燕; 赵新灿; 谭同德

    2012-01-01

    To solve the stability and real-time of video stream splicing, combined with the powerful graphics processor GPU's parallel computing capabilities, a design method of stream splicing algorithm based on GPU is presented Extracting video stream frame image, then image stitching which contains feature extraction and matching is implemented on the GPU using SIFT (scale invariant feature transform) algorithm, to realize the stable and real-time video stream splicing. The SIFT algorithm based on the GPU makes full use of the GPU's parallel processing capability, which accelerates the implementation of video streaming stitching algorithm and realizes the fast and stable video stream splicing with quite different but a public vision.%为解决视频流的稳定实时拼接,结合图形处理器GPU强大的并行计算能力,提出了一种基于GPU的视频流拼接算法.提取视频流的帧图像,利用尺度不变特征变换(scale invariant feature transform,SIFT)算法在GPU上实现帧图像的特征提取与匹配,实现图像拼接,进而实现视频流的稳定实时拼接.基于GPU的SIFT算法充分利用了GPU的并行处理能力,加快了视频流拼接算法执行的速度,真正意义上实现了几个差异较大但具有公共视野的视频流快速稳定的拼接.

  19. Video classification for video quality prediction

    Institute of Scientific and Technical Information of China (English)

    LIU Yu-xin; KURCEREN Ragip; BUDHIA Udit

    2006-01-01

    In this paper we propose a novel method for video quality prediction using video classification. In essence, our approach can serve two goals: (1) To measure the video quality of compressed video sequences without referencing to the original uncompressed videos, i.e., to realize No-Reference (NR) video quality evaluation; (2) To predict quality scores for uncompressed video sequences at various bitrates without actually encoding them. The use of our approach can help realize video streaming with ideal Quality of Service (QoS). Our approach is a low complexity solution, which is specially suitable for application to mobile video streaming where the resources at the handsets are scarce.

  20. Evaluating the Use of Streaming Video To Support Student Learning in a First-Year Life Sciences Course for Student Nurses.

    Science.gov (United States)

    Green, Sue M.; Voegeli, David; Harrison, Maureen; Phillips, Jackie; Knowles, Jess; Weaver, Mike; Shepard, Kerry

    2003-01-01

    Nursing students (n=656) used streaming videos on immune, endocrine, and neurological systems using Blackboard software. Of students who viewed all three, 32% found access easy, 59% enjoyed them, and 25% felt very confident in their learning. Results were consistent across three different types and embedding methods. Technical and access problems…

  1. Learner Outcomes and Satisfaction: A Comparison of Live Video-Streamed Instruction, Satellite Broadcast Instruction, and Face-to-Face Instruction

    Science.gov (United States)

    Abdous, M'hammed; Yoshimura, Miki

    2010-01-01

    This study examined the final grade and satisfaction level differences among students taking specific courses using three different methods: face-to-face in class, via satellite broadcasting at remote sites, and via live video-streaming at home or at work. In each case, the same course was taught by the same instructor in all three delivery…

  2. A Format-Compliant Selective Encryption Scheme for Real-Time Video Streaming of the H.264/AVC

    Directory of Open Access Journals (Sweden)

    Fatma SBIAA

    2016-04-01

    Full Text Available H.264 video coding standard is one of the most promising techniques for the future video communications. In fact, it supports a broad range of applications. Accordingly, with the continuous promotion of multimedia services, H.264 has been widely used in real-world applications. A major concern in the design of H.264 encryption algorithms is how to achieve a sufficiently high security level, while maintaining the efficiency of the underlying compression process. In this paper a new selective encryption scheme for the H.264 standard is presented. The aim of this work is to study the security of the H.264 standard in order to propose the appropriate design of a hardware crypto-processor based on a stream cipher algorithm. Since the proposed cryptosystem is mainly dedicated to the multimedia applications, it provides multiple security levels in order to satisfy the requirements of various applications for different purposes while ensuring higher coding efficiency. Different performance analyses were made in order to evaluate the new encryption system. The experimental results showed the reliability and the robustness of the proposed technique.

  3. Cross-Layer Measurement on an IEEE 802.11g Wireless Network Supporting MPEG-2 Video Streaming Applications in the Presence of Interference

    Directory of Open Access Journals (Sweden)

    Alessandro Sona

    2010-01-01

    Full Text Available The performance of wireless local area networks supporting video streaming applications, based on MPEG-2 video codec, in the presence of interference is here dealt with. IEEE 802.11g standard wireless networks, that do not support QoS in according with IEEE 802.11e standard, are, in particular, accounted for and Bluetooth signals, additive white Gaussian noise, and competitive data traffic are considered as sources of interference. The goal is twofold: from one side, experimentally assessing and correlating the values that some performance metrics assume at the same time at different layers of an IEEE 802.11g WLAN delivering video streaming in the presence of in-channel interference; from the other side, deducing helpful and practical hints for designers and technicians, in order to efficiently assess and enhance the performance of an IEEE 802.11g WLAN supporting video streaming in some suitable setup conditions and in the presence of interference. To this purpose, an experimental analysis is planned following a cross-layer measurement approach, and a proper testbed within a semianechoic chamber is used. Valuable results are obtained in terms of signal-to-interference ratio, packet loss ratio, jitter, video quality, and interference data rate; helpful hints for designers and technicians are finally gained.

  4. Video Game Violence and the Female Game Player: Self- and Opponent Gender Effects on Presence and Aggressive Thoughts

    Science.gov (United States)

    Eastin, Matthew S.

    2006-01-01

    Adding depth and breadth to the general aggression model, this paper presents three experiments that test the relationships among user and opponent gender representation, opponent type, presence, and aggressive thoughts from violent video game play. Studies 1 and 2 suggest that females experience greater presence and more aggressive thoughts from…

  5. Live-streaming: Time-lapse video evidence of novel streamer formation mechanism and varying viscosity.

    Science.gov (United States)

    Parvinzadeh Gashti, Mazeyar; Bellavance, Julien; Kroukamp, Otini; Wolfaardt, Gideon; Taghavi, Seyed Mohammad; Greener, Jesse

    2015-07-01

    Time-lapse videos of growing biofilms were analyzed using a background subtraction method, which removed camouflaging effects from the heterogeneous field of view to reveal evidence of streamer formation from optically dense biofilm segments. In addition, quantitative measurements of biofilm velocity and optical density, combined with mathematical modeling, demonstrated that streamer formation occurred from mature, high-viscosity biofilms. We propose a streamer formation mechanism by sudden partial detachment, as opposed to continuous elongation as observed in other microfluidic studies. Additionally, streamer formation occurred in straight microchannels, as opposed to serpentine or pseudo-porous channels, as previously reported.

  6. An Innovative Streaming Video System With a Point-of-View Head Camera Transmission of Surgeries to Smartphones and Tablets: An Educational Utility.

    Science.gov (United States)

    Chaves, Rafael Oliveira; de Oliveira, Pedro Armando Valente; Rocha, Luciano Chaves; David, Joacy Pedro Franco; Ferreira, Sanmari Costa; Santos, Alex de Assis Santos Dos; Melo, Rômulo Müller Dos Santos; Yasojima, Edson Yuzur; Brito, Marcus Vinicius Henriques

    2017-10-01

    In order to engage medical students and residents from public health centers to utilize the telemedicine features of surgery on their own smartphones and tablets as an educational tool, an innovative streaming system was developed with the purpose of streaming live footage from open surgeries to smartphones and tablets, allowing the visualization of the surgical field from the surgeon's perspective. The current study aims to describe the results of an evaluation on level 1 of Kirkpatrick's Model for Evaluation of the streaming system usage during gynecological surgeries, based on the perception of medical students and gynecology residents. Consisted of a live video streaming (from the surgeon's point of view) of gynecological surgeries for smartphones and tablets, one for each volunteer. The volunteers were able to connect to the local wireless network, created by the streaming system, through an access password and watch the video transmission on a web browser on their smartphones. Then, they answered a Likert-type questionnaire containing 14 items about the educational applicability of the streaming system, as well as comparing it to watching an in loco procedure. This study is formally approved by the local ethics commission (Certificate No. 53175915.7.0000.5171/2016). Twenty-one volunteers participated, totalizing 294 items answered, in which 94.2% were in agreement with the items affirmative, 4.1% were neutral, and only 1.7% answers corresponded to negative impressions. Cronbach's α was .82, which represents a good reliability level. Spearman's coefficients were highly significant in 4 comparisons and moderately significant in the other 20 comparisons. This study presents a local streaming video system of live surgeries to smartphones and tablets and shows its educational utility, low cost, and simple usage, which offers convenience and satisfactory image resolution, thus being potentially applicable in surgical teaching.

  7. Advertising product improvement opportunities using segmentation in Video-on-Demand services : A case study of MTG’s opportunities in the shift from television to streaming video

    OpenAIRE

    Kohlberg, Marcus; Westman, Lars-Peter

    2014-01-01

    More and more people choose to watch television online through online video-on- demand services. For media corporations, such as the Modern Times Group (MTG), this means that video-on-demand will become an increasingly important source of revenue. Because video-on-demand is an online service, advertising products offered therein are in competition with other online advertising products. Currently, MTG’s video-on-demand advertising products are the same as on regular television, meaning they h...

  8. STREAM

    DEFF Research Database (Denmark)

    Godsk, Mikkel

    This paper presents a flexible model, ‘STREAM’, for transforming higher science education into blended and online learning. The model is inspired by ideas of active and collaborative learning and builds on feedback strategies well-known from Just-in-Time Teaching, Flipped Classroom, and Peer...... Instruction. The aim of the model is to provide both a concrete and comprehensible design toolkit for adopting and implementing educational technologies in higher science teaching practice and at the same time comply with diverse ambitions. As opposed to the above-mentioned feedback strategies, the STREAM...

  9. A QoE study of different stream and layout configurations in video conferencing under limited network conditions

    NARCIS (Netherlands)

    Gunkel, S.; Schmitt, M.R.; Cesar Garcia, P.S.

    2015-01-01

    One particular problem of QoE research in video conferencing is, that most research in the past concentrated on one-to-one video conferencing or simply video consumption. However, video conferencing with two people (one-to-one) and within a group (multi-party) is different. Particularly, limitations

  10. 基于流媒体的天气预报电视会商VOD系统设计%Design of Video on Demand System for Weather-forcast Video Conference Based on Streaming Media Technology

    Institute of Scientific and Technical Information of China (English)

    刘红梅; 李春来; 陈永涛; 黄珣

    2013-01-01

    The Video on Demand (VOD) system for weather-forcast video conference of CMA is designed based on the implementpoints of streaming technology,and it's described in details about streaming media structure,system configuration structure,software process.The main points in system implementation such as concurrent client number,distributed stream-type,signal synchronizationare analyzed thoroughly.So the multi-video signals can be captured and transferred well for the live &on-demand broadcast and download in the system,and video & VGA dual-signals can be played and controlled especially in one screen display with synchronization.The result shows the system can work steadily to expand effectively the service domain of video conference,and much help can be provided for weather-forcast operation.%结合流媒体技术实施要点,设计了中国气象局天气预报电视会商VOD系统,并对系统的流媒体架构、系统配置架构、软件流程等进行了详细说明.深入分析了系统实施的技术要点,如并发客户端数、流发布类型、信号同步等,设计的系统实现了多路视频信号的采集、上传、直播、点播、下载功能等,特别是视频流和VGA流双路信号的同步、同屏、可控播放.通过实际运行验证,系统运行稳定,有效拓展了电视会商系统的服务范围,有助于天气预报业务的发展.

  11. Analyzing Video Streaming Quality by Using Various Error Correction Methods on Mobile Ad hoc Networks in NS2

    Directory of Open Access Journals (Sweden)

    Norrozila Sulaiman

    2014-10-01

    Full Text Available Transmission video over ad hoc networks has become one of the most important and interesting subjects of study for researchers and programmers because of the strong relationship between video applications and frequent users of various mobile devices, such as laptops, PDAs, and mobile phones in all aspects of life. However, many challenges, such as packet loss, congestion (i.e., impairments at the network layer, multipath fading (i.e., impairments at the physical layer [1], and link failure, exist in transferring video over ad hoc networks; these challenges negatively affect the quality of the perceived video [2].This study has investigated video transfer over ad hoc networks. The main challenges of transferring video over ad hoc networks as well as types of errors that may occur during video transmission, various types of video mechanisms, error correction methods, and different Quality of Service (QoS parameters that affect the quality of the received video are also investigated.

  12. Design of Secure Video Stream Transmission System Based on Gstreamer%基于Gstreamer的安全视频流传输系统的实现

    Institute of Scientific and Technical Information of China (English)

    宫健; 吴蒙

    2016-01-01

    In this paper,a security video stream transmission system based on PandaBoard ES and Gstreamer platform is designed. In the system,V4L2 framework is used for collecting video source and H. 264 compression coding technology is used for encoding the video stream. In terms of transmission,RTP is used to ensure good real-time performance. Last but not least,the AES encryption algorithm is also adopted to guarantee the security of the video data. The implementation of real-time video transmission system is comprehensively shown in this paper and through the analysis of the data acquired in the experiment. It is found that clients can receive the live video stream collected by the server timely,accurately and safely,which means that the secure video stream transmission system described in this paper is real-time,accurate,stable and secure.%文中设计并实现了一种基于PandaBoard ES硬件平台和Gstreamer开发框架的安全视频流传输系统。在系统中使用了V4L2视频采集框架、H.264压缩编码技术、RTP流媒体传输协议实现了端到端的视频流实时传输,并且采用AES加密算法针对实时视频流进行加密,保证了视频数据的安全性。文中全面展示了实时视频系统的搭建过程,并且通过Gstre-amer管道测试验证了该系统方案的可行性。测试结果表明,系统能够实时、准确、稳定、安全地将现场采集视频流信息显示到客户端,满足了远程视频监控系统的低时延、高安全的需求。

  13. [Assessment of learning activities using streaming video for laboratory practice education: aiming for development of E-learning system that promotes self-learning].

    Science.gov (United States)

    Takeda, Naohito; Takeuchi, Isao; Haruna, Mitsumasa

    2007-12-01

    In order to develop an e-learning system that promotes self-learning, lectures and basic operations in laboratory practice of chemistry were recorded and edited on DVD media, consisting of 8 streaming videos as learning materials. Twenty-six students wanted to watch the DVD, and answered the following questions after they had watched it: "Do you think the video would serve to encourage you to study independently in the laboratory practice?" Almost all students (95%) approved of its usefulness, and more than 60% of them watched the videos repeatedly in order to acquire deeper knowledge and skill of the experimental operations. More than 60% answered that the demonstration-experiment should be continued in the laboratory practice, in spite of distribution of the DVD media.

  14. MediaSite产品的教学流媒体视频系统%Making Teaching Streaming Media Video System Based on MediaSite

    Institute of Scientific and Technical Information of China (English)

    张翔

    2014-01-01

    Due to the school in the recording, the production, dissemination and the difficulties in the management of teachers’ classroom teaching video, this paper puts forward a set of teaching based on MediaSite streaming video production system. The article designs the MediaSite products based on teaching network platform of video streaming media system, proposes video tracking based on infrared technology and video technology of automatic focus. This system can largely simplify the teachers’ classroom teaching a lot of works on the video production and management. It is convenient for students studying in class. The system can promote the informatization level of the school, too.%鉴于学校在录制、制作、传播及管理教师课堂现场教学录像中的困难,本文提出了一套基于 MediaSite产品的教学流媒体视频制作系统,文章设计了基于 MediaSite 产品的教学流媒体视频系统的网络平台,提出基于红外技术的视频跟踪与摄像自动调焦技术。系统可很大程度上简化教师课堂现场教学录像制作与管理上的很多工作,方便学生在课下学习,可提升学校的信息化水平。

  15. MovieRemix: Having Fun Playing with Videos

    Directory of Open Access Journals (Sweden)

    Nicola Dusi

    2011-01-01

    scenario. Known as remix or video remix, the produced video may have new and different meanings with respect to the source material. Unfortunately, when managing audiovisual objects, the technological aspect can be a burden for many creative users. Motivated by the large success of the gaming market, we propose a novel game and an architecture to make the remix process a pleasant and stimulating gaming experience. MovieRemix allows people to act like a movie director, but instead of dealing with cast and cameras, the player has to create a remixed video starting from a given screenplay and from video shots retrieved from the provided catalog. MovieRemix is not a simple video editing tool nor is a simple game: it is a challenging environment that stimulates creativity. To temp to play the game, players can access different levels of screenplay (original, outline, derived and can also challenge other players. Computational and storage issues are kept at the server side, whereas the client device just needs to have the capability of playing streaming videos.

  16. Inferring Player Experiences Using Facial Expressions Analysis

    NARCIS (Netherlands)

    Tan, C.T.; Bakkes, S.; Pisan, Y.; Blackmore, K.; Nesbitt, K.; Smith, S.P.

    2014-01-01

    Understanding player experiences is central to game design. Video captures of players is a common practice for obtaining rich reviewable data for analysing these experiences. However, not enough has been done in investigating ways of preprocessing the video for a more efficient analysis process. Thi

  17. Video Self-Modeling

    Science.gov (United States)

    Buggey, Tom; Ogle, Lindsey

    2012-01-01

    Video self-modeling (VSM) first appeared on the psychology and education stage in the early 1970s. The practical applications of VSM were limited by lack of access to tools for editing video, which is necessary for almost all self-modeling videos. Thus, VSM remained in the research domain until the advent of camcorders and VCR/DVD players and,…

  18. Waisda?: video labeling game

    NARCIS (Netherlands)

    Hildebrand, M.; Brinkerink, M.; Gligorov, R.; Steenbergen, M. van; Huijkman, J.; Oomen, J.

    2013-01-01

    The Waisda? video labeling game is a crowsourcing tool to collect user-generated metadata for video clips. It follows the paradigm of games-with-a-purpose, where two or more users play against each other by entering tags that describe the content of the video. Players score points by entering the sa

  19. Android Video Streaming

    Science.gov (United States)

    2014-05-01

    2 2.2.1 HyperText Transfer Protocol (HTTP...simply copying a file in its entirety with no latency constraints). 2.2.1 HyperText Transfer Protocol (HTTP) As its name suggests, the HyperText ...Transfer Protocol (HTTP) was originally designed to transfer files containing formatted text written in the HyperText Markup Language (HTML) across a

  20. Influence of distortions of key frames on video transfer in wireless networks

    CERN Document Server

    Sagatov, E S; Calyam, P

    2010-01-01

    In this paper it is shown that for substantial increase of video quality in wireless network it is necessary to execute two obligatory points on modernization of the communication scheme. The player on the received part should throw back automatically duplicated RTP packets, server of streaming video should duplicate the packets containing the information of key frames. Coefficients of the mathematical model describing video quality in wireless network have been found for WiFi and 3G standards and codecs MPEG-2 and MPEG-4 (DivX). The special experimental technique which has allowed collecting and processing the data has been developed for calculation of values of factors.

  1. Immersive video

    Science.gov (United States)

    Moezzi, Saied; Katkere, Arun L.; Jain, Ramesh C.

    1996-03-01

    Interactive video and television viewers should have the power to control their viewing position. To make this a reality, we introduce the concept of Immersive Video, which employs computer vision and computer graphics technologies to provide remote users a sense of complete immersion when viewing an event. Immersive Video uses multiple videos of an event, captured from different perspectives, to generate a full 3D digital video of that event. That is accomplished by assimilating important information from each video stream into a comprehensive, dynamic, 3D model of the environment. Using this 3D digital video, interactive viewers can then move around the remote environment and observe the events taking place from any desired perspective. Our Immersive Video System currently provides interactive viewing and `walkthrus' of staged karate demonstrations, basketball games, dance performances, and typical campus scenes. In its full realization, Immersive Video will be a paradigm shift in visual communication which will revolutionize television and video media, and become an integral part of future telepresence and virtual reality systems.

  2. 用于Internet上视频流的一种改进的基于MDC的ORB-DCT方法%An Improved MDC-Based ORB-DCT Method for Video Streaming over the Internet

    Institute of Scientific and Technical Information of China (English)

    马然; 张兆扬; 江涛; 石旭利

    2005-01-01

    One of the most interesting questions of video streaming over the Intemet is packet loss. Some error resilient technologies havebeen proposed to overcome quality decrease of reconstructed video occurred due to packet loss, in which optimized reconstructionbased DCT (ORB-DCT) utilizes two-direction interleaving. An improved ORB-DCT (IORB-DCT), which uses four-direction interleaving, is proposed in this paper. Experimental results are demonstrated to verify the effectiveness of the proposed IORB-DCT.

  3. 多组视频流的实时图象拼接%Real-Time Image Mosaicing for Multiple Live Video Streams

    Institute of Scientific and Technical Information of China (English)

    N.R. Wanigasekara; 曾勇勤; 严壮志

    2003-01-01

    此文介绍了一个实时图象拼接系统.该系统从多个录像设备(如网络摄像头)采集的视频流中实时拼接出全景图象.本系统由两个主要摸块组成:实时视频采集,实时图象拼接以及自动更新.为有效地实现图象匹配,该系统运用了基于多分辨率特征的方法.此算法较之传统的基于亮度的方法有着更多优点.实验结果显示上述系统实现了高质量图象拼接并明显地提高了实时处理的速度.本系统适合于如视频监控以及虚拟现实等应用.%This paper describes a real-time image mosaicing system that creates panoramas from multiple video streams captured by video devices such as webcams. The implemented system consists of two principal modules:live video capturing and real time image mosaicing with automatic updating. It uses a multi-resolution feature based method for effective image registration, which has many advantages over traditional intensity based approaches.Experimental results demonstrate the superior validity of the proposed system by providing high quality real time image mosaics with significant speedup in computation. The proposed system is suitable for applications such as video surveillance and virtual reality, etc.

  4. Understanding Video Games

    DEFF Research Database (Denmark)

    Heide Smith, Jonas; Tosca, Susana Pajares; Egenfeldt-Nielsen, Simon

    From Pong to PlayStation 3 and beyond, Understanding Video Games is the first general introduction to the exciting new field of video game studies. This textbook traces the history of video games, introduces the major theories used to analyze games such as ludology and narratology, reviews...... the economics of the game industry, examines the aesthetics of game design, surveys the broad range of game genres, explores player culture, and addresses the major debates surrounding the medium, from educational benefits to the effects of violence. Throughout the book, the authors ask readers to consider...... larger questions about the medium: * What defines a video game? * Who plays games? * Why do we play games? * How do games affect the player? Extensively illustrated, Understanding Video Games is an indispensable and comprehensive resource for those interested in the ways video games are reshaping...

  5. Jump frequency may contribute to risk of jumper's knee: a study of interindividual and sex differences in a total of 11,943 jumps video recorded during training and matches in young elite volleyball players.

    Science.gov (United States)

    Bahr, Martin A; Bahr, Roald

    2014-09-01

    Male sex, total training volume (number of hours per week) and match exposure (number of sets played per week) are risk factors for jumper's knee among young elite volleyball players. However, it is not known whether jump frequency differs among players on the same squad. To examine interindividual and sex differences in jump frequency during training and matches in young elite volleyball players. Observational study. Norwegian elite volleyball boarding school training programme. Student-athletes (26 boys and 18 girls, 16-18 years). Individual jump counts were recorded based on visual analysis of video recordings obtained from 1 week of volleyball training (9 training sessions for boys and 10 for girls, 14.1 h and 17.8 h of training, respectively) and 10 matches (5.9 h for boys (16 sets) and 7.7 h for girls (21 sets). A total of 11,943 jumps were recorded, 4138 during matches and 7805 during training. As training attendance and jump frequency varied substantially between players, the total exposure in training ranged from 50 to 666 jumps/week among boys and from 11 to 251 jumps/week among girls. On average, this corresponded to 35.7 jumps/h for boys and 13.7 jumps/h for girls (Student t test, p=0.002). Total jump exposure during matches ranged between 1 and 339 jumps among boys and between 0 and 379 jumps among girls, corresponding to an average jump frequency of 62.2 jumps/h for boys and 41.9 jumps/h for girls (Student t test, pvolleyball players. Total jump volume may represent a more important risk factor for jumper's knee than total training volume, warranting further research attention. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  6. Video Games and Digital Literacies

    Science.gov (United States)

    Steinkuehler, Constance

    2010-01-01

    Today's youth are situated in a complex information ecology that includes video games and print texts. At the basic level, video game play itself is a form of digital literacy practice. If we widen our focus from the "individual player + technology" to the online communities that play them, we find that video games also lie at the nexus of a…

  7. Video Games and Digital Literacies

    Science.gov (United States)

    Steinkuehler, Constance

    2010-01-01

    Today's youth are situated in a complex information ecology that includes video games and print texts. At the basic level, video game play itself is a form of digital literacy practice. If we widen our focus from the "individual player + technology" to the online communities that play them, we find that video games also lie at the nexus of a…

  8. Design and Implementation of Peking University Video Resource Library Based on Flash Streaming Media Server%基于Flash流媒体服务器的北大视频资源库的设计与实现

    Institute of Scientific and Technical Information of China (English)

    杨公义

    2016-01-01

    Video resource library made by independent research and development integrates more easily to the third party system in school. Flash streaming media server has been used to develop the video resource library in Peking University. The function modules include: user management, department management, curriculum management, video management. The live stream of the video camera can be stored in this library. The teaching video after the nonlinear editing can be uploaded to this library in browser through large file upload component which are independent research and development. Streaming permission control ensures that the camera can't send the video stream to the library until it passes through the authorization. Only the authorized third party system can reference the video resources of the streaming media server. For the school's seven major systems this library provides RTMP protocol video stream support, metadata management and content distribution.%自主研发视频资源库更易于和校内第三方系统集成。北大采用Flash流媒体服务器研发了视频资源库,功能模块包括用户管理,院系管理,课程管理,视频管理。摄像机的直播流能通过分布式转码自动存入北大视频资源库。后期经过非线性编辑的教学录像能通过自主研发的大文件上传控件从前台以 web 方式存入北大视频资源库。通过流权限控制保证了只有经过授权的摄像机才能向服务器端发送视频流,只有经过授权的第三方系统才能引用流媒体服务器的视频资源。北大视频资源库为校内七大系统提供RTMP协议的视频流支持、元数据管理和内容发布。

  9. StreamWorks: the live and on-demand audio/video server and its applications in medical information systems

    Science.gov (United States)

    Akrout, Nabil M.; Gordon, Howard; Palisson, Patrice M.; Prost, Remy; Goutte, Robert

    1996-05-01

    Facing a world undergoing fundamental and rapid change, healthcare organizations are seeking ways to increase innovation, quality, productivity, and patient value, keys to more effective care. Individual clinics acting alone can respond in only a limited way, so re- engineering the process key which services are delivered demands real-time collaborative technology that provides immediate information sharing, improving the management and coordination of information in cross-functional teams. StreamWorks is a development stage architecture that uses a distribution technique to deliver an advanced information management system for telemedicine. The challenge of StreamWorks in telemedicine is to enable equity of the quality of Health Care of Telecommunications and Information Technology also to patients in less favored regions, like India or China, where the quality of medical care varies greatly by region, but where there are some very current communications facilities.

  10. Publicación de materiales audiovisuales a través de un servidor de video-streaming Publication of audio-visual materials through a streaming video server

    OpenAIRE

    Acevedo Clavijo Edwin Jovanny; Parra Toloza Dina Julieth; Winlker Hernadez Walter

    2010-01-01

    Esta propuesta tiene como objetivo estudiar varias alternativas de servidores Streaming para determinar la mejor herramienta para el desarrollo de la publicación de material audiovisual educativo. Se evaluaron las plataformas más utilizadas teniendo en cuenta sus características y beneficios que tiene cada servidor entre las los cuales están: Hélix Universal Server, Windows Media Server de Microsoft, Peer Cast y Darwin Server. implementando un servidor con mayores capacidades y beneficios par...

  11. 基于DONet模型的视频直播系统%A live video streaming system based on DONet

    Institute of Scientific and Technical Information of China (English)

    吕燕乐; 文登敏; 丁宵琪

    2008-01-01

    分析现有P2P流媒体系统存在的问题,以及研究DONet系统控制和数据传输两方面主要技术的基础上,设计并实现了一个基于DONet模型的P2P流媒体在线直播系统PP-video.该系统通过在局域网中的运行测试,表明PP-Video有较高的稳定性,并且有很好的吞吐量.

  12. Inferring playback rate and rate resets of P2P video streaming transmissions by piecewise line envelope approximation

    Institute of Scientific and Technical Information of China (English)

    LI Chun-xi; CHEN Chang-jia

    2009-01-01

    Conventionally, P2P video is regarded as CBR traffic. However, our measurements have shown that the rate reset cannot be neglected in a practical IPTV system because each rate reset often leads to performance degradation. Thus, addressing the problem of inferring playback rate and rate reset in a P2P video system is significant. In this article, an algorithm termed piecewise linear envelope approximation (PLEA) is proposed, in which a follow-up time is introduced to smooth rate fluctuations in a small time scale and to adapt rate jumps in a large time scale automatically. With the PLEA algorithm, discontinuity introduced by blind segmentations adopted by current methods is avoided. Furthermore, unlike existing algorithms in which both segmentation and combinations are performed in multiple runs, only a single computation path is involved in the PLEA algorithm. This makes PLEA algorithm amenable to implementation of low complexity by either software or hardware. Both theoretical analysis and experiment based on measured data show that the PLEA outperforms existing algorithms based on segmentation.

  13. Veto players

    NARCIS (Netherlands)

    Warntjen, Andreas; Dowding, Keith

    2010-01-01

    Veto players are political actors whose consent is necessary to adopt a new policy. Put otherwise, they have veto power which allows them to prevent a change to the status quo. The concept is crucial to the influential veto player theory developed by George Tsebelis. Building on earlier work in form

  14. Veto players

    NARCIS (Netherlands)

    Warntjen, Andreas; Dowding, Keith

    2010-01-01

    Veto players are political actors whose consent is necessary to adopt a new policy. Put otherwise, they have veto power which allows them to prevent a change to the status quo. The concept is crucial to the influential veto player theory developed by George Tsebelis. Building on earlier work in form

  15. Las posibilidades didácticas y manejo de Video Streaming en las clases de lengua y literatura.

    Directory of Open Access Journals (Sweden)

    José Soto Vázquez

    2009-01-01

    Full Text Available Resumen: La incorporación de las nuevas tecnologías en las aulas ha supuesto una nueva concepción del modelo educativo en el que el docente juega un papel determinante. No obstante, la diversidad de herramientas didácticas es tan amplia que necesita de trabajos parciales que enfoquen la utilidad de cada una de ellas. En este sentido, la enseñanza de las lenguas tiene en V Streaming una pieza fundamental que permite estudiar la lengua oral actual, a la vez que alienta el uso de las nuevas tecnologías.Summary: The incorporation of new technologies into the classroom has meant a new conception of the educational model where the teacher plays an important role. Nevertheless, the diversity of didactic tools is so wide that partial works are required to focus the utility of each of them. In this respect, the teaching of languages have in V Streaming a fundamental piece that allows studying current oral language, as well as encouraging the use of new technologies.

  16. An investigation of player to player character identification via personal pronouns

    DEFF Research Database (Denmark)

    Hichens, Michael; Drachen, Anders; Richards, Deborah

    2012-01-01

    The player character is an important feature of many games, where it is through the character that the player interacts with game world. There has been considerable interest in the relationship between the player and the player character. Much of this work has examined the identification of players...... in playing video games, did have a statistically significant affect, indicating that different levels of identification are more dependent on the player than on the game. This indicates that players are not a homogeneous group with respect to player character identification and is an important consideration...... with their characters, generally taking either a textual analysis approach, or has been empirical work that has explicitly identified the idea of identification through survey instruments, etc. The work presented here takes a different empirical approach, focusing on the use of various pronoun forms (first, second...

  17. ASI/SDI transport stream player based on FPGA design and implementation%基于FPGA的ASI/SDI码流播放器的设计与实现

    Institute of Scientific and Technical Information of China (English)

    许盛世; 方志强; 俞东雷

    2013-01-01

    随着数字技术的发展,数字产品的普及,各种数字电视工作人员专用测试工具不断被开发.针对码流播放器的市场需要的目的,采用基于FPGA的系统架构的方法,结合硬件及软件设计等方面内容,文中详细介绍了一个包含码流录制、码流播放、码流分析等多种功能的ASI/SDI码流播放器的设计与实现的过程.%With the development of digital technology,the popularity of digital products,all kinds of digital TV staff special test tools for continuous was developed.For the market need of TS-Player,with the method based on FPGA system structure,this paper introduces the process of ASI/SDI code flow player design and implementation in detail from hardware and software design,etc.,which contains code flow recording,code flow play,code flow analysis and so on the many kinds of functions.

  18. File format for storage of scalable video

    Institute of Scientific and Technical Information of China (English)

    BAI Gang; SUN Xiao-yan; WU Feng; YIN Bao-cai; LI Shi-peng

    2006-01-01

    A file format for storage of scalable video is proposed in this paper. A generic model is presented to enable a codec independent description of scalable video stream. The relationships, especially the dependencies, among sub-streams in a scalable video stream are specified sufficiently and effectively in the proposed model. Complying with the presented scalable video stream model, the file format for scalable video is proposed based on ISO Base Media File Format, which is simple and flexible enough to address the demands of scalable video application as well as the non-scalable ones.

  19. A new video programme

    CERN Multimedia

    CERN video productions

    2011-01-01

    "What's new @ CERN?", a new monthly video programme, will be broadcast on the Monday of every month on webcast.cern.ch. Aimed at the general public, the programme will cover the latest CERN news, with guests and explanatory features. Tune in on Monday 3 October at 4 pm (CET) to see the programme in English, and then at 4:20 pm (CET) for the French version.   var flash_video_player=get_video_player_path(); insert_player_for_external('Video/Public/Movies/2011/CERN-MOVIE-2011-129/CERN-MOVIE-2011-129-0753-kbps-640x360-25-fps-audio-64-kbps-44-kHz-stereo', 'mms://mediastream.cern.ch/MediaArchive/Video/Public/Movies/2011/CERN-MOVIE-2011-129/CERN-MOVIE-2011-129-Multirate-200-to-753-kbps-640x360-25-fps.wmv', 'false', 480, 360, 'https://mediastream.cern.ch/MediaArchive/Video/Public/Movies/2011/CERN-MOVIE-2011-129/CERN-MOVIE-2011-129-posterframe-640x360-at-10-percent.jpg', '1383406', true, 'Video/Public/Movies/2011/CERN-MOVIE-2011-129/CERN-MOVIE-2011-129-0600-kbps-maxH-360-25-fps-...

  20. 新型双重混合的流媒体直播系统架构%Novel Double Hybrid Architecture of Live Video Streaming System

    Institute of Scientific and Technical Information of China (English)

    黄思嘉; 吕智慧; 吴杰

    2011-01-01

    Based on Content Delivery Network(CDN) and Peer-to-Peer network(P2P), this paper designs a new double hybrid architecture of live video streaming system. based on research of hybrid CDN-P2P network, which are hybrid CDN-P2P, and hybrid Tree-Mesh. Mainly Elaborate the system architecture, construct of CoreTree and peer selection algorithm. And through the system simulation, result shows that this system has low delay of playing and starting than other popular architectures.%研究内容分发网络(CDN)与对等网络(P2P)的混合模型,提出一种CDN与P2P、树形结构与网状结构双重混合的流媒体直播系统架构.设计基于CDN-P2P的树网结合直播系统模型,阐述核心树的主要构建机制,介绍网状结构的节点选择算法.系统仿真结果表明,与纯P2P模型及CDN-P2P混合模型相比,该系统的播放和启动延迟较小.

  1. A Gaussian mixture clustering model for characterizing football players using the EA Sports' FIFA video game system. [Modelo basado en agrupamiento de mixturas Gaussianas para caracterizar futbolistas utilizando el sistema de videojuegos FIFA de EA Sports].

    Directory of Open Access Journals (Sweden)

    César Soto-Valero

    2017-07-01

    Full Text Available The generation and availability of football data has increased considerably last decades, mostly due to its popularity and also because of technological advances. Gaussian mixture clustering models represents a novel approach to exploring and analyzing performance data in sports. In this paper, we use principal components analysis in conjunction with a model-based Gaussian clustering method with the purpose of characterizing professional football players. Our model approach is tested using 40 attributes from EA Sports' FIFA video game series system, corresponding to 7705 European players. Clustering results reveal a clear distinction among different performance indicators, representing four different roles in the team. Players were labeled according to these roles and a gradient tree boosting model was used for ranking attributes regarding to its importance. We found that the dribbling skill is the most discriminating variable among the different clustered players’ profiles. Resumen En las últimas décadas se ha visto un incremento considerable en la generación y disponibilidad de datos de fútbol, esto se debe fundamentalmente a la popularidad de este deporte así como a los avances tecnológicos realizados en este campo. Los modelos de agrupamiento basados en mixturas Gaussianas representan un enfoque novedoso para explorar y analizar datos de desempeño deportivo. En el presente trabajo, se lleva a cabo una caracterización de jugadores profesionales de fútbol utilizando técnicas de análisis de componentes principales y agrupamiento basados en mixturas Gaussianas. El modelo presentado es comprobado utilizando datos del sistema de videojuegos FIFA de EA Sports, dichos datos representan 40 atributos correspondientes a 7705 futbolistas europeos. Los resultados del agrupamiento revelan una clara distinción entre algunos indicadores de desempeño, los cuales corresponden a cuatro roles diferentes en el equipo. Consecuentemente, los

  2. 基于流媒体技术的体育竞赛视频发布系统设计%Design of Sports Competition Video Release System Based on Streaming Media Technology

    Institute of Scientific and Technical Information of China (English)

    缪刚; 王萍; 庄亚军; 夏伟

    2016-01-01

    根据体育竞赛信息发布系统逐步趋向移动化、可视化的发展趋势,提出了基于流媒体技术的体育竞赛视频发布系统设计。突破传统思维,利用高清网络摄像机,将体育竞赛的视频信息发布从单一的电视转播发布,扩展到全方位覆盖的网络视频信息发布。将采集到的视频流发送至基于Linux 内核的 Nginx 流媒体服务器,服务器对视频进行转码,并根据 HLS 协议对视频进行切片处理。最终将视频分别发布到 PC 端及移动端,实现了整个系统的跨平台运行。设计已成功应用于2015年第一届全国青年运动会,运行结果稳定,视频发布流畅,满足了综合型运动会的信息发布需求。%As the sports competition information release system trending to development of the mobility and visualization,the design of sports competition video publishing system,out of the traditional thinking,based on streaming media technology,is proposed.The video game can be released from a single video broadcast signals to a full range of coverage of the network video information by means of the high -definition network camera.The video streaming will be sent to the streaming media server based on Nginx.By transcoding video and HLS slices,the video will be released to the mobile terminal and PC terminal to run the system cross platform.The design has been successfully used in the first National Youth Games in 2015.The test result shows that the operation is stable,the video released is smooth and the design meets the needs of information release for the integrated sports meeting.

  3. Intelligent video surveillance systems

    CERN Document Server

    Dufour, Jean-Yves

    2012-01-01

    Belonging to the wider academic field of computer vision, video analytics has aroused a phenomenal surge of interest since the current millennium. Video analytics is intended to solve the problem of the incapability of exploiting video streams in real time for the purpose of detection or anticipation. It involves analyzing the videos using algorithms that detect and track objects of interest over time and that indicate the presence of events or suspect behavior involving these objects.The aims of this book are to highlight the operational attempts of video analytics, to identify possi

  4. The Design and Implementation of Smartphone Based Mobile Live Video Streaming System%一种基于Android手机的移动视频直播系统的设计与实现

    Institute of Scientific and Technical Information of China (English)

    杨名阳; 张志刚; 叶保留

    2013-01-01

    The Advances in wireless communication and mobile computing techniques provide new venues to support novel live streaming systems. However, the dynamics of network as well as the realtime requirement of streaming service impose additional challenges on the implementation. In this paper, we design and implement a mobile live video streaming system over Android based smartphones. The implemented system enables users to capture the on-spot video with the video camera embedded in smartphone and upload to the media server via either WiFi or 3G networks, providing live and/or on-demand streaming services to remote users. We describe the design and implementation mechanism of the key components involved in the system, including video capturing/encoding, video processing/publishing and video playback. In addition, we also evaluate and compare the encoding and transmission performance of the system over different scenarios.%无线网络及移动计算技术的发展为面向新型网络环境的在线视频直播提供了机遇,但网络的动态性及流服务的实时性也对系统实现带来挑战.针对上述问题,本文设计并实现了一个基于Android手机的移动视频直播系统,该系统支.持用户通过智能手机内嵌摄像头实时采集现场视频信息,并通过Wi-Fi或3G等上传视频流至服务器,提供在线直播或点播服务.文中详细描述了视频采集、视频发布处理和视频播放等核心功能的设计与实现机制,并从视频编码和网络传输两个方面对系统性能进行了分析.

  5. Digital video technology, today and tomorrow

    Science.gov (United States)

    Liberman, J.

    1994-10-01

    Digital video is probably computing's fastest moving technology today. Just three years ago, the zenith of digital video technology on the PC was the successful marriage of digital text and graphics with analog audio and video by means of expensive analog laser disc players and video overlay boards. The state of the art involves two different approaches to fully digital video on computers: hardware-assisted and software-only solutions.

  6. A Game-based Corpus for Analysing the Interplay between Game Context and Player Experience

    DEFF Research Database (Denmark)

    Shaker, Noor; Yannakakis, Georgios N.; Asteriadis, Stylianos;

    2011-01-01

    Recognizing players' aective state while playing video games has been the focus of many recent research studies. In this paper we describe the process that has been followed to build a corpus based on game events and recorded video sessions from human players while playing Super Mario Bros. We...... present dierent types of information that have been extracted from game context, player preferences and perception of the game, as well as user features, automatically extracted from video recordings.We run a number of initial experiments to analyse players' behavior while playing video games as a case...

  7. Categorizing Video Game Audio

    DEFF Research Database (Denmark)

    Westerberg, Andreas Rytter; Schoenau-Fog, Henrik

    2015-01-01

    This paper dives into the subject of video game audio and how it can be categorized in order to deliver a message to a player in the most precise way. A new categorization, with a new take on the diegetic spaces, can be used a tool of inspiration for sound- and game-designers to rethink how they ...

  8. Interactive video algorithms and technologies

    CERN Document Server

    Hammoud, Riad

    2006-01-01

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

  9. Video game use and cognitive performance: does it vary with the presence of problematic video game use?

    Science.gov (United States)

    Collins, Emily; Freeman, Jonathan

    2014-03-01

    Action video game players have been found to outperform nonplayers on a variety of cognitive tasks. However, several failures to replicate these video game player advantages have indicated that this relationship may not be straightforward. Moreover, despite the discovery that problematic video game players do not appear to demonstrate the same superior performance as nonproblematic video game players in relation to multiple object tracking paradigms, this has not been investigated for other tasks. Consequently, this study compared gamers and nongamers in task switching ability, visual short-term memory, mental rotation, enumeration, and flanker interference, as well as investigated the influence of self-reported problematic video game use. A total of 66 participants completed the experiment, 26 of whom played action video games, including 20 problematic players. The results revealed no significant effect of playing action video games, nor any influence of problematic video game play. This indicates that the previously reported cognitive advantages in video game players may be restricted to specific task features or samples. Furthermore, problematic video game play may not have a detrimental effect on cognitive performance, although this is difficult to ascertain considering the lack of video game player advantage. More research is therefore sorely needed.

  10. Developing a Video Steganography Toolkit

    OpenAIRE

    Ridgway, James; Stannett, Mike

    2014-01-01

    Although techniques for separate image and audio steganography are widely known, relatively little has been described concerning the hiding of information within video streams ("video steganography"). In this paper we review the current state of the art in this field, and describe the key issues we have encountered in developing a practical video steganography system. A supporting video is also available online at http://www.youtube.com/watch?v=YhnlHmZolRM

  11. Using MPEG DASH SRD for zoomable and navigable video

    NARCIS (Netherlands)

    D'Acunto, L.; Berg, J. van den; Thomas, E.; Niamut, O.A.

    2016-01-01

    This paper presents a video streaming client implementation that makes use of the Spatial Relationship Description (SRD) feature of the MPEG-DASH standard, to provide a zoomable and navigable video to an end user. SRD allows a video streaming client to request spatial subparts of a particular video

  12. Using MPEG DASH SRD for zoomable and navigable video

    NARCIS (Netherlands)

    D'Acunto, L.; Berg, J. van den; Thomas, E.; Niamut, O.A.

    2016-01-01

    This paper presents a video streaming client implementation that makes use of the Spatial Relationship Description (SRD) feature of the MPEG-DASH standard, to provide a zoomable and navigable video to an end user. SRD allows a video streaming client to request spatial subparts of a particular video

  13. Creating interactive video broadcasting system for VBLHEP

    Science.gov (United States)

    Slepov, I. P.

    2016-09-01

    The article describes the creation of a web service, which combines the possibility of organizing video broadcasts and video conferences for the VBLHEP, JINR events. Software and hardware components used for the organization of video streaming and video conferencing are presented.

  14. Persistent Temporal Streams

    Science.gov (United States)

    Hilley, David; Ramachandran, Umakishore

    Distributed continuous live stream analysis applications are increasingly common. Video-based surveillance, emergency response, disaster recovery, and critical infrastructure protection are all examples of such applications. They are characterized by a variety of high- and low-bandwidth streams as well as a need for analyzing both live and archived streams. We present a system called Persistent Temporal Streams (PTS) that supports a higher-level, domain-targeted programming abstraction for such applications. PTS provides a simple but expressive stream abstraction encompassing transport, manipulation and storage of streaming data. In this paper, we present a system architecture for implementing PTS. We provide an experimental evaluation which shows the system-level primitives can be implemented in a lightweight and high-performance manner, and an application-based evaluation designed to show that a representative high-bandwidth stream analysis application can be implemented relatively simply and with good performance.

  15. "School Shooter" Web Video Game Raises Concerns

    Science.gov (United States)

    Rhen, Brad

    2011-01-01

    A new video game in which the player stalks and shoots fellow students and teachers in school settings is drawing fire from school district officials. "School Shooter: North American Tour 2012" is a first-person game that allows the player to move around a school and collect points by killing defenseless students and teachers. The game,…

  16. A P2P Platform for Real-Time Multicast Video Streaming Leveraging on Scalable Multiple Descriptions to Cope with Bandwidth Fluctuations

    National Research Council Canada - National Science Library

    Lorenzo Favalli; Marco Folli; Alfio Lombardo; Diego Reforgiato; Giovanni Schembra

    2011-01-01

    ... and performance.The target of this paper is to propose a content delivery system for real-time streaming services based ona peer-to-peer approach that exploits multicast overlay organization of the peers to address...

  17. A randomized controlled trial of soap opera videos streamed to smartphones to reduce risk of sexually transmitted human immunodeficiency virus (HIV) in young urban African American women.

    Science.gov (United States)

    Jones, Rachel; Hoover, Donald R; Lacroix, Lorraine J

    2013-01-01

    Love, Sex, and Choices (LSC) is a soap opera video series created to reduce HIV sex risk in women. LSC was compared to text messages in a randomized trial in 238 high-risk mostly Black young urban women. 117 received 12-weekly LSC videos, 121 received 12-weekly HIV prevention messages on smartphones. Changes in unprotected sex with high risk partners were compared by mixed models. Unprotected sex with high risk men significantly declined over 6 months post-intervention for both arms, from 21-22 acts to 5-6 (p soap opera video episodes to reduce HIV risk on smartphones. LSC holds promise as an Internet intervention that could be scaled-up and combined with HIV testing. Copyright © 2013 Elsevier Inc. All rights reserved.

  18. ATLAS Live: Collaborative Information Streams

    CERN Document Server

    Goldfarb, S; The ATLAS collaboration

    2011-01-01

    I report on a pilot project launched in 2010 focusing on facilitating communication and information exchange within the ATLAS Collaboration, through the combination of digital signage software and webcasting. The project, called ATLAS Live, implements video streams of information, ranging from detailed detector and data status to educational and outreach material. The content, including text, images, video and audio, is collected, visualised and scheduled using digital signage software. The system is robust and flexible, utilizing scripts to input data from remote sources, such as the CERN Document Server, Indico, or any available URL, and to integrate these sources into professional-quality streams, including text scrolling, transition effects, inter and intra-screen divisibility. Information is published via the encoding and webcasting of standard video streams, viewable on all common platforms, using a web browser or other common video tool. Authorisation is enforced at the level of the streaming and at th...

  19. ATLAS Live: Collaborative Information Streams

    Science.gov (United States)

    Goldfarb, Steven; ATLAS Collaboration

    2011-12-01

    I report on a pilot project launched in 2010 focusing on facilitating communication and information exchange within the ATLAS Collaboration, through the combination of digital signage software and webcasting. The project, called ATLAS Live, implements video streams of information, ranging from detailed detector and data status to educational and outreach material. The content, including text, images, video and audio, is collected, visualised and scheduled using digital signage software. The system is robust and flexible, utilizing scripts to input data from remote sources, such as the CERN Document Server, Indico, or any available URL, and to integrate these sources into professional-quality streams, including text scrolling, transition effects, inter and intra-screen divisibility. Information is published via the encoding and webcasting of standard video streams, viewable on all common platforms, using a web browser or other common video tool. Authorisation is enforced at the level of the streaming and at the web portals, using the CERN SSO system.

  20. ATLAS Live: Collaborative Information Streams

    CERN Document Server

    Goldfarb, S; The ATLAS collaboration

    2010-01-01

    I report on a pilot project launched in 2010 focusing on facilitating communication and information exchange within the ATLAS Collaboration, through the combination of digital signage software and webcasting. The project, called ATLAS Live, implements video streams of information, ranging from detailed detector and data status to educational and outreach material. The content, including text, images, video and audio, is collected, visualised and scheduled using the SCALA digital signage software system. The system is robust and flexible, allowing for the usage of scripts to input data from remote sources, such as the CERN Document Server, Indico, or any available URL, and to integrate these sources into professional-quality streams, including text scrolling, transition effects, inter and intrascreen divisibility. The video is made available to the collaboration or public through the encoding and webcasting of standard video streams, viewable on all common platforms, using a web browser or other common video t...

  1. Fragile watermarking algorithm for the integrity authentication of video bit-stream of H.264/AVC%H.264/AVC视频流完整性认证的脆弱水印算法

    Institute of Scientific and Technical Information of China (English)

    王让定; 朱洪留; 徐达文

    2011-01-01

    提出一种基于脆弱水印的视频流完整性认证方法,在H.264压缩比特流中,首先根据I_Slice中4×4块的编码模式生成认证码,然后通过调制某些运动子块的VLC码字将其嵌入B_Slice和P_Slice的视频流中.这种调制是基于VLC码字和待嵌入比特之间的映射规则进行的.映射后的码字与原码字具有很好的相似性,即码字长度不变,码字表示的编码元素值相似.该算法可以实现水印的快速提取,满足视频实时处理的要求.实验仿真结果表明,本算法具有较小的视频失真,并能有效地对视频帧进行完整性认证.%An integrity authentication scheme for video bit-stream based on the fragile watermarking is proposed in this paper.In the compressed bit-stream of H.264, The authentication cedeword are generated according to the mode of intra_4 × 4 in I_Slice firstly, and then embedded into B_Slice and P_Slice by modulating some VLC codeword of sub-block.This modulation is based on the mapping rule between the VLC cedeword and the bit to be embedded.The mapped codeword is very similar to the original codeword, namely, the length of cedeword is same and the value of coding element is similar.This scheme could detect the watermarking rapidly, which meets the requirement of the real-time processing of video.Experimental results show that it has less influence on the quality of video, and can effectively carry out the integral certification of video frame.

  2. Improving Peer-to-Peer Video Systems

    NARCIS (Netherlands)

    Petrocco, R.P.

    2016-01-01

    Video Streaming is nowadays the Internet’s biggest source of consumer traffic. Traditional content providers rely on centralised client-server model for distributing their video streaming content. The current generation is moving from being passive viewers, or content consumers, to active content pr

  3. Improving Peer-to-Peer Video Systems

    NARCIS (Netherlands)

    Petrocco, R.P.

    2016-01-01

    Video Streaming is nowadays the Internet’s biggest source of consumer traffic. Traditional content providers rely on centralised client-server model for distributing their video streaming content. The current generation is moving from being passive viewers, or content consumers, to active content pr

  4. Improving Peer-to-Peer Video Systems

    NARCIS (Netherlands)

    Petrocco, R.P.

    2016-01-01

    Video Streaming is nowadays the Internet’s biggest source of consumer traffic. Traditional content providers rely on centralised client-server model for distributing their video streaming content. The current generation is moving from being passive viewers, or content consumers, to active content

  5. 3G流媒体系统性能评估与仿真平台%A PERFORMANCE EVALUATION AND SIMULATION PLATFORM FOR VIDEO STREAMING SYSTEMS BASED ON 3G NETWORKS

    Institute of Scientific and Technical Information of China (English)

    刘思贤; 刘新; 叶德建; 肖晴

    2013-01-01

    With increasing improvement of 3G network construction, video streaming services will become one of the main value-added services. However, to individually evaluate the performance of new applications and network standards makes the work repetitive and increases the cost as well. To solve the problem, a performance evaluation and simulation platform for 3G-based video streaming systems is proposed in this paper. The system is highly flexible, users can evaluate the impact of distribution policy and networks status on the quality of service with less cost by modifying the configuration. Moreover, a simulation example for reference based on CDMA 2000 1xEV-DO Rev. A network is implemented upon the platform. The system is meaningful for proper technologies selection and services development of business operation support platforms.%随着3G网络建设的日益完善,流媒体业务将逐渐成为主流的增值业务之一.然而,为新的应用和网络标准进行单独的性能评估工作重复且增加成本.针对此问题,提出一个面向3G网络的流媒体性能评估与仿真平台.该系统具有高度的灵活性,用户可以通过调整配置,以较小的代价评估分发策略和网络状况对服务质量的影响.在系统之上,还给出了一套基于CDMA 20001xEV-DO Rev.A网络的参考仿真实现.该系统对于业务运营支撑平台的技术选型及业务发展具有一定的参考意义.

  6. Sex, Lies and Video Games

    Science.gov (United States)

    Kearney, Paul; Pivec, Maja

    2007-01-01

    Sex and violence in video games is a social issue that confronts us all, especially as many commercial games are now being introduced for game-based learning in schools, and as such this paper polls teenage players about the rules their parents and teachers may or may not have, and surveys the gaming community, ie, game developers to parents, to…

  7. Sex, Lies and Video Games

    Science.gov (United States)

    Kearney, Paul; Pivec, Maja

    2007-01-01

    Sex and violence in video games is a social issue that confronts us all, especially as many commercial games are now being introduced for game-based learning in schools, and as such this paper polls teenage players about the rules their parents and teachers may or may not have, and surveys the gaming community, ie, game developers to parents, to…

  8. Technology consumption and cognitive control: Contrasting action video game experience with media multitasking.

    Science.gov (United States)

    Cardoso-Leite, Pedro; Kludt, Rachel; Vignola, Gianluca; Ma, Wei Ji; Green, C Shawn; Bavelier, Daphne

    2016-01-01

    Technology has the potential to impact cognition in many ways. Here we contrast two forms of technology usage: (1) media multitasking (i.e., the simultaneous consumption of multiple streams of media, such a texting while watching TV) and (2) playing action video games (a particular subtype of video games). Previous work has outlined an association between high levels of media multitasking and specific deficits in handling distracting information, whereas playing action video games has been associated with enhanced attentional control. Because these two factors are linked with reasonably opposing effects, failing to take them jointly into account may result in inappropriate conclusions as to the impacts of technology use on attention. Across four tasks (AX-continuous performance, N-back, task-switching, and filter tasks), testing different aspects of attention and cognition, we showed that heavy media multitaskers perform worse than light media multitaskers. Contrary to previous reports, though, the performance deficit was not specifically tied to distractors, but was instead more global in nature. Interestingly, participants with intermediate levels of media multitasking sometimes performed better than both light and heavy media multitaskers, suggesting that the effects of increasing media multitasking are not monotonic. Action video game players, as expected, outperformed non-video-game players on all tasks. However, surprisingly, this was true only for participants with intermediate levels of media multitasking, suggesting that playing action video games does not protect against the deleterious effect of heavy media multitasking. Taken together, these findings show that media consumption can have complex and counterintuitive effects on attentional control.

  9. Technology consumption and cognitive control: Contrasting action video game experience with media multitasking

    Science.gov (United States)

    Cardoso-Leite, Pedro; Kludt, Rachel; Vignola, Gianluca; Ma, Wei Ji; Green, C. Shawn; Bavelier, Daphne

    2015-01-01

    Technology has the potential to impact cognition in many ways. Here we contrast two forms of technology usage: 1) media multitasking (i.e., the simultaneous consumption of multiple streams of media, such a texting while watching TV) and 2) playing action video games (a particular sub-type of video game). Previous work has outlined an association between high levels of media multitasking and specific deficits in handling distracting information, while playing action video games has been associated with enhanced attentional control. As these two factors are linked with reasonably opposing effects, failing to take them jointly into account may result in inappropriate conclusions as to the impact of technology use on attention. Across four experiments (AX-CPT, N-back, Task-switching and Filter task), testing different aspects of attention and cognition, we show that heavy media multitaskers perform worse than light media multitaskers. Contrary to previous reports though, the performance deficit was not specifically tied to distractors, but was instead more global in nature. Interestingly, participants with intermediate levels of media multitasking occasionally performed better than both light and heavy media multitaskers suggesting that the effects of increasing media multitasking are not monotonic. Action video game players, as expected, outperformed non-video game players on all tasks. However, surprisingly this was true only for participants with intermediate levels of media multitasking, suggesting that playing action video games does not protect against the deleterious effect of heavy media multitasking. Taken together this study shows that media consumption can have complex and counter-intuitive effects on attentional control. PMID:26474982

  10. Video game narrative and criticism playing the story

    CERN Document Server

    Thabet, T

    2015-01-01

    The book provides a comprehensive application of narrative theory to video games, and presents the player-response paradigm of game criticism. Video Game Narrative and Criticism explains the nature of gameplay - a psychological experience and a meaning-making process in the fictional world of video games.

  11. Video Pulses: User-Based Modeling of Interesting Video Segments

    Directory of Open Access Journals (Sweden)

    Markos Avlonitis

    2014-01-01

    Full Text Available We present a user-based method that detects regions of interest within a video in order to provide video skims and video summaries. Previous research in video retrieval has focused on content-based techniques, such as pattern recognition algorithms that attempt to understand the low-level features of a video. We are proposing a pulse modeling method, which makes sense of a web video by analyzing users' Replay interactions with the video player. In particular, we have modeled the user information seeking behavior as a time series and the semantic regions as a discrete pulse of fixed width. Then, we have calculated the correlation coefficient between the dynamically detected pulses at the local maximums of the user activity signal and the pulse of reference. We have found that users' Replay activity significantly matches the important segments in information-rich and visually complex videos, such as lecture, how-to, and documentary. The proposed signal processing of user activity is complementary to previous work in content-based video retrieval and provides an additional user-based dimension for modeling the semantics of a social video on the web.

  12. Evaluating Existing Strategies to Limit Video Game Playing Time.

    Science.gov (United States)

    Davies, Bryan; Blake, Edwin

    2016-01-01

    Public concern surrounding the effects video games have on players has inspired a large body of research, and policy makers in China and South Korea have even mandated systems that limit the amount of time players spend in game. The authors present an experiment that evaluates the effectiveness of such policies. They show that forcibly removing players from the game environment causes distress, potentially removing some of the benefits that games provide and producing a desire for more game time. They also show that, with an understanding of player psychology, playtime can be manipulated without significantly changing the user experience or negating the positive effects of video games.

  13. Clinical evaluation and design of network live broadcast system of DSA video streaming%DSA视频流网络直播系统的设计与临床评价

    Institute of Scientific and Technical Information of China (English)

    王斌杰; 张和平; 靳海英; 张帆; 李波

    2008-01-01

    Objective To evaluate the clinical feasibility of network live broadcast of digital subtraction angiography(DSA)video streaming.Methods DSA video streaming was captured by an advanced image capture board.MPEG-4 and Directshow framework were used for data compression and transmission.Data of DSA video streaming could be transmitted easily from server sender filter to client receiver filter according to TCP and UDP protocols.Images of 24 cases were captured,which were compared with images of DSA workstation by experienced doctors.The subiective evaluation criteria included the manifestition of normal and pathological blood vessels,and sharpness,contrast degree and real time efficiency of images.Results The delay time of live broadcast was less than one second in 100 M LAN.Among 24 cases,excellent imaging quality was got in 17 cases,good in 5 cases and midst in 2 cases.Conclusion Excellent images and synchronism of DSA video are achieved in this system.which can meet clinical requirements of diagnosis and synchronism.%目的 探讨DSA视频流网络直播临床应用的可行性.方法 DSA视频流由高性能的图像采集卡进行采集,利用动态图像专家组标准4(MPEG-4)压缩,结合微软的流媒体处理开发包DirectShow框架技术,通过服务器端的发送过滤器(filter)和客户端的接收filter,再利用网络传输层的传输控制协议(TCP)和用户数据报协议(UDP),实现DSA视频流的网络直播.对24例图像进行采集直播,由有经验的医师对客户端与DSA工作站的视频图像进行对比分析,主观评价每例图像的血管、病变影像特征的显示情况,以及图像的清晰度、对比度、实时有效性.结果 在100 M的局域网中,该方案直播的图像延迟时间≤1 s,24例视频图像中图像品质评价优17例,良5例,中2例.结论 该方案直播DSA视频流,图像清晰度好,延迟时间短,能够达到临床诊断与实时性要求.

  14. A Robust Streaming Media System

    Science.gov (United States)

    Youwei, Zhang

    Presently, application layer multicast protocols (ALM) are proposed as substitute for IP multicast and have made extraordinary achievements. Integrated with Multi-data-stream mode such as Multiple Description Coding (MDC), ALM becomes more scalable and robust in high-dynamic Internet environment compared with single data stream. Although MDC can provide a flexible data transmission style, the synchronization of different descriptions encoded from one video source is proved to be difficult due to different delay on diverse transmission paths. In this paper, an ALM system called HMDC is proposed to improve accepted video quality of streaming media, hosts can join the separate overlay trees in different layers simultaneously, then the maximum synchronized descriptions of the same layer are worked out to acquire the best video quality. Simulations implemented on Internet-like topology indicate that HMDC achieves better video quality, lower link stress, higher robustness and comparable latency compared with traditional ALM protocols.

  15. Preliminary Validation of a New Clinical Tool for Identifying Problem Video Game Playing

    Science.gov (United States)

    King, Daniel Luke; Delfabbro, Paul H.; Zajac, Ian T.

    2011-01-01

    Research has estimated that between 6 to 13% of individuals who play video games do so excessively. However, the methods and definitions used to identify "problem" video game players often vary considerably. This research presents preliminary validation data for a new measure of problematic video game play called the Problem Video Game Playing…

  16. Preliminary Validation of a New Clinical Tool for Identifying Problem Video Game Playing

    Science.gov (United States)

    King, Daniel Luke; Delfabbro, Paul H.; Zajac, Ian T.

    2011-01-01

    Research has estimated that between 6 to 13% of individuals who play video games do so excessively. However, the methods and definitions used to identify "problem" video game players often vary considerably. This research presents preliminary validation data for a new measure of problematic video game play called the Problem Video Game…

  17. The Role of Structural Characteristics in Problematic Video Game Play: An Empirical Study

    Science.gov (United States)

    King, Daniel L.; Delfabbro, Paul H.; Griffiths, Mark D.

    2011-01-01

    The research literature suggests that the structural characteristics of video games may play a considerable role in the initiation, development and maintenance of problematic video game playing. The present study investigated the role of structural characteristics in video game playing behaviour within a sample of 421 video game players aged…

  18. Interactive real-time media streaming with reliable communication

    Science.gov (United States)

    Pan, Xunyu; Free, Kevin M.

    2014-02-01

    Streaming media is a recent technique for delivering multimedia information from a source provider to an end- user over the Internet. The major advantage of this technique is that the media player can start playing a multimedia file even before the entire file is transmitted. Most streaming media applications are currently implemented based on the client-server architecture, where a server system hosts the media file and a client system connects to this server system to download the file. Although the client-server architecture is successful in many situations, it may not be ideal to rely on such a system to provide the streaming service as users may be required to register an account using personal information in order to use the service. This is troublesome if a user wishes to watch a movie simultaneously while interacting with a friend in another part of the world over the Internet. In this paper, we describe a new real-time media streaming application implemented on a peer-to-peer (P2P) architecture in order to overcome these challenges within a mobile environment. When using the peer-to-peer architecture, streaming media is shared directly between end-users, called peers, with minimal or no reliance on a dedicated server. Based on the proposed software pɛvμa (pronounced [revma]), named for the Greek word meaning stream, we can host a media file on any computer and directly stream it to a connected partner. To accomplish this, pɛvμa utilizes the Microsoft .NET Framework and Windows Presentation Framework, which are widely available on various types of windows-compatible personal computers and mobile devices. With specially designed multi-threaded algorithms, the application can stream HD video at speeds upwards of 20 Mbps using the User Datagram Protocol (UDP). Streaming and playback are handled using synchronized threads that communicate with one another once a connection is established. Alteration of playback, such as pausing playback or tracking to a

  19. Joint source-channel video transmission

    CERN Document Server

    Zhai, Fan

    2007-01-01

    This book deals with the problem of joint source-channel video transmission, i.e., the joint optimal allocation of resources at the application layer and the other network layers, such as data rate adaptation, channel coding, power adaptation in wireless networks, quality of service (QoS) support from the network, and packet scheduling, for efficient video transmission. Real-time video communication applications, such as videoconferencing, video telephony, and on-demand video streaming, have gained increased popularity. However, a key problem in video transmission over the existing Internet an

  20. Locomotion Characteristics and Match-Induced Impairments in Physical Performance in Male Elite Team Handball Players

    DEFF Research Database (Denmark)

    Michalsik, L B; Aagaard, Peter; Madsen, Klavs

    2013-01-01

    The purpose of this study was to determine the physical demands and match-induced impairments in physical performance in male elite Team Handball (TH) players in relation to playing position. Male elite TH field players were closely observed during 6 competitive seasons. Each player (wing players......: WP, pivots: PV, backcourt players: BP) was evaluated during match-play using video recording and subsequently performing locomotion match analysis. A total distance of 3 627±568 m (group means±SD) was covered per match with a total effective playing time (TPT) of 53:51±5:52 min:s, while full...

  1. 1Mbps is enough: Video quality and individual idiosyncrasies in multiparty HD video-conferencing

    NARCIS (Netherlands)

    Schmitt, M.R.; Redi, J.A.; Cesar Garcia, P.S.; Bulterman, D.C.A.; Redi, J.A.; Bulterman, D.C.A.; Cesar Garcia, P.S.; Schmitt, M.R.

    2016-01-01

    Most video platforms deliver HD video in high bitrate encoding. Modern video-conferencing systems are capable of handling HD streams, but using multiparty conferencing, average internet connections in the home are on their bandwidth limit. For properly managing the encoding bitrate in videoconferenc

  2. WMSN中基于VSQI压缩反馈的协作节点选择%Compressive feedback for Video Stream Quality Index Based Selection of Collaboration node in WMSN

    Institute of Scientific and Technical Information of China (English)

    陈守宁; 郑宝玉; 崔景伍; 吉晓东

    2011-01-01

    In the field of collection, communication and analysis of the information in the wireless sensor networks, the accuracy of the information can be improved, and the node power consumption can be reduced by using cooperative communication techniques. The selection of cooperative partners is an important issue worthy of study, consider making use of the information feedback technology into wireless multimedia sensor networks (WMSN) , to feed the Video Stream Quality Index ( VSQI) back to sink node through the control channel from geographically distributed sensor nodes for supporting on the selection of collaboration node. In this paper, according to human visual characteristics, a video streaming quality estimation method is proposed, and signal VSQI is designed on the basis of that. Moreover, Compressed Sensing (CS) theory is applied to VSQI compression feedback in the experiment because of the large quantity of feedback information. The random measurement matrix associated with VSQI signal, and reconstruction guidelines is tested in the simulation experiment. The simulation results demonstrate that CS based Compressive feedback method can reduce the processing complexity of sensing node side and enhance the degree of compression, and provide the theoretical support for selection the collaboration node.%无线传感器网络中采用协同通信技术进行收集、交换和分析数据,可以有效提高信息精确度,并大大减少节点的能耗.其中协作节点的选择是一个重要问题.考虑在WMSN中应用信息压缩反馈技术,将分布在临近地理位置上的传感器节点的视频流质量指标(Video Stream Quality Index,VSQI)通过控制信道反馈给汇聚节点,可以为协同节点的选择提供支持.本文根据人类视觉特征,提出了一种用于视频流质量估计的方法,并据此综合考虑VSQI信号的设计.由于WMSN中巨大的信息反馈量,将压缩感知(Compressive Sensing,CS)理论应用到VSQI压缩反馈中

  3. Action Video Games Improve Direction Discrimination of Parafoveal Translational Global Motion but Not Reaction Times.

    Science.gov (United States)

    Pavan, Andrea; Boyce, Matthew; Ghin, Filippo

    2016-10-01

    Playing action video games enhances visual motion perception. However, there is psychophysical evidence that action video games do not improve motion sensitivity for translational global moving patterns presented in fovea. This study investigates global motion perception in action video game players and compares their performance to that of non-action video game players and non-video game players. Stimuli were random dot kinematograms presented in the parafovea. Observers discriminated the motion direction of a target random dot kinematogram presented in one of the four visual quadrants. Action video game players showed lower motion coherence thresholds than the other groups. However, when the task was performed at threshold, we did not find differences between groups in terms of distributions of reaction times. These results suggest that action video games improve visual motion sensitivity in the near periphery of the visual field, rather than speed response.

  4. Scalable Video Transcaling for the Wireless Internet

    Directory of Open Access Journals (Sweden)

    van der Schaar Mihaela

    2004-01-01

    Full Text Available The rapid and unprecedented increase in the heterogeneity of multimedia networks and devices emphasizes the need for scalable and adaptive video solutions both for coding and transmission purposes. However, in general, there is an inherent trade-off between the level of scalability and the quality of scalable video streams. In other words, the higher the bandwidth variation, the lower the overall video quality of the scalable stream that is needed to support the desired bandwidth range. In this paper, we introduce the notion of wireless video transcaling (TS, which is a generalization of (nonscalable transcoding. With TS, a scalable video stream, that covers a given bandwidth range, is mapped into one or more scalable video streams covering different bandwidth ranges. Our proposed TS framework exploits the fact that the level of heterogeneity changes at different points of the video distribution tree over wireless and mobile Internet networks. This provides the opportunity to improve the video quality by performing the appropriate TS process. We argue that an Internet/wireless network gateway represents a good candidate for performing TS. Moreover, we describe hierarchical TS (HTS, which provides a “Transcaler” with the option of choosing among different levels of TS processes with different complexities. We illustrate the benefits of TS by considering the recently developed MPEG-4 fine granularity scalability (FGS video coding. Extensive simulation results of video TS over bit rate ranges supported by emerging wireless LANs are presented.

  5. Design of Abnormal Detection and Dual-stream-encoding Based Video Surveillance System%基于异常检测与双流编码的视频监控系统设计

    Institute of Scientific and Technical Information of China (English)

    江城; 张重阳; 余松煜

    2011-01-01

    In this paper, one abnormal event detection and dual-stream-encoding based wireless intelligent video surveillance system is proposed. Firstly, the abnormal event, illegal invasion is implemented by live video analyzing. At the same time, two encoders are designed to generate two coded bit-streams: one is encoded with high quality and bit-rate, which is stored in the local storage; the other is encoded with low quality and bit-rate, which is transmitted to the receiver over the wireless network.The local storage and wireless transmission are triggered with the abnormal event detection, thus efficient usage of the wireless bandwidth and local storage resource can be achieved using the proposed system.%介绍了一种基于异常检测与双流编码的无线智能视频监控系统的设计方案.该系统首先基于对采集视频的分析,实现非法入侵等异常事件的自动检测,同时通过对同一路视频采用两个编码器进行双流编码,产生两路不同质量和码率的视频流.在此基础上,基于异常事件检测的结果,在有异常事件时触发高质量图像的本地保存和低码率图像的实时无线传输.在蜂窝网络的有限带宽下,该系统在同时实现视频监控所需的实时浏览和事后调阅功能基础上,通过异常事件检测触发存储与传输,实现了无线带宽资源和存储资源的高效利用.

  6. Towards an affordable alternative educational video game input device

    CSIR Research Space (South Africa)

    Smith, Adrew C

    2008-05-01

    Full Text Available The authors present the prototype design results of an alternative physical educational video gaming input device. The device elicits increased physical activity from the players as compared to the compact gaming controller. Complicated...

  7. The active video games' narrative impact on children's physical activities

    Science.gov (United States)

    Active video games (AVGs) capable of inducing physical activity offer an innovative approach to combating childhood obesity. Unfortunately, children's AVG game play decreases quickly, underscoring the need to identify novel methods for player engagement. Narratives have been demonstrated to influenc...

  8. Know Stroke: Know the Signs, Act in Time Video

    Medline Plus

    Full Text Available ... player... Video Transcript Weakness on one Side. Trouble Speaking. Trouble Seeing. Trouble Walking. Know Stroke, Know the ... side of the body Sudden confusion or trouble speaking or understanding, Sudden trouble seeing in one or ...

  9. Video Games and the First Amendment: "Brown v. Entertainment Merchants Association"

    Science.gov (United States)

    Schwinn, Steven D.

    2011-01-01

    Video games today give players an unprecedented opportunity to become part of the game. They literally put players in the game. And with rapid technological improvements and endless creativity, games are only becoming more realistic. They are also becoming more violent. Today's games allow players to kill, maim, dismember, and torture victims by…

  10. 基于Android的HLS播放器的实现和优化%Implementation and Optimization of HLS Media Player Based on Android

    Institute of Scientific and Technical Information of China (English)

    潘浩; 游向东; 邹晓佳; 罗迁

    2014-01-01

    HTTP Living Streaming(缩写HLS)是由苹果公司提出的基于 HTTP 的流媒体网络传输协议。在网络视频直播服务中,基于HLS协议构建的流媒体传输服务能更好的适应现有的网络,为用户提供接近实时的播放体验。本文介绍了Android平台上VLC开源播放器的HLS流解析部分实现,然后针对3G网络环境对播放器进行优化和改进。最后采用凤凰中文频道(支持HLS协议)作为测试源,结果表明改进后的播放器在3G网络环境播放体验大幅提升。%HTTP Live Streaming(also known as HLS) is an HTTP-based media streaming communications proto-col implemented by Apple Inc. On network live video services,the streaming media transport services based on HLS proto-cols can better adapt to the existing network,which can provide users with near real-time playback experience. This article describes implementation of HLS streaming parsing of VLC,which is a open-source media player on Android. Then opti-mize and improve the player aim at the 3G network environment. At last,taking the phoenix Chinese channel(support HLS protocol) as a test source,the results show that playback experience of the player significantly boost over the 3G network after improvement.

  11. Helping Hands: Designing Video Games with Interpersonal Touch Interaction

    OpenAIRE

    Watts, Cody; Sharlin, Ehud; Woytiuk, Peter

    2010-01-01

    International audience; Increasingly, the movements of players' physical bodies are being used as a method of controlling and playing video games. This trend is evidenced by the recent development of interpersonal touch-based games; multiplayer games which players control by physically touching their partners. Although a small number of interpersonal touch-based games have recently been designed, the best practices for creating video games based on this unconventional interaction technique re...

  12. Video Game-Based Learning: An Emerging Paradigm for Instruction

    Science.gov (United States)

    Squire, Kurt D.

    2013-01-01

    Interactive digital media, or video games, are a powerful new medium. They offer immersive experiences in which players solve problems. Players learn more than just facts--ways of seeing and understanding problems so that they "become" different kinds of people. "Serious games" coming from business strategy, advergaming, and entertainment gaming…

  13. Singing Video Games May Help Improve Pitch-Matching Accuracy

    Science.gov (United States)

    Paney, Andrew S.

    2015-01-01

    The purpose of this study was to investigate the effect of singing video games on the pitch-matching skills of undergraduate students. Popular games like "Rock Band" and "Karaoke Revolutions" rate players' singing based on the correctness of the frequency of their sung response. Players are motivated to improve their…

  14. Singing Video Games May Help Improve Pitch-Matching Accuracy

    Science.gov (United States)

    Paney, Andrew S.

    2015-01-01

    The purpose of this study was to investigate the effect of singing video games on the pitch-matching skills of undergraduate students. Popular games like "Rock Band" and "Karaoke Revolutions" rate players' singing based on the correctness of the frequency of their sung response. Players are motivated to improve their…

  15. Zerotree-based stereoscopic video CODEC

    Science.gov (United States)

    Thanapirom, S.; Fernando, W. A. C.; Edirisinghe, Eran A.

    2005-07-01

    Due to the provision of a more natural representation of a scene in the form of left and right eye views, a stereoscopic imaging system provides a more effective method for image/video display. Unfortunately the vast amount of information that must be transmitted/stored to represent a stereo image pair/video sequence, has so far hindered its use in commercial applications. However, by properly exploiting the spatial, temporal and binocular redundancy, a stereo image pair or a sequence could be compressed and transmitted through a single monocular channel's bandwidth without unduly sacrificing the perceived stereoscopic image quality. We propose a timely and novel framework to transmit stereoscopic data efficiently. We propose a timely and novel framework to transmit stereoscopic data efficiently. We present a new technique for coding stereo video sequences based on discrete wavelet transform (DWT) technology. The proposed technique particularly exploits zerotree entropy (ZTE) coding that makes use of the wavelet block concept to achieve low bit rate stereo video coding. One of the two image streams, namely, the main stream, is independently coded by a zerotree video CODEC, while the second stream, namely, the auxiliary stream, is predicted based on disparity compensation. A zerotree video CODEC subsequently codes the residual stream. We compare the performance of the proposed CODEC with a discrete cosine transform (DCT)-based, modified MPEG-2 stereo video CODEC. We show that the proposed CODEC outperforms the benchmark CODEC in coding both main and auxiliary streams.

  16. IMPLEMENTATION OF HTTP LIVE STREAMING PROTOCOL IN JAVA

    OpenAIRE

    Rehar, Anže

    2012-01-01

    In this thesis we discuss protocols for streaming to mobile devices. Tremendous growth of smartphone and tablet sales numbers over the past few years push content providers to seek new ways to offer video content. However, these devices have some limitations that make the implementation of video streaming a complex project. Most depends on the streaming protocol selection. There is a set of HTTP based technologies but there are no standards for adaptive streaming to mobile devices. In thesis ...

  17. Does Game Playing Experience Have an Impact on the Player-PNPC Relationship?

    Science.gov (United States)

    Daviault, Christine

    2012-01-01

    There are several types of characters in video games: the main protagonist/hero, the countless non-player characters (NPCs), and persistent non-player characters (PNPCs). While there is a substantial body of research about PNPCs from a game design point of view, they have been largely ignored by the academic community from a narrative perspective.…

  18. Method for endobronchial video parsing

    Science.gov (United States)

    Byrnes, Patrick D.; Higgins, William E.

    2016-03-01

    Endoscopic examination of the lungs during bronchoscopy produces a considerable amount of endobronchial video. A physician uses the video stream as a guide to navigate the airway tree for various purposes such as general airway examinations, collecting tissue samples, or administering disease treatment. Aside from its intraoperative utility, the recorded video provides high-resolution detail of the airway mucosal surfaces and a record of the endoscopic procedure. Unfortunately, due to a lack of robust automatic video-analysis methods to summarize this immense data source, it is essentially discarded after the procedure. To address this problem, we present a fully-automatic method for parsing endobronchial video for the purpose of summarization. Endoscopic- shot segmentation is first performed to parse the video sequence into structurally similar groups according to a geometric model. Bronchoscope-motion analysis then identifies motion sequences performed during bronchoscopy and extracts relevant information. Finally, representative key frames are selected based on the derived motion information to present a drastically reduced summary of the processed video. The potential of our method is demonstrated on four endobronchial video sequences from both phantom and human data. Preliminary tests show that, on average, our method reduces the number of frames required to represent an input video sequence by approximately 96% and consistently selects salient key frames appropriately distributed throughout the video sequence, enabling quick and accurate post-operative review of the endoscopic examination.

  19. Court Reconstruction for Camera Calibration in Broadcast Basketball Videos.

    Science.gov (United States)

    Wen, Pei-Chih; Cheng, Wei-Chih; Wang, Yu-Shuen; Chu, Hung-Kuo; Tang, Nick C; Liao, Hong-Yuan Mark

    2016-05-01

    We introduce a technique of calibrating camera motions in basketball videos. Our method particularly transforms player positions to standard basketball court coordinates and enables applications such as tactical analysis and semantic basketball video retrieval. To achieve a robust calibration, we reconstruct the panoramic basketball court from a video, followed by warping the panoramic court to a standard one. As opposed to previous approaches, which individually detect the court lines and corners of each video frame, our technique considers all video frames simultaneously to achieve calibration; hence, it is robust to illumination changes and player occlusions. To demonstrate the feasibility of our technique, we present a stroke-based system that allows users to retrieve basketball videos. Our system tracks player trajectories from broadcast basketball videos. It then rectifies the trajectories to a standard basketball court by using our camera calibration method. Consequently, users can apply stroke queries to indicate how the players move in gameplay during retrieval. The main advantage of this interface is an explicit query of basketball videos so that unwanted outcomes can be prevented. We show the results in Figs. 1, 7, 9, 10 and our accompanying video to exhibit the feasibility of our technique.

  20. Streams with Strahler Stream Order

    Data.gov (United States)

    Minnesota Department of Natural Resources — Stream segments with Strahler stream order values assigned. As of 01/08/08 the linework is from the DNR24K stream coverages and will not match the updated...

  1. Video Game Characters. Theory and Analysis

    Directory of Open Access Journals (Sweden)

    Felix Schröter

    2014-06-01

    Full Text Available This essay develops a method for the analysis of video game characters based on a theoretical understanding of their medium-specific representation and the mental processes involved in their intersubjective construction by video game players. We propose to distinguish, first, between narration, simulation, and communication as three modes of representation particularly salient for contemporary video games and the characters they represent, second, between narrative, ludic, and social experience as three ways in which players perceive video game characters and their representations, and, third, between three dimensions of video game characters as ‘intersubjective constructs’, which usually are to be analyzed not only as fictional beings with certain diegetic properties but also as game pieces with certain ludic properties and, in those cases in which they function as avatars in the social space of a multiplayer game, as representations of other players. Having established these basic distinctions, we proceed to analyze their realization and interrelation by reference to the character of Martin Walker from the third-person shooter Spec Ops: The Line (Yager Development 2012, the highly customizable player-controlled characters from the role-playing game The Elder Scrolls V: Skyrim (Bethesda 2011, and the complex multidimensional characters in the massively multiplayer online role-playing game Star Wars: The Old Republic (BioWare 2011-2014.

  2. Automated analysis and annotation of basketball video

    Science.gov (United States)

    Saur, Drew D.; Tan, Yap-Peng; Kulkarni, Sanjeev R.; Ramadge, Peter J.

    1997-01-01

    Automated analysis and annotation of video sequences are important for digital video libraries, content-based video browsing and data mining projects. A successful video annotation system should provide users with useful video content summary in a reasonable processing time. Given the wide variety of video genres available today, automatically extracting meaningful video content for annotation still remains hard by using current available techniques. However, a wide range video has inherent structure such that some prior knowledge about the video content can be exploited to improve our understanding of the high-level video semantic content. In this paper, we develop tools and techniques for analyzing structured video by using the low-level information available directly from MPEG compressed video. Being able to work directly in the video compressed domain can greatly reduce the processing time and enhance storage efficiency. As a testbed, we have developed a basketball annotation system which combines the low-level information extracted from MPEG stream with the prior knowledge of basketball video structure to provide high level content analysis, annotation and browsing for events such as wide- angle and close-up views, fast breaks, steals, potential shots, number of possessions and possession times. We expect our approach can also be extended to structured video in other domains.

  3. Video Game Translation:Transfer the Same Player Experience to a Different Culture%浅谈游戏翻译中的文化保留与转换

    Institute of Scientific and Technical Information of China (English)

    王韵

    2015-01-01

    With a short history of no more than half a century, video game has won great popularity. Because most video games are English or Japanese, the demand from overseas markets prompts the rise of game localization industry. Game localization is largely concerned with translation. It is a process of linguistic as well as cultural transfer. Only until recently was game translation incorpo-rated into Translation Studies. The chief aim of the present work is to investigate the features of video game translation, especially how cultural influences and translators'understanding affect a localized game. Suggestion for game translators is they need to fully understand both game world culture and the target regional culture.%视频游戏(video game)自上世纪七十年代初诞生,至今发展不过半个世纪,已风靡全球.目前市场上大多数游戏的原始语言为英语或日语,因此,海外市场的需求促进了游戏本地化产业兴起.游戏本地化最重要的一环便是翻译,它不仅涉及语言转换,还有文化的转换与取舍.这里的文化除了传统意义上的地域文化,还包括游戏世界本身的虚拟文化.直到近年才有学者将游戏翻译融入翻译研究领域之中.该文结合作者的翻译经历,旨在分析游戏翻译的特点以及文化因素和译员理解对本地化后的游戏产生的影响.

  4. Video-based multimedia designs: A research study testing learning effectiveness

    Directory of Open Access Journals (Sweden)

    David Reiss

    2008-05-01

    Full Text Available This paper summarizes research conducted on three computer-based video models’ effectiveness for learning based on memory and comprehension. In this quantitative study, a two-minute video presentation was created and played back in three different types of media players, for a sample of eighty-seven college freshman. The three players evaluated include a standard QuickTime video/audio player, a QuickTime player with embedded triggers that launched HTML-based study guide pages, and a Macromedia Flash-based video/audio player with a text field, with user activated links to the study guides as well as other interactive on-line resources. An assumption guiding this study was that the enhanced designs presenting different types of related information would reinforce the material and produce better comprehension and retention. However, findings indicate that the standard video player was the most effective overall, which suggests that media designs able to control the focus of a learner’s attention to one specific stream of information, a single-stream focused approach, may be the most effective way to present media-based content. Résumé: Cet article résume une étude vérifiant l’efficacité de l’apprentissage basé sur la mémorisation et la compréhension, conduite à partir de trois modèles basés sur la vidéo informatisée. Dans cette étude quantitative, une vidéo de deux minutes a été créée et lue sur trois types de lecteurs différents, pour un échantillon de 87 étudiants universitaires de première année. Les trois lecteurs évalués comprenaient un lecteur standard audio/vidéo Quicktime, un lecteur Quicktime avec déclencheurs intégrés qui lançait un guide d’étude en HTML, et un lecteur audio/vidéo Flash Macromedia avec un champ texte, comprenant des liens activés par l’usager vers des guides d’étude et d’autres ressources interactives en ligne. Une supposition guidant cette étude était que les designs

  5. 抗量化转码的 HEVC 视频流零水印算法%HEVC-based Video Stream Zero-watermarking Algorithm with Robustness to Re-quantization Transcoding

    Institute of Scientific and Technical Information of China (English)

    王静; 郁梅; 李文锋; 骆挺

    2016-01-01

    针对 HEVC 的视频流版权问题,提出了一种抗量化转码的零水印算法。首先,经过统计发现量化转码后编码单元(CU)深度具有很强的稳定性,部分深度会发生转移且主要往相邻深度转移;然后,为增加深度特征的顽健性,对 CU 深度进行分组,并映射成二值信息;最后,将加密后的特征信息同混沌置乱后的版权信息异或,与时间戳作为最终注册的零水印。实验结果表明,该算法对量化参数在一定变化范围内的重量化转码攻击以及常见的信号攻击具有很强的鲁棒性。%For the video stream copyright issues of high efficiency video coding (HEVC), a new zero-watermarking algorithm with robustness to re-quantization transcoding is proposed. Firstly, from statistics analysis about re-quantization transcoding, it is found that Coding Unit (CU) depths have strong stability and only a fraction of the depths would shift and almost shift to adjacent depths. Then, in order to increase the robustness of the depth characteristic, the CU depths are divided into two groups and mapped into two values ‘0’ and ‘1’. Finally, ‘xor’ operation is performed between the binary information encrypted and the copyright information scrambled by using the chaotic algorithm, the outcome with the timestamp acts as the ultimate registered zero-watermarking. Experimental results show that the proposed algorithm has strong robustness to re-quantization transcoding and other common signal attacks.

  6. Watermarking textures in video games

    Science.gov (United States)

    Liu, Huajian; Berchtold, Waldemar; Schäfer, Marcel; Lieb, Patrick; Steinebach, Martin

    2014-02-01

    Digital watermarking is a promising solution to video game piracy. In this paper, based on the analysis of special challenges and requirements in terms of watermarking textures in video games, a novel watermarking scheme for DDS textures in video games is proposed. To meet the performance requirements in video game applications, the proposed algorithm embeds the watermark message directly in the compressed stream in DDS files and can be straightforwardly applied in watermark container technique for real-time embedding. Furthermore, the embedding approach achieves high watermark payload to handle collusion secure fingerprinting codes with extreme length. Hence, the scheme is resistant to collusion attacks, which is indispensable in video game applications. The proposed scheme is evaluated in aspects of transparency, robustness, security and performance. Especially, in addition to classical objective evaluation, the visual quality and playing experience of watermarked games is assessed subjectively in game playing.

  7. Video Traffic Prediction Using Neural Networks

    Directory of Open Access Journals (Sweden)

    Miloš Oravec

    2008-10-01

    Full Text Available In this paper, we consider video stream prediction for application in services likevideo-on-demand, videoconferencing, video broadcasting, etc. The aim is to predict thevideo stream for an efficient bandwidth allocation of the video signal. Efficient predictionof traffic generated by multimedia sources is an important part of traffic and congestioncontrol procedures at the network edges. As a tool for the prediction, we use neuralnetworks – multilayer perceptron (MLP, radial basis function networks (RBF networksand backpropagation through time (BPTT neural networks. At first, we briefly introducetheoretical background of neural networks, the prediction methods and the differencebetween them. We propose also video time-series processing using moving averages.Simulation results for each type of neural network together with final comparisons arepresented. For comparison purposes, also conventional (non-neural prediction isincluded. The purpose of our work is to construct suitable neural networks for variable bitrate video prediction and evaluate them. We use video traces from [1].

  8. Serious Video Games for Health How Behavioral Science Guided the Development of a Serious Video Game.

    Science.gov (United States)

    Thompson, Debbe; Baranowski, Tom; Buday, Richard; Baranowski, Janice; Thompson, Victoria; Jago, Russell; Griffith, Melissa Juliano

    2010-08-01

    Serious video games for health are designed to entertain players while attempting to modify some aspect of their health behavior. Behavior is a complex process influenced by multiple factors, often making it difficult to change. Behavioral science provides insight into factors that influence specific actions that can be used to guide key game design decisions. This article reports how behavioral science guided the design of a serious video game to prevent Type 2 diabetes and obesity among youth, two health problems increasing in prevalence. It demonstrates how video game designers and behavioral scientists can combine their unique talents to create a highly focused serious video game that entertains while promoting behavior change.

  9. Digital video technology - today and tomorrow: 11th office information technology conference

    Energy Technology Data Exchange (ETDEWEB)

    Liberman, J.

    1994-10-01

    Digital video is probably computing`s fastest moving technology today. Just three years ago, the zenith of digital video technology on the PC was the successful marriage of digital text and graphics with analog audio and video by means of expensive analog laser disc players and video overlay boards. The state of the art involves two different approaches to fully digital video on computers: hardware-assisted and software-only solutions.

  10. Artificial Video for Video Analysis

    Science.gov (United States)

    Gallis, Michael R.

    2010-01-01

    This paper discusses the use of video analysis software and computer-generated animations for student activities. The use of artificial video affords the opportunity for students to study phenomena for which a real video may not be easy or even possible to procure, using analysis software with which the students are already familiar. We will…

  11. Cats and Portals: Video Games, Learning, and Play

    Science.gov (United States)

    Gee, James Paul

    2008-01-01

    The author builds on arguments he has made elsewhere that good commercial video games foster deep learning and problem solving and that such games in fact promote mastery as a form of play. Here he maintains that some good video games engage players with an important type of play, namely of play as discovery, of play as surmising new possibilities…

  12. Integration of Active Video Games in Extracurricular Activity at Schools

    Science.gov (United States)

    Lee, Jung Eun; Huang, Charles; Pope, Zachary; Gao, Zan

    2015-01-01

    Active video games require players to be physically active. Dance Dance Revolution (DDR) is an interactive dancing game that requires fast-foot movement coordinated with energetic music and visuals. The Wii and Xbox Kinect games have also become good active video games for the promotion of physical activity participation. These games are much more…

  13. Motivational Engagement and Video Gaming: A Mixed Methods Study

    Science.gov (United States)

    Hoffman, Bobby; Nadelson, Louis

    2010-01-01

    A mixed methods design was used to identify factors associated with motivational engagement in video gaming. Self-report instruments were administered to 189 video game players to assess goal orientations, affect, need for cognition, and perceptions of engagement and flow. Simultaneously, a sub-set of 25 participants were interviewed and results…

  14. Recognizing Strokes in Tennis Videos Using Hidden Markov Models

    NARCIS (Netherlands)

    Petkovic, M.; Jonker, W.; Zivkovic, Z.

    2001-01-01

    This paper addresses content-based video retrieval with an emphasis on recognizing events in tennis game videos. In particular, we aim at recognizing different classes of tennis strokes using automatic learning capability of Hidden Markov Models. Driven by our domain knowledge, a robust player segme

  15. Chaos-Based Encryption Algorithm for Compressed Video

    Institute of Scientific and Technical Information of China (English)

    袁春; 钟玉琢; 贺玉文

    2003-01-01

    Encryption for compressed video streams has attracted increasing attention with the exponential growth of digital multimedia delivery and consumption. However, most algorithms proposed in the literature do not effectively address the peculiarities of security and performance requirements. This paper presents a chaos-based encryption algorithm called the chaotic selective encryption of compressed video (CSECV) which exploits the characteristics of the compressed video. The encryption has three separate layers that can be selected according to the security needs of the application and the processing capability of the client computer. The chaotic pseudo-random sequence generator used to generate the key-sequence to randomize the important fields in the compressed video stream has its parameters encrypted by an asymmetric cipher and placed into the stream. The resulting stream is still a valid video stream. CSECV has significant advantages over existing algorithms for security, decryption speed, implementation flexibility, and error preservation.

  16. Using Video Conferencing in Lecture Classes

    Science.gov (United States)

    Gibbs, Bill; Larson, Erik

    2007-01-01

    Duquesne University's department of journalism and multimedia arts supports many of its classes with Mediasite Live, a video conferencing system that captures the output of presentation devices and streams it live to the Web, as well as recording presentations for Web streaming or recording to CD or DVD. Bill Gibbs and Erik Larson examine the…

  17. Characterizing Video Coding Computing in Conference Systems

    NARCIS (Netherlands)

    Tuquerres, G.

    2000-01-01

    In this paper, a number of coding operations is provided for computing continuous data streams, in particular, video streams. A coding capability of the operations is expressed by a pyramidal structure in which coding processes and requirements of a distributed information system are represented. Th

  18. CUE USAGE IN VOLLEYBALL: A TIME COURSE COMPARISON OF ELITE, INTERMEDIATE AND NOVICE FEMALE PLAYERS

    Science.gov (United States)

    Vaeyens, R; Zeuwts, L; Philippaerts, R; Lenoir, M

    2014-01-01

    This study compared visual search strategies in adult female volleyball players of three levels. Video clips of the attack of the opponent team were presented on a large screen and participants reacted to the final pass before the spike. Reaction time, response accuracy and eye movement patterns were measured. Elite players had the highest response accuracy (97.50 ± 3.5%) compared to the intermediate (91.50 ± 4.7%) and novice players (83.50 ± 17.6%; pvolleyball and suggests that expert players extract more information from parafoveal regions. PMID:25609887

  19. Digital Video: Get with It!

    Science.gov (United States)

    Van Horn, Royal

    2001-01-01

    Several years after the first audiovisual Macintosh computer appeared, most educators are still oblivious of this technology. Almost every other economic sector (including the porn industry) makes abundant use of digital and streaming video. Desktop movie production is so easy that primary grade students can do it. Tips are provided. (MLH)

  20. Scheme for Performance Improvement of P2P Live Video Streaming On LANs%局域网下的P2P流媒体直播性能优化方案

    Institute of Scientific and Technical Information of China (English)

    林可; 杨珉; 毛迪林

    2011-01-01

    With the quick development of Peer-to-Peer Live Video Streaming (P2PLVS), the traffic of streaming media has taken a great part of Internet traffic, which severely impacts those ISP's ordinary service. Currently, there is few method which can relieve the traffic stress brought by P2PLVS applications without impacting playback performance of users. In this paper, we first analyze the common working mechanism of Mesh based P2PLVS, and then present an application-level protocol based scheme to improve the o-verall performance of P2PLVS for LAN users. The scheme can effectively reduce the ISP's streaming media traffic brought by the P2PLVS peers within the LAN, and meanwhile improve their playback performance in terms of download efficiency and playback delay. Prototype System based experiments prove that for program-concentrated P2PLVS in LAN, this scheme is reliable and effective.%随着P2P实时流媒体在网络上的流行,来自P2P实时流媒体应用的流量占据了在ISP主干链路的流量中相当大的比例.对于种类繁多并且私有化了应用层协议的P2P流媒体应用来说,目前很少有针对性的方法在不损害用户播放效果的前提下来缓解其对主干网的流量压力.通过对目前主流的基于Mesh结构的P2P流媒体直播系统工作原理的分析,提出一套基于应用层协议的针对局域网用户的P2P实时流媒体优化方案,能够从整体上有效减少P2P流媒体应用对该局域网外部节点的依赖,同时从下栽效率以及播放延时等方面改善该局域网内部的P2P流媒体服务的用户体验.实验结果表明,在局域网内具有一定数量的P2P实时流媒体用户以及相对集中的节目源的情况下,该方案在改善网络流量和用户体验方面均能起到很好的效果.

  1. Data transmission strategy of P2P pattern live video media streaming system%基于P2P流媒体直播系统的数据传输策略

    Institute of Scientific and Technical Information of China (English)

    孙知信; 陈亚当; 任志广

    2011-01-01

    针对P2P模式下视频流媒体直播系统的数据传输策略用改进的模拟退火算法进行了优化.以全局规划的思想建立了P2P视频流媒体的数据传输策略数学模型VMDTSA-P2P,模型充分考虑了可用出口带宽和可用性时间对播放连续性的影响,把它们作为获取最优解的目标函数因子,并用改进后的模拟退火算法进行解的寻优,相比于传统的数据传输策略,在具有大量用户的情况下加快了新节点从伙伴节点中选择数据块提供节点的速度,并且保证得到近似最优的数据块提供节点组合,减少了视频流媒体直播系统播放的延迟,从而提高了播放的连续性、流畅性,保证了视频播放的质量.通过该算法在模拟P2P系统中的实现,验证了该算法在P2P系统中对数据传输的准确性和高效性.%An algorithm optimization was made with improved simulated annealing algorithm aimed at data transmission strategy of streaming media system in P2P networks. According with global layout, a mathematic model have been estabfished for data transmission strategy of streaming media system in P2P networks named VMDTSA-P2P, which completely have considered the affection of both the out-bandwidth and the available time, and take them as the object function for getting the optimum solution. It also optimized the solutions with improved simulated annealing algorithm.Compared with traditional data transmission strategies, this improved algorithm accelerates the speed of new nodes choose the data provider from its partner nodes when there are lots of users and insures the solution of the data provider is approximate the best. Thus, the play delay of the streaming media system is decreased and the quality of video playback is increased. By realizing it in a simulated P2P system, the accuracy and the efficiency were both verified in the simulation.

  2. Cross-layer Optimized Rate Adaptation and Error Control for Mobile 3D Video Streaming%基于跨层码率适配和差错控制的3D 视频无线传输方法

    Institute of Scientific and Technical Information of China (English)

    刘金霞; 刘延伟; 慈松

    2014-01-01

    For video plus depth based mobile 3D video streaming ,this paper proposes a cross-layer optimized rate adaptation and error control method .The proposed method tunes the coding rate and intra refresh coding ratio at the application layer ,and mod-ulation and channel coding scheme at the physical layer by minimizing the end-to-end 3D video distortion .Thus ,the proposed method can reach the goal of adapting source rate to the channelbandwidth as well as leveraging the error control strengths between the application layer and physical layer .Correspondingly ,the virtual view quality of the 3D video at the receiver can be improved . Experimental results show that the proposed method can efficiently improve the 3D video streaming performance .%针对纹理视频加深度序列的3D视频无线传输,本文提出一种基于跨层优化的码率适配和差错控制方法。通过最小化端到端3D视频失真,均衡调整和配置应用层3D视频编码的码率和帧内编码更新比例,以及物理层的调制和编码模式,达到信源码率适配信道带宽以及应用层差错控制和物理层信道保护强度相互平衡的目的,进而提高接收端的3D虚拟视点视频质量。实验结果表明,提出的方法能有效的提高3D视频无线传输的性能。

  3. The Player Engagement Process

    DEFF Research Database (Denmark)

    Schoenau-Fog, Henrik

    2011-01-01

    Engagement is an essential element of the player experience, and the concept is described in various ways in the literature. To gain a more detailed comprehension of this multifaceted concept, and in order to better understand what aspects can be used to evaluate engaging game play and to design...... engaging user experiences, this study investigates one dimension of player engagement by empirically identifying the components associated with the desire to continue playing. Based on a description of the characteristics of player engagement, a series of surveys were developed to discover the components......, categories and triggers involved in this process. By applying grounded theory to the analysis of the responses, a process-oriented player engagement framework was developed and four main components consisting of objectives, activities, accomplishments and affects as well as the corresponding categories...

  4. MPEG2 video parameter and no reference PSNR estimation

    DEFF Research Database (Denmark)

    Li, Huiying; Forchhammer, Søren

    2009-01-01

    MPEG coded video may be processed for quality assessment or postprocessed to reduce coding artifacts or transcoded. Utilizing information about the MPEG stream may be useful for these tasks. This paper deals with estimating MPEG parameter information from the decoded video stream without access t...... DCT coefficients, the PSNR is estimated from the decoded video without reference images. Tests on decoded fixed rate MPEG2 sequences demonstrate perfect detection rates and good performance of the PSNR estimation....

  5. Affective video and problem solving within a Web-environment

    NARCIS (Netherlands)

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

    2002-01-01

    Currently there is a growing interest in Web-based multimedia learning environments, particularly those making use of asynchronous streaming video. This interest motivates renewed attention to properties of video for educational purposes. A typical property of video is its emotion-evoking potential.

  6. The Use of Video Disks: Computer Based Analysis of Works of Art.

    Science.gov (United States)

    McWhinnie, Harold J.

    This paper presents research using a computer with a video disk player to do aesthetic analysis of the work of Vincent Van Gogh. A discussion of the video disk system, and of several software systems including: (1) Dr. Halo, (2) Handy, (3) PC-Paint, and (4) Pilot are outlined. Several possible uses of the computer with interactive video disks for…

  7. Mobile video with mobile IPv6

    CERN Document Server

    Minoli, Daniel

    2012-01-01

    Increased reliance on mobile devices and streaming of video content are two of the most recent changes that have led those in the video distribution industry to be concerned about the shifting or erosion of traditional advertising revenues. Infrastructure providers also need to position themselves to take advantage of these trends. Mobile Video with Mobile IPv6provides an overview of the current mobile landscape, then delves specifically into the capabilities and operational details of IPv6. The book also addresses 3G and 4G services, the application of Mobile IPv6 to streaming and other mobil

  8. Performance Analysis of Video Transmission Using Sequential Distortion Minimization Method for Digital Video Broadcasting Terrestrial

    Directory of Open Access Journals (Sweden)

    Novita Astin

    2016-12-01

    Full Text Available This paper presents about the transmission of Digital Video Broadcasting system with streaming video resolution 640x480 on different IQ rate and modulation. In the video transmission, distortion often occurs, so the received video has bad quality. Key frames selection algorithm is flexibel on a change of video, but on these methods, the temporal information of a video sequence is omitted. To minimize distortion between the original video and received video, we aimed at adding methodology using sequential distortion minimization algorithm. Its aim was to create a new video, better than original video without significant loss of content between the original video and received video, fixed sequentially. The reliability of video transmission was observed based on a constellation diagram, with the best result on IQ rate 2 Mhz and modulation 8 QAM. The best video transmission was also investigated using SEDIM (Sequential Distortion Minimization Method and without SEDIM. The experimental result showed that the PSNR (Peak Signal to Noise Ratio average of video transmission using SEDIM was an increase from 19,855 dB to 48,386 dB and SSIM (Structural Similarity average increase 10,49%. The experimental results and comparison of proposed method obtained a good performance. USRP board was used as RF front-end on 2,2 GHz.

  9. Launch Support Video Site

    Science.gov (United States)

    OFarrell, Zachary L.

    2013-01-01

    The goal of this project is to create a website that displays video, countdown clock, and event times to customers during launches, without needing to be connected to the internal operations network. The requirements of this project are to also minimize the delay in the clock and events to be less than two seconds. The two parts of this are the webpage, which will display the data and videos to the user, and a server to send clock and event data to the webpage. The webpage is written in HTML with CSS and JavaScript. The JavaScript is responsible for connecting to the server, receiving new clock data, and updating the webpage. JavaScript is used for this because it can send custom HTTP requests from the webpage, and provides the ability to update parts of the webpage without having to refresh the entire page. The server application will act as a relay between the operations network, and the open internet. On the operations network side, the application receives multicast packets that contain countdown clock and events data. It will then parse the data into current countdown times and events, and create a packet with that information that can be sent to webpages. The other part will accept HTTP requests from the webpage, and respond to them with current data. The server is written in C# with some C++ files used to define the structure of data packets. The videos for the webpage will be shown in an embedded player from UStream.

  10. A Usability Survey of a Contents-Based Video Retrieval System by Combining Digital Video and an Electronic Bulletin Board

    Science.gov (United States)

    Haga, Hirohide; Kaneda, Shigeo

    2005-01-01

    This article describes the survey of the usability of a novel content-based video retrieval system. This system combines video streaming and an electronic bulletin board system (BBS). Comments submitted to the BBS are used to index video data. Following the development of the prototype system an experimental survey with ten subjects was performed.…

  11. When Video Games Tell Stories: A Model of Video Game Narrative Architectures

    OpenAIRE

    Marcello Arnaldo Picucci

    2014-01-01

    In the present study a model is proposed offering a comprehensive categorization of video game narrative structures intended as the methods and techniques used by game designers and allowed by the medium to deliver the story content throughout the gameplay in collaboration with the players. A case is first made for the presence of narrative in video games and its growth of importance as a central component in game design. An in-depth analysis ensues focusing on how games tell stories, guided ...

  12. Extracting Text from Video

    Directory of Open Access Journals (Sweden)

    Jayshree Ghorpade

    2011-09-01

    Full Text Available The text data present in images and video contain certain useful information for automatic annotation,indexing, and structuring of images. However variations of the text due to differences in text style, font, size, orientation, alignment as well as low image contrast and complex background make the problem of automatic text extraction extremely difficult and challenging job. A large number of techniques have been proposed to address this problem and the purpose of this paper is to design algorithms for each phase of extracting text from a video using java libraries and classes. Here first we frame the input video into stream of images using the Java Media Framework (JMF with the input being a real time or a video from the database. Then we apply pre processing algorithms to convert the image to gray scale and remove the disturbances like superimposed lines over the text, discontinuity removal, and dot removal.Then we continue with the algorithms for localization, segmentation and recognition for which we use the neural network pattern matching technique. The performance of our approach is demonstrated by presenting experimental results for a set of static images.

  13. EXTRACTING TEXT FROM VIDEO

    Directory of Open Access Journals (Sweden)

    Jayshree Ghorpade

    2011-06-01

    Full Text Available The text data present in images and video contain certain useful information for automatic annotation,indexing, and structuring of images. However variations of the text due to differences in text style, font, size, orientation, alignment as well as low image contrast and complex background make the problem of automatic text extraction extremely difficult and challenging job. A large number of techniques have been proposed to address this problem and the purpose of this paper is to design algorithms for each phase of extracting text from a video using java libraries and classes. Here first we frame the input video into stream of images using the Java Media Framework (JMF with the input being a real time or a video from the database. Then we apply pre processing algorithms to convert the image to gray scale and remove the disturbances like superimposed lines over the text, discontinuity removal, and dot removal.Then we continue with the algorithms for localization, segmentation and recognition for which we use the neural network pattern matching technique. The performance of our approach is demonstrated by presenting experimental results for a set of static images.

  14. Video Orbits of the Geminids

    Science.gov (United States)

    Hajdukova, M.

    2014-07-01

    Geminid meteoroids, observed by the video technique, were analysed with the aim of determining the actual dispersion of their reciprocal semimajor axes 1/a within the stream. Orbits were selected from the European Video Meteor Network Database, EDMOND, (Kornos et al., 2013), from the SonotaCo Shower Catalogue (SonotaCo, 2009), and from the Czech Catalogue of Video Meteor Orbits (Koten et al., 2003). The observed orbital dispersion, including the measurement errors, was compared with that obtained from the precisely-reduced photographic orbits of Geminids from the IAU Meteor Data Center (Lindblad et al., 2003). In this paper, we concentrate on the influence of errors on the orbital dispersion. The size and distribution of observational errors determined from the long-period meteoroid streams (Hajdukova 2013), were applied to determine the real dispersion within this short-period meteoroid stream. The observed dispersions, described by the median absolute deviation in terms of 1/a, range from 0.041 to 0.050 1/au. The deviation of the median reciprocal semimajor axis from the parent (3200) Phaethon, obtained from Japanese video orbits, is 0.009 1/au, and that from the EDMOND data 0.01 1/au. This deviation obtained from the photographic orbits of the IAU Meteor Data Center was significantly greater (Hajdukova 2009). Similar results were obtained from the Czech Video Orbits Catalogue, where the value is 0.05 1/au. The investigation showed that semimajor axes of meteor orbits in both the SonotaCo and EDMOND datasets are systematically biased as a consequence of the method used for the video orbit determination, probably because corrections for atmospheric deceleration were either incorrectly made or were not done at all. Thus, the determined heliocentric velocities are underestimated, and the semimajor axes medians shifted towards smaller values. The observed distributions in 1/a from these video data become biased towards higher values of 1/a. The orbits of the Geminid

  15. Robust Video Communication over an Urban VANET

    Directory of Open Access Journals (Sweden)

    N. Qadri

    2010-01-01

    Full Text Available Video communication within a Vehicular Ad Hoc Network (VANET has the potential to be of considerable benefit in an urban emergency, as it allows emergency vehicles approaching the scene to better understand the nature of the emergency. However, the lack of centralized routing and network resource management within a VANET is an impediment to video streaming. To overcome these problems the paper pioneers source-coding techniques for VANET video streaming. The paper firstly investigates two practical multiple-path schemes, Video Redundancy Coding (VRC and the H.264/AVC codec's redundant frames. The VRC scheme is reinforced by gradual decoder refresh to improve the delivered video quality. Evaluation shows that multiple-path 'redundant frames' achieves acceptable video quality at some destinations, whereas VRC is insufficient. The paper also demonstrates a third source coding scheme, single-path streaming with Flexible Macroblock Ordering, which is also capable of delivery of reasonable quality video. Therefore, video communication between vehicles is indeed shown to be feasible in an urban emergency if the suitable source coding techniques are selected.

  16. Seamless Video Session Handoff between WLANs

    Directory of Open Access Journals (Sweden)

    Claudio de Castro Monteiro

    2010-01-01

    Full Text Available Handoff in a distributed IEEE 802.11 Wireless LAN network is a source of significant amount of problems on the video transmission environment. The visual quality of video streaming applications is lowered when stations are in handoff status. In this paper, we introduce an architecture of a session proxy (SP, which tries to preserve the quality of the streaming video upon each handoff between access points. We have evaluated thresholds of RSSI and Loss Frame Rate (LFR for deciding the moment when the handoff process shall begin. Our solution performance was evaluated in a testbed implementation for MPEG-4 video on demand with one video server (VLS and two FreeBSD-based access points supporting Mobile IP, DHCP Server and IAPP approach.

  17. Indexed Captioned Searchable Videos: A Learning Companion for STEM Coursework

    Science.gov (United States)

    Tuna, Tayfun; Subhlok, Jaspal; Barker, Lecia; Shah, Shishir; Johnson, Olin; Hovey, Christopher

    2016-09-01

    Videos of classroom lectures have proven to be a popular and versatile learning resource. A key shortcoming of the lecture video format is accessing the content of interest hidden in a video. This work meets this challenge with an advanced video framework featuring topical indexing, search, and captioning (ICS videos). Standard optical character recognition (OCR) technology was enhanced with image transformations for extraction of text from video frames to support indexing and search. The images and text on video frames is analyzed to divide lecture videos into topical segments. The ICS video player integrates indexing, search, and captioning in video playback providing instant access to the content of interest. This video framework has been used by more than 70 courses in a variety of STEM disciplines and assessed by more than 4000 students. Results presented from the surveys demonstrate the value of the videos as a learning resource and the role played by videos in a students learning process. Survey results also establish the value of indexing and search features in a video platform for education. This paper reports on the development and evaluation of ICS videos framework and over 5 years of usage experience in several STEM courses.

  18. Indexed Captioned Searchable Videos: A Learning Companion for STEM Coursework

    Science.gov (United States)

    Tuna, Tayfun; Subhlok, Jaspal; Barker, Lecia; Shah, Shishir; Johnson, Olin; Hovey, Christopher

    2017-02-01

    Videos of classroom lectures have proven to be a popular and versatile learning resource. A key shortcoming of the lecture video format is accessing the content of interest hidden in a video. This work meets this challenge with an advanced video framework featuring topical indexing, search, and captioning (ICS videos). Standard optical character recognition (OCR) technology was enhanced with image transformations for extraction of text from video frames to support indexing and search. The images and text on video frames is analyzed to divide lecture videos into topical segments. The ICS video player integrates indexing, search, and captioning in video playback providing instant access to the content of interest. This video framework has been used by more than 70 courses in a variety of STEM disciplines and assessed by more than 4000 students. Results presented from the surveys demonstrate the value of the videos as a learning resource and the role played by videos in a students learning process. Survey results also establish the value of indexing and search features in a video platform for education. This paper reports on the development and evaluation of ICS videos framework and over 5 years of usage experience in several STEM courses.

  19. Simple video format for mobile applications

    Science.gov (United States)

    Smith, John R.; Miao, Zhourong; Li, Chung-Sheng

    2000-04-01

    With the advent of pervasive computing, there is a growing demand for enabling multimedia applications on mobile devices. Large numbers of pervasive computing devices, such as personal digital assistants (PDAs), hand-held computer (HHC), smart phones, portable audio players, automotive computing devices, and wearable computers are gaining access to online information sources. However, the pervasive computing devices are often constrained along a number of dimensions, such as processing power, local storage, display size and depth, connectivity, and communication bandwidth, which makes it difficult to access rich image and video content. In this paper, we report on our initial efforts in designing a simple scalable video format with low-decoding and transcoding complexity for pervasive computing. The goal is to enable image and video access for mobile applications such as electronic catalog shopping, video conferencing, remote surveillance and video mail using pervasive computing devices.

  20. Semantic annotation for live and posterity logging of video documents

    Science.gov (United States)

    Bertini, Marco; Del Bimbo, Alberto; Nunziati, W.

    2003-06-01

    Broadcasters usually envision two basic applications for video databases: Live Logging and Posterity Logging. The former aims at providing effective annotation of video in quasi-real time and supports extraction of meaningful clips from the live stream; it is usually performed by assistant producers working at the same location of the event. The latter provides annotation for later reuse of video material and is the prerequisite for retrieval by content from video digital libraries; it is performed by trained librarians. Both require that annotation is performed, at a great extent, automatically. Video information structure must encompass both low-intermediate level video organization and event relationships that define specific highlights and situations. Analysis of the visual data of the video stream permits to extract hints, identify events and detect highlights. All of this must be supported by a-priori knowledge of the video domain and effective reasoning engines capable to capture the inherent semantics of the visual events.

  1. VLSI Neural Networks Help To Compress Video Signals

    Science.gov (United States)

    Fang, Wai-Chi; Sheu, Bing J.

    1996-01-01

    Advanced analog/digital electronic system for compression of video signals incorporates artificial neural networks. Performs motion-estimation and image-data-compression processing. Effectively eliminates temporal and spatial redundancies of sequences of video images; processes video image data, retaining only nonredundant parts to be transmitted, then transmits resulting data stream in form of efficient code. Reduces bandwidth and storage requirements for transmission and recording of video signal.

  2. The Relationships Between the Center of Mass Position and the Trunk, Hip, and Knee Kinematics in the Sagittal Plane: A Pilot Study on Field-Based Video Analysis for Female Soccer Players

    Directory of Open Access Journals (Sweden)

    Sasaki Shogo

    2015-03-01

    Full Text Available Athletes with non-contact anterior cruciate ligament tears have common features in the sagittal plane; namely, the body’s center of mass (COM is located posterior to the base of support, the trunk and knee joints are extended, and the hip angle is flexed. However, the relationships among these variables have not been assessed in field-based movements. This study sought to determine relationships between distances from the COM to the base of support and the trunk, hip, and knee positions in women while playing soccer. Sixty events (29 single-leg landing and 31 single-leg stopping events were analyzed using two-dimensional video analysis. The relationships among the measurement variables were determined using the Pearson’s product-moment correlation coefficient, and stepwise multiple linear regression models were used to explore the relationships between the COM position and the kinematic variables. The distance from the COM to the base of support displayed a moderate negative relationship with the trunk angle (r = - 0.623, p < .0001, r2 = 0.388 and a strong positive relationship with the limb angle (r = 0.869, p < .0001, r2 = 0.755. The limb, knee, and trunk angles were selected in the best regression model (adjusted r2 = 0.953, p < .0001, f2 = 20.277. These findings suggest that an increased trunk angle and a decreased limb angle at initial contact are associated with a safer COM position. Neuromuscular training may be useful for controlling the trunk and lower limb positions during dynamic activities.

  3. Video incident analysis of concussions in boys' high school lacrosse.

    Science.gov (United States)

    Lincoln, Andrew E; Caswell, Shane V; Almquist, Jon L; Dunn, Reginald E; Hinton, Richard Y

    2013-04-01

    Boys' lacrosse has one of the highest rates of concussion among boys' high school sports. A thorough understanding of injury mechanisms and game situations associated with concussions in boys' high school lacrosse is necessary to target injury prevention efforts. To characterize common game-play scenarios and mechanisms of injury associated with concussions in boys' high school lacrosse using game video. Descriptive epidemiological study. In 25 public high schools of a single school system, 518 boys' lacrosse games were videotaped by trained videographers during the 2008 and 2009 seasons. Video of concussion incidents was examined to identify game characteristics and injury mechanisms using a lacrosse-specific coding instrument. A total of 34 concussions were captured on video. All concussions resulted from player-to-player bodily contact. Players were most often injured when contact was unanticipated or players were defenseless (n = 19; 56%), attempting to pick up a loose ball (n = 16; 47%), and/or ball handling (n = 14; 41%). Most frequently, the striking player's head (n = 27; 79%) was involved in the collision, and the struck player's head was the initial point of impact in 20 incidents (59%). In 68% (n = 23) of cases, a subsequent impact with the playing surface occurred immediately after the initial impact. A penalty was called in 26% (n = 9) of collisions. Player-to-player contact was the mechanism for all concussions. Most commonly, injured players were unaware of the pending contact, and the striking player used his head to initiate contact. Further investigation of preventive measures such as education of coaches and officials and enforcement of rules designed to prevent intentional head-to-head contact is warranted to reduce the incidence of concussions in boys' lacrosse.

  4. Serious Video Games for Health: How Behavioral Science Guided the Development of a Serious Video Game

    Science.gov (United States)

    Thompson, Debbe; Baranowski, Tom; Buday, Richard; Baranowski, Janice; Thompson, Victoria; Jago, Russell; Griffith, Melissa Juliano

    2010-01-01

    Serious video games for health are designed to entertain players while attempting to modify some aspect of their health behavior. Behavior is a complex process influenced by multiple factors, often making it difficult to change. Behavioral science provides insight into factors that influence specific actions that can be used to guide key game…

  5. Serious Video Games for Health: How Behavioral Science Guided the Development of a Serious Video Game

    Science.gov (United States)

    Thompson, Debbe; Baranowski, Tom; Buday, Richard; Baranowski, Janice; Thompson, Victoria; Jago, Russell; Griffith, Melissa Juliano

    2010-01-01

    Serious video games for health are designed to entertain players while attempting to modify some aspect of their health behavior. Behavior is a complex process influenced by multiple factors, often making it difficult to change. Behavioral science provides insight into factors that influence specific actions that can be used to guide key game…

  6. Serious video games for health: How behavioral science guided the development of a serious video game

    Science.gov (United States)

    Serious video games for health are designed to entertain players while attempting to modify some aspect of their health behavior. Behavior is a complex process influenced by multiple factors, often making it difficult to change. Behavioral science provides insight into factors that influence specifi...

  7. Streaming Media Seminar--Effective Development and Distribution of Streaming Multimedia in Education

    Science.gov (United States)

    Mainhart, Robert; Gerraughty, James; Anderson, Kristine M.

    2004-01-01

    Concisely defined, "streaming media" is moving video and/or audio transmitted over the Internet for immediate viewing/listening by an end user. However, at Saint Francis University's Center of Excellence for Remote and Medically Under-Served Areas (CERMUSA), streaming media is approached from a broader perspective. The working definition includes…

  8. MOVING PERSON IDENTIFICATION IN VIDEO SURVEILLANCE SYSTEMS

    Directory of Open Access Journals (Sweden)

    A. Y. Solomatin

    2014-07-01

    Full Text Available The paper deals with an approach for a moving person identifying in video surveillance systems. The proposed solution consists of two successive stages. Selecting of a moving human from all other moving objects in a video stream takes place at the first stage. Human identification based on facial image takes place at the second stage. Detection of a human’s movement is performed via representation of the original video stream in a form of time series. Mathematical apparatus of a singular spectrum is applied for that purpose. The presence of motion is determined by analyzing the periodic components of time series constructed from color and brightness data of the original components of initial video stream. Identification of a person based on his facial image is done through representation of a facial image via two-dimensional matrix with the subsequent application of immune computing mathematical apparatus. Then the binding energy is calculated which shows similarity between the input facial image and faces stored in the training set. The proposed solution for a problem of a moving person’s identifying gives the opportunity to work with low quality video stream having a high level of noise or compression artifacts after encoding. The advantage of the method is implementation simplicity. Unlike traditional methods of computer vision, the proposed method does not require significant computational burden due to simple numerical operations. This method does not require pre-filtering of video images, therefore its performance speed is significantly increased.

  9. A Multi-User Game-Theoretical Multipath Routing Protocol to Send Video-Warning Messages over Mobile Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Ahmad Mohamad Mezher

    2015-04-01

    Full Text Available The prevention of accidents is one of the most important goals of ad hoc networks in smart cities. When an accident happens, dynamic sensors (e.g., citizens with smart phones or tablets, smart vehicles and buses, etc. could shoot a video clip of the accident and send it through the ad hoc network. With a video message, the level of seriousness of the accident could be much better evaluated by the authorities (e.g., health care units, police and ambulance drivers rather than with just a simple text message. Besides, other citizens would be rapidly aware of the incident. In this way, smart dynamic sensors could participate in reporting a situation in the city using the ad hoc network so it would be possible to have a quick reaction warning citizens and emergency units. The deployment of an efficient routing protocol to manage video-warning messages in mobile Ad hoc Networks (MANETs has important benefits by allowing a fast warning of the incident, which potentially can save lives. To contribute with this goal, we propose a multipath routing protocol to provide video-warning messages in MANETs using a novel game-theoretical approach. As a base for our work, we start from our previous work, where a 2-players game-theoretical routing protocol was proposed to provide video-streaming services over MANETs. In this article, we further generalize the analysis made for a general number of N players in the MANET. Simulations have been carried out to show the benefits of our proposal, taking into account the mobility of the nodes and the presence of interfering traffic. Finally, we also have tested our approach in a vehicular ad hoc network as an incipient start point to develop a novel proposal specifically designed for VANETs.

  10. A Multi-User Game-Theoretical Multipath Routing Protocol to Send Video-Warning Messages over Mobile Ad Hoc Networks.

    Science.gov (United States)

    Mezher, Ahmad Mohamad; Igartua, Mónica Aguilar; de la Cruz Llopis, Luis J; Pallarès Segarra, Esteve; Tripp-Barba, Carolina; Urquiza-Aguiar, Luis; Forné, Jordi; Sanvicente Gargallo, Emilio

    2015-04-17

    The prevention of accidents is one of the most important goals of ad hoc networks in smart cities. When an accident happens, dynamic sensors (e.g., citizens with smart phones or tablets, smart vehicles and buses, etc.) could shoot a video clip of the accident and send it through the ad hoc network. With a video message, the level of seriousness of the accident could be much better evaluated by the authorities (e.g., health care units, police and ambulance drivers) rather than with just a simple text message. Besides, other citizens would be rapidly aware of the incident. In this way, smart dynamic sensors could participate in reporting a situation in the city using the ad hoc network so it would be possible to have a quick reaction warning citizens and emergency units. The deployment of an efficient routing protocol to manage video-warning messages in mobile Ad hoc Networks (MANETs) has important benefits by allowing a fast warning of the incident, which potentially can save lives. To contribute with this goal, we propose a multipath routing protocol to provide video-warning messages in MANETs using a novel game-theoretical approach. As a base for our work, we start from our previous work, where a 2-players game-theoretical routing protocol was proposed to provide video-streaming services over MANETs. In this article, we further generalize the analysis made for a general number of N players in the MANET. Simulations have been carried out to show the benefits of our proposal, taking into account the mobility of the nodes and the presence of interfering traffic. Finally, we also have tested our approach in a vehicular ad hoc network as an incipient start point to develop a novel proposal specifically designed for VANETs.

  11. An Overview of Structural Characteristics in Problematic Video Game Playing.

    Science.gov (United States)

    Griffiths, Mark D; Nuyens, Filip

    2017-01-01

    There are many different factors involved in how and why people develop problems with video game playing. One such set of factors concerns the structural characteristics of video games (i.e., the structure, elements, and components of the video games themselves). Much of the research examining the structural characteristics of video games was initially based on research and theorizing from the gambling studies field. The present review briefly overviews the key papers in the field to date. The paper examines a number of areas including (i) similarities in structural characteristics of gambling and video gaming, (ii) structural characteristics in video games, (iii) narrative and flow in video games, (iv) structural characteristic taxonomies for video games, and (v) video game structural characteristics and game design ethics. Many of the studies carried out to date are small-scale, and comprise self-selected convenience samples (typically using self-report surveys or non-ecologically valid laboratory experiments). Based on the small amount of empirical data, it appears that structural features that take a long time to achieve in-game are the ones most associated with problematic video game play (e.g., earning experience points, managing in-game resources, mastering the video game, getting 100% in-game). The study of video games from a structural characteristic perspective is of benefit to many different stakeholders including academic researchers, video game players, and video game designers, as well as those interested in prevention and policymaking by making the games more socially responsible. It is important that researchers understand and recognize the psycho-social effects and impacts that the structural characteristics of video games can have on players, both positive and negative.

  12. A Caching Strategy for Streaming Media

    Institute of Scientific and Technical Information of China (English)

    谭劲; 余胜生; 周敬利

    2004-01-01

    It is expected that by 2003 continuous media will account for more than 50% of the data available on origin servers, this will provoke a significant change in Internet workload. Due to the high bandwidth requirements and the long-lived nature of digital video, streaming server loads and network bandwidths are proven to be major limiting factors. Aiming at the characteristics of broadband network in residential areas, this paper proposes a popularity-based server-proxy caching strategy for streaming media. According to a streaming media popularity on streaming server and proxy, this strategy caches the content of the streaming media partially or completely. The paper also proposes two formulas that calculate the popularity coefficient of a streaming media on server and proxy, and caching replacement policy. As expected, this strategy decreases the server load, reduces the traffic from streaming server to proxy, and improves client start-up latency.

  13. THE CASE AGAINST LEARNING IN SCHOOL WITH EVIDENCE FROM VIDEO GAME STUDIES

    National Research Council Canada - National Science Library

    Izabela USCINSKI

    2013-01-01

    .... Then, she demonstrates that learning principles built into the video games as proposed by James Gee, are more effective in engaging players in skills needed in the 21st century than many activities...

  14. The narrative impact of active video games on physical activity among children: A feasibility study

    Science.gov (United States)

    Active video games (AVGs) capable of inducing physical activity offer an innovative approach to combating childhood obesity. Unfortunately, children's AVG game play decreases quickly, underscoring the need to identify novel methods for player engagement. Narratives have been demonstrated to influenc...

  15. Non-Cooperative Facial Recognition Video Dataset Collection Plan

    Energy Technology Data Exchange (ETDEWEB)

    Kimura, Marcia L.; Erikson, Rebecca L.; Lombardo, Nicholas J.

    2013-08-31

    The Pacific Northwest National Laboratory (PNNL) will produce a non-cooperative (i.e. not posing for the camera) facial recognition video data set for research purposes to evaluate and enhance facial recognition systems technology. The aggregate data set consists of 1) videos capturing PNNL role players and public volunteers in three key operational settings, 2) photographs of the role players for enrolling in an evaluation database, and 3) ground truth data that documents when the role player is within various camera fields of view. PNNL will deliver the aggregate data set to DHS who may then choose to make it available to other government agencies interested in evaluating and enhancing facial recognition systems. The three operational settings that will be the focus of the video collection effort include: 1) unidirectional crowd flow 2) bi-directional crowd flow, and 3) linear and/or serpentine queues.

  16. Low Complexity for Scalable Video Coding Extension of H.264 based on the Complexity of Video

    Directory of Open Access Journals (Sweden)

    Mayada Khairy

    2016-12-01

    Full Text Available Scalable Video Coding (SVC / H.264 is one type of video compression techniques. Which provided more reality in dealing with video compression to provide an efficient video coding based on H.264/AVC. This ensures higher performance through high compression ratio. SVC/H.264 is a complexity technique whereas the takes considerable time for computation the best mode of macroblock and motion estimation through using the exhaustive search techniques. This work reducing the processing time through matching between the complexity of the video and the method of selection macroblock and motion estimation. The goal of this approach is reducing the encoding time and improving the quality of video stream the efficiency of the proposed approach makes it suitable for are many applications as video conference application and security application.

  17. Implementation and Analysis of Real-Time Streaming Protocols.

    Science.gov (United States)

    Santos-González, Iván; Rivero-García, Alexandra; Molina-Gil, Jezabel; Caballero-Gil, Pino

    2017-04-12

    Communication media have become the primary way of interaction thanks to the discovery and innovation of many new technologies. One of the most widely used communication systems today is video streaming, which is constantly evolving. Such communications are a good alternative to face-to-face meetings, and are therefore very useful for coping with many problems caused by distance. However, they suffer from different issues such as bandwidth limitation, network congestion, energy efficiency, cost, reliability and connectivity. Hence, the quality of service and the quality of experience are considered the two most important issues for this type of communication. This work presents a complete comparative study of two of the most used protocols of video streaming, Real Time Streaming Protocol (RTSP) and the Web Real-Time Communication (WebRTC). In addition, this paper proposes two new mobile applications that implement those protocols in Android whose objective is to know how they are influenced by the aspects that most affect the streaming quality of service, which are the connection establishment time and the stream reception time. The new video streaming applications are also compared with the most popular video streaming applications for Android, and the experimental results of the analysis show that the developed WebRTC implementation improves the performance of the most popular video streaming applications with respect to the stream packet delay.

  18. Providing VoD Streaming Using P2P Networks

    Science.gov (United States)

    Pedro Muñoz-Gea, Juan; Malgosa-Sanahuja, Josemaria; Manzanares-Lopez, Pilar; Carlos Sanchez-Aarnoutse, Juan

    Overlays and P2P systems, initially developed to support IP multicast and file-sharing, have moved beyond that functionality. They are also proving to be key technologies for the delivery of video streaming. Recently, there have been a number of successful deployments for "live" P2P streaming. However, the question remains open whether similar P2P technologies can be used to provide VoD (Video-On-Demand) services. A P2P VoD service is more challenging to design than a P2P live streaming system because the system should allow users arriving at arbitrary times to watch (arbitrary parts of) the video.

  19. VLSI-based Video Event Triggering for Image Data Compression

    Science.gov (United States)

    Williams, Glenn L.

    1994-01-01

    Long-duration, on-orbit microgravity experiments require a combination of high resolution and high frame rate video data acquisition. The digitized high-rate video stream presents a difficult data storage problem. Data produced at rates of several hundred million bytes per second may require a total mission video data storage requirement exceeding one terabyte. A NASA-designed, VLSI-based, highly parallel digital state machine generates a digital trigger signal at the onset of a video event. High capacity random access memory storage coupled with newly available fuzzy logic devices permits the monitoring of a video image stream for long term (DC-like) or short term (AC-like) changes caused by spatial translation, dilation, appearance, disappearance, or color change in a video object. Pre-trigger and post-trigger storage techniques are then adaptable to archiving only the significant video images.

  20. Using Video Modeling Delivered through iPods to Teach Vocational Tasks to Young Adults with Autism Spectrum Disorders (ASD)

    Science.gov (United States)

    Kellems, Ryan O.

    2010-01-01

    The purpose of this study was to evaluate the effectiveness of using video modeling delivered through a Portable media player (video iPod) as a means of teaching three job-related tasks to four young adults with autism spectrum disorders (ASD) in a community-based employment setting. The videos used in the study were enhanced by adding written…

  1. Comparison of game addiction prevalence rates between MMOFPS players and MMORPG players. A case of EVE Online and DUST 514

    OpenAIRE

    Guðmundur Helgason 1990; Ólafur Hrafn Steinarsson 1990

    2013-01-01

    The main aim of this research project was to explore the prevalence of gaming addiction among players of different genres of video games. Additionally, the potential risks of structural characteristics of games were also examined. The sample consisted of 445 participants, aged 13 to 67, with 96.6% being male and 3.4% being female. To assess video game addiction the short version of the GAS-7 (Lemmens et al., 2009) was employed. The results showed that no significant differences were found bet...

  2. Data Partitioning Technique for Improved Video Prioritization

    Directory of Open Access Journals (Sweden)

    Ismail Amin Ali

    2017-07-01

    Full Text Available A compressed video bitstream can be partitioned according to the coding priority of the data, allowing prioritized wireless communication or selective dropping in a congested channel. Known as data partitioning in the H.264/Advanced Video Coding (AVC codec, this paper introduces a further sub-partition of one of the H.264/AVC codec’s three data-partitions. Results show a 5 dB improvement in Peak Signal-to-Noise Ratio (PSNR through this innovation. In particular, the data partition containing intra-coded residuals is sub-divided into data from: those macroblocks (MBs naturally intra-coded, and those MBs forcibly inserted for non-periodic intra-refresh. Interactive user-to-user video streaming can benefit, as then HTTP adaptive streaming is inappropriate and the High Efficiency Video Coding (HEVC codec is too energy demanding.

  3. THE EDUCATIONAL POTENTIAL OF VIDEO GAMES

    Directory of Open Access Journals (Sweden)

    Ruxandra Claudia CHIRCA (NEACȘU

    2015-11-01

    Full Text Available In nowadays' world, technological assistance is no longer confined to its primary purpose of communication or informational support and the boundaries between real and virtual world are becoming increasingly harder to be defined. This is the world of digital natives, today's children, who grow up in a technology-brimming environment and who spend most of their time playing video games. Are these video games constructive in any way? Scientific studies state they are. Video games help children in setting their goals, provide constant feedback and offer immediate rewards, along with the opportunity to collaborate with other players. Furthermore, video games can generate strong emotional reactions, such as joy or fear, and they have a captivating story line, which reveals itself within a realm of elaborate graphics.

  4. Digital Video taken during the 3-person submersible Clelia dive 608 of the NOAA Office of Ocean Exploration's Islands in the Stream 2001 cruise, August 30, 2001 (NCEI Accession 0039353)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Islands in the Stream is a three-month scientific expedition to marine protected areas and other habitats being considered for protection from offshore of Belize in...

  5. Digital Video taken during the 3-person submersible Clelia dive 607 of the NOAA Office of Ocean Exploration's Islands in the Stream 2001 cruise, August 29, 2001 (NCEI Accession 0039467)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Islands in the Stream is a three-month scientific expedition to marine protected areas and other habitats being considered for protection from offshore of Belize in...

  6. A Hybrid-Streaming Method for Cloud Gaming: To Improve the Graphics Quality delivered on Highly Accessible Game Contents

    Directory of Open Access Journals (Sweden)

    Kar Long Chan

    2017-06-01

    Full Text Available The emerging Cloud Gaming Service provides a highly accessible video gaming experience. With Cloud Gaming, potential players without enough local resource can access high-quality gaming using low-spec devices. With advancing technology, we consider that if the processing power at low-spec devices can be well harvested, the quality delivered on Cloud Gaming can be further improved. Therefore, we propose a Hybrid-Streaming System that aimed at improving the graphic quality delivered by Cloud Gaming. By utilizing the available rendering power from both the Cloud Server and client PC, the system distributes rendering operations to both sides to achieve the desired improvement. Quantitative results show the proposed method improves graphics quality, as well as reducing the server’s workload while attaining acceptable network bandwidth consumption levels.

  7. How should "hot" players in basketball be defended? The use of fast-and-frugal heuristics by basketball coaches and players in response to streakiness.

    Science.gov (United States)

    Csapo, Peter; Avugos, Simcha; Raab, Markus; Bar-Eli, Michael

    2015-01-01

    Previous research has shown that changes in shot difficulty may have rendered the hot-hand effect in basketball unobservable and are potentially a result of defensive adjustments. However, it has not been directly analysed whether strategic changes indeed take place in response to streakiness and whether they are effective with respect to winning games. The current work consists of an experimental study with 18 professional coaches and 20 players based on video sequences from National Basketball Association games, where the shown player displayed a streaky performance in half of the sequences. While coaches were asked to devise a defensive strategy after each viewed sequence, players had to assume the role of the shown player and decide whether to shoot or pass the ball. We find that coaches tended to increase the defensive pressure significantly more often on presumably hot players and thus make use of the hot-hand heuristic. Meanwhile, players chose to shoot more frequently in low-pressure and streaky situations but selected "pass" regardless of the previous performance when they faced increased defensive pressure. Assuming that a streaky player's performance is indeed elevated during hot phases, hot-hand behaviour can be considered adaptive in certain situations as it led hot players to pass instead of shoot.

  8. EI Videos

    CERN Document Server

    Courtney, Michael; Courtney, Amy

    2012-01-01

    The Quantitative Reasoning Center (QRC) at USAFA has the institution's primary responsibility for offering after hours extra instruction (EI) in core technical disciplines (mathematics, chemistry, physics, and engineering mechanics). Demand has been tremendous, totaling over 3600 evening EI sessions in the Fall of 2010. Meeting this demand with only four (now five) full time faculty has been challenging. EI Videos have been produced to help serve cadets in need of well-modeled solutions to homework-type problems. These videos have been warmly received, being viewed over 14,000 times in Fall 2010 and probably contributing to a significant increase in the first attempt success rate on the Algebra Fundamental Skills Exam in Calculus 1. EI Video production is being extended to better support Calculus 2, Calculus 3, and Physics 1.

  9. Video doorphone

    OpenAIRE

    Horyna, Miroslav

    2015-01-01

    Tato diplomová práce se zabývá návrhem dveřního video telefonu na platformě Raspberry Pi. Je zde popsána platforma Raspberry Pi, modul Raspberry Pi Camera, operační systémy pro Raspberry Pi a popis instalace a nastavení softwaru. Dále je zde popsán návrh a popis programů vytvořených pro dveřní video telefon a návrh přídavných modulů. This thesis deals with door video phone on the platform Raspberry Pi. There is described the platform Raspberry Pi, Raspberry Pi Camera module, operating syst...

  10. Video Podcasts

    DEFF Research Database (Denmark)

    Nortvig, Anne Mette; Sørensen, Birgitte Holm

    2016-01-01

    This project’s aim was to support and facilitate master’s students’ preparation and collaboration by making video podcasts of short lectures available on YouTube prior to students’ first face-to-face seminar. The empirical material stems from group interviews, from statistical data created through...... YouTube analytics and from surveys answered by students after the seminar. The project sought to explore how video podcasts support learning and reflection online and how students use and reflect on the integration of online activities in the videos. Findings showed that students engaged actively...... in podcasts that included designed activities, and moreover – although to a lesser degree – that students engaged actively in podcasts that did not include additional activities, suggesting that learning via podcast does not always mean learning by passive listening....

  11. Stream Evaluation

    Data.gov (United States)

    Kansas Data Access and Support Center — Digital representation of the map accompanying the "Kansas stream and river fishery resource evaluation" (R.E. Moss and K. Brunson, 1981.U.S. Fish and Wildlife...

  12. Stream Lab

    OpenAIRE

    Kummel, Miro; Bruder, Andrea; Powell, Jim; Kohler, Brynja; Lewis, Matt

    2016-01-01

    Dead leaves, ping-pong balls or plastic golf balls are floated down a small stream. The number of leaves/balls passing recording stations along the stream are tallied. Students are then challenged to develop a transport model for the resulting data. From this exercise students gain greater understanding of PDE modeling, conservation laws, parameter estimation as well as mass and momentum transport processes.

  13. A Simple Exercise-to-Play Proposal that would Reduce Games Addiction and Keep Players Healthy

    Directory of Open Access Journals (Sweden)

    Nael Hirzallah

    2013-03-01

    Full Text Available Games players usually get addicted to video games in general and more specifically to those that are usually played over the internet. These players prefer to stay at home and play games rather than playing sports or outdoor games. This paper presents a proposal that aims to implement a simple way to let video games players exercise in order to play. The proposal targets games where players virtually live inside a certain area such as a forest, city or a war zone. Their aim is to explore the area, capture, kill and avoid being killed by something or someone. A costumed built treadmill acting as a movement capture device is proposed to capture players’ commands for movements. These movements include Running, walking, Stopping, and Turning. In that way, the players enjoy exercising as well as playing the game. However, sooner or later, the players get exhausted driving them to exit the game. That way, we believe that such a proposal would keep players healthy, and reduce the chance of addiction.

  14. Context-dependent player's movement interpretation: application to adaptive game development

    Science.gov (United States)

    Picard, Francois; Estraillier, Pascal

    2010-02-01

    Video games are more and more controlled by the real movements of the player. However, the player is constrained by the system devices, imposing a limited vocabulary of actions associated with a set of unnatural movements. To introduce more entertaining video games to players, a component-based architecture is proposed. It has been acknowledged as the starting point for the development of adaptive applications based on the hypothesis of a high level dialogue between the system and the player. The system adaptability relies on interpretation mechanisms of the player behaviors. These behaviors are defined through the representation of the real movements of the player who freely interacts with the 3D elements composing an immersive virtual environment, following a given game scenario. The efficient interpretation of the player movements relies on the introduction in the system of the management of the scene's context. The contextual information not only helps to determine the true meaning of an observed behavior but also makes the system to adapt its processes regarding this interpretation, while managing its hardware and software resources efficiently. A commercial motion capture interface has been enhanced by the elaboration of such a system.

  15. Classification-based Multi-client Video Transmission over Heterogeneous Networks

    Directory of Open Access Journals (Sweden)

    Bo Li

    2013-08-01

    Full Text Available These Real-time video streaming over networks operates under stringent network resource constraints, with multiple video clients competing for limited network resources. In this paper, we study the problem of bandwidth allocation for video transmission over heterogeneous networks, with multiple video clients connecting to the video server simultaneously and demanding for the video services, and aim to provide the best possible Quality of Service (QoS under limited bandwidth of both the video server and multiple video clients. We propose a classification-based approach for multi-client video transmission over heterogeneous networks (CMVT. Firstly, the video server detects the available bandwidth of multiple video clients and classifies the clients into different classes. Secondly, the limited export bandwidth of the server is allocated to different video clients using the client classification results and greedy algorithm. Finally, the video server transmits video streams to video clients in different classes through Unicast and clients in the same class through Unicast and forwarding. Experimental results demonstrate that the proposed video transmission method can use the network bandwidth efficiently and provide better video quality to more video clients

  16. THE VIDEO GAMER’S DILEMMA: ENTERTAINMENT VERSUS MORALITY

    Directory of Open Access Journals (Sweden)

    Dr. Sony Jalarajan Raj

    2014-01-01

    Full Text Available Video games today are not just an electronic extension of playing favourite games. Now it is emerged as one of mainstream mass medium and an industry worth billions. Video games and its popularity grew around the sphere regardless demographic and geographic taxonomy. Began in late 1940s, with platform of cathode ray tube television sets and specially equipped platforms are now available on mobile phones and other portable gadget with easy mobility and more live three dimensional views. The video games use user interaction and visual feedback which exercise much mental and physical attention of player. This in fact leads to develop application in day to day life of players. Video games have become a widely popular and highly profitable medium of entertainment. Animated characters with motion and multidimensionality are not only affecting the cognitive of a human but also to the tender feelings and emotions..

  17. Effects of playing video games on perceptions of one's humanity.

    Science.gov (United States)

    Greitemeyer, Tobias

    2013-01-01

    According to self-perception theory, individuals infer their characteristics by observing their own behavior. In the present research, the hypothesis is examined whether helping behavior increases perceptions of one's own humanity even when help is given that does not benefit a real person. In fact, two studies revealed that playing a prosocial video game (where the goal is to help and care for other game characters) led to increased perceptions of the player's own humanity (in particular, for positive humanity traits). Results also revealed that playing a violent, relative to a neutral, video game decreased perceptions of humanity on positive humanity traits and increased perceptions of humanity on negative humanity traits. Taken together, it appears that being helpful while playing video games leads to the perception of being more human, whereas being harmful while playing video games leads players to perceive themselves negatively.

  18. Quantifying the high-speed running and sprinting profiles of elite female soccer players during competitive matches using an Optical Player Tracking System.

    Science.gov (United States)

    Mara, Jocelyn K; Thompson, Kevin G; Pumpa, Kate L; Morgan, Stuart

    2016-09-06

    The aim of this study was to determine the high-speed running and sprinting profiles of elite female soccer players during competitive matches using a new Optical Player Tracking System. Eight stationary video cameras were positioned at vantage points surrounding the soccer field so that when each camera view was combined the entire field could be viewed simultaneously. Following each match, an optical player tracking system detected the coordinates (x,y) of each player for every video frame. Algorithms applied to the x and y coordinates were used to determine activity variables for twelve elite female players across seven competitive matches. Players covered 9,220-10,581 m of total distance, 1,772-2,917 m of high-speed running (3.4-5.3 m·s) distance and 417-850 m of sprinting (>5.4 m·s) distance, with variations between positional groups (p sprints (71-78 %) were performed over distances less than 10 m. Mean time between high-speed runs (13.9 s ± 4.4) and sprints (86.5 s ± 38.0) varied according to playing position (p drills, and shows that coaches should take an individualised approach to training load monitoring according to position.

  19. Akademisk video

    DEFF Research Database (Denmark)

    Frølunde, Lisbeth

    2016-01-01

    Dette kapitel har fokus på metodiske og systemiske problemstillinger vedrørende forskerens positionering i forhold til at formidle på digitale medier, særligt med video. De systemiske problemer omfatter en Janus dobbelthed; forskeren vil måske gerne formidle på digitale platforme, men er tynget...... indadtil af ansvar, tidspres, renomé, kvalitetskrav, og digitale platformes flygtighed. De metodiske problemer inkluderer at videoanalyse trækker på mange traditioner, men er underudviklet i forhold til den digitale kontekst. Empirien består af eksempler på online formidling i form af “akademisk video......”. Analysen anvender narrativ, multimodal analyse af video, primært to videoer på platformen audiovisualthinking.org, hvor forskeren optræder som fortæller eller “storyteller”. En video er lavet af forfatteren. Videoanalysen er valideret gennem kollaboration med en af audiovisualthinking.org stifterne. De...

  20. Active Learning for Player Modeling

    DEFF Research Database (Denmark)

    Shaker, Noor; Abou-Zleikha, Mohamed; Shaker, Mohammad

    2015-01-01

    Learning models of player behavior has been the focus of several studies. This work is motivated by better understanding of player behavior, a knowledge that can ultimately be employed to provide player-adapted or personalized content. In this paper, we propose the use of active learning for player...... experience modeling. We use a dataset from hundreds of players playing Infinite Mario Bros. as a case study and we employ the random forest method to learn mod- els of player experience through the active learning approach. The results obtained suggest that only part of the dataset (up to half the size...... of the full dataset) is necessary for the construction of accu- rate models that are as accurate as those constructed from the full dataset. This indicates the potential of the method and its benefits in cases when obtaining the data is expensive or time, storage or effort consuming. The results also indicate...

  1. Active Learning for Player Modeling

    DEFF Research Database (Denmark)

    Shaker, Noor; Abou-Zleikha, Mohamed; Shaker, Mohammad

    2015-01-01

    Learning models of player behavior has been the focus of several studies. This work is motivated by better understanding of player behavior, a knowledge that can ultimately be employed to provide player-adapted or personalized content. In this paper, we propose the use of active learning for player...... experience modeling. We use a dataset from hundreds of players playing Infinite Mario Bros. as a case study and we employ the random forest method to learn mod- els of player experience through the active learning approach. The results obtained suggest that only part of the dataset (up to half the size...... of the full dataset) is necessary for the construction of accu- rate models that are as accurate as those constructed from the full dataset. This indicates the potential of the method and its benefits in cases when obtaining the data is expensive or time, storage or effort consuming. The results also indicate...

  2. Teaching introductory undergraduate Physics using commercial video games

    CERN Document Server

    Mohanty, Soumya D

    2011-01-01

    Commercial video games are increasingly using sophisticated physics simulations to create a more immersive experience for players. This also makes them a powerful tool for engaging students in learning physics. We provide some examples to show how commercial off-the-shelf games can be used to teach specific topics in introductory undergraduate physics. The examples are selected from a course taught predominantly through the medium of commercial video games.

  3. Scalable video on demand adaptive Internet-based distribution

    CERN Document Server

    Zink, Michael

    2013-01-01

    In recent years, the proliferation of available video content and the popularity of the Internet have encouraged service providers to develop new ways of distributing content to clients. Increasing video scaling ratios and advanced digital signal processing techniques have led to Internet Video-on-Demand applications, but these currently lack efficiency and quality. Scalable Video on Demand: Adaptive Internet-based Distribution examines how current video compression and streaming can be used to deliver high-quality applications over the Internet. In addition to analysing the problems

  4. Topology Dictionary for 3D Video Understanding

    OpenAIRE

    2012-01-01

    This paper presents a novel approach that achieves 3D video understanding. 3D video consists of a stream of 3D models of subjects in motion. The acquisition of long sequences requires large storage space (2 GB for 1 min). Moreover, it is tedious to browse data sets and extract meaningful information. We propose the topology dictionary to encode and describe 3D video content. The model consists of a topology-based shape descriptor dictionary which can be generated from either extracted pattern...

  5. Brugeroplevelse af streaming-tjenesten Netflix

    OpenAIRE

    Leifer, Anders; Frydendahl, Erik Pouret; Nedergaard, Mads Kresten

    2014-01-01

    This paper aims to describe and understand the use of the video streaming service Netflix among younger single females, with the further aim to understand the success of streaming in general and Netflix’s offer as an experience economy based offering in particular. After introducing Netflix through a review of its history and its competitive environment, and establishing the epistemological and methodological framework, the paper presents its empiric part, a qualitative semi-structured int...

  6. Performance evaluation of MPEG internet video coding

    Science.gov (United States)

    Luo, Jiajia; Wang, Ronggang; Fan, Kui; Wang, Zhenyu; Li, Ge; Wang, Wenmin

    2016-09-01

    Internet Video Coding (IVC) has been developed in MPEG by combining well-known existing technology elements and new coding tools with royalty-free declarations. In June 2015, IVC project was approved as ISO/IEC 14496-33 (MPEG- 4 Internet Video Coding). It is believed that this standard can be highly beneficial for video services in the Internet domain. This paper evaluates the objective and subjective performances of IVC by comparing it against Web Video Coding (WVC), Video Coding for Browsers (VCB) and AVC High Profile. Experimental results show that IVC's compression performance is approximately equal to that of the AVC High Profile for typical operational settings, both for streaming and low-delay applications, and is better than WVC and VCB.

  7. An Algorithm of Extracting I-Frame in Compressed Video

    Directory of Open Access Journals (Sweden)

    Zhu Yaling

    2015-01-01

    Full Text Available The MPEG video data includes three types of frames, that is: I-frame, P-frame and B-frame. However, the I-frame records the main information of video data, the P-frame and the B-frame are just regarded as motion compensations of the I-frame. This paper presents the approach which analyzes the MPEG video stream in the compressed domain, and find out the key frame of MPEG video stream by extracting the I-frame. Experiments indicated that this method can be automatically realized in the compressed MPEG video and it will lay the foundation for the video processing in the future.

  8. Fair rate allocation of scalable multiple description video for many clients

    NARCIS (Netherlands)

    Taal, R.J.; Lagendijk, R.L.

    2005-01-01

    Peer-to-peer networks (P2P) form a distributed communication infrastructure that is particularly well matched to video streaming using multiple description coding. We form M descriptions using MDC-FEC building on a scalable version of the “Dirac” video coder. The M descriptions are streamed via M di

  9. Automatic video surveillance of outdoor scenes using track before detect

    DEFF Research Database (Denmark)

    Hansen, Morten; Sørensen, Helge Bjarup Dissing; Birkemark, Christian M.

    2005-01-01

    This paper concerns automatic video surveillance of outdoor scenes using a single camera. The first step in automatic interpretation of the video stream is activity detection based on background subtraction. Usually, this process will generate a large number of false alarms in outdoor scenes due...

  10. Playing for Real, Video Games and Stories for Health-Related Behavior Change

    Science.gov (United States)

    Video games provide extensive player involvement for large numbers of children and adults, and thereby provide a channel for delivering health behavior change experiences and messages in an engaging and entertaining format. Twenty-seven articles were identified on 25 video games that promoted health...

  11. The Racing-Game Effect : Why Do Video Racing Games Increase Risk-Taking Inclinations?

    NARCIS (Netherlands)

    Fischer, Peter; Greitemeyer, Tobias; Morton, Thomas; Kastenmueller, Andreas; Postmes, Tom; Frey, Dieter; Kubitzki, Joerg; Odenwaelder, Joerg; Kastenmüller, A.; Odenwälder, J.

    2009-01-01

    The present studies investigated why video racing games increase players' risk-taking inclinations. Four studies reveal that playing video racing games increases risk taking in a subsequent simulated road traffic situation, as well as risk-promoting cognitions and emotions, blood pressure, sensation

  12. A Gatekeeper Final Boss: An Analysis of MOGAI Representation in Video Games

    Directory of Open Access Journals (Sweden)

    Jared Talbert

    2016-07-01

    Full Text Available There have been MOGAI characters since near the beginning of video games, but their representation has been something of debate and controversy. This paper looks at not only the history of representing MOGAI characters, but the dynamics of how these populations are represented within video games, and analyses how players feel regarding this subject.

  13. The Racing-Game Effect : Why Do Video Racing Games Increase Risk-Taking Inclinations?

    NARCIS (Netherlands)

    Fischer, Peter; Greitemeyer, Tobias; Morton, Thomas; Kastenmueller, Andreas; Postmes, Tom; Frey, Dieter; Kubitzki, Joerg; Odenwaelder, Joerg; Kastenmüller, A.; Odenwälder, J.

    2009-01-01

    The present studies investigated why video racing games increase players' risk-taking inclinations. Four studies reveal that playing video racing games increases risk taking in a subsequent simulated road traffic situation, as well as risk-promoting cognitions and emotions, blood pressure, sensation

  14. The Effect of Digital Video Games on EFL Students' Language Learning Motivation

    Science.gov (United States)

    Ebrahimzadeh, Mohsen; Alavi, Sepideh

    2017-01-01

    The study examined the effect of a commercial digital video game on high school students' language learning motivation. Participants were 241 male students randomly assigned to one of the following three treatments: Readers, who intensively read the game's story; Players, who played the digital video game; and Watchers, who watched two classmates…

  15. stream-stream: Stellar and dark-matter streams interactions

    Science.gov (United States)

    Bovy, Jo

    2017-02-01

    Stream-stream analyzes the interaction between a stellar stream and a disrupting dark-matter halo. It requires galpy (ascl:1411.008), NEMO (ascl:1010.051), and the usual common scientific Python packages.

  16. Predicting early adoption of successive video player generations

    NARCIS (Netherlands)

    Rijnsoever, F.J. van; Oppewal, H.

    2012-01-01

    Early adopters play an important role in the innovation diffusion process. Over the past decades, many factors have been identified as predictors for earlyadoption of innovations. Less attention has been paid to the relationship between the earlyadoption of one generation of a specific product and

  17. Predicting early adoption of successive video player generations

    NARCIS (Netherlands)

    Rijnsoever, F.J. van; Oppewal, H.

    2012-01-01

    Early adopters play an important role in the innovation diffusion process. Over the past decades, many factors have been identified as predictors for earlyadoption of innovations. Less attention has been paid to the relationship between the earlyadoption of one generation of a specific product and t

  18. Violent Video Games May Not 'Desensitize' Players, Brain Scans Suggest

    Science.gov (United States)

    ... Department of Psychiatry at Hannover Medical School in Germany. Szycik acknowledged that the study doesn't say ... nat., lecturer, Department of Psychiatry, Hannover Medical School, Germany; Christopher Ferguson, Ph.D., professor, psychology, Stetson University, ...

  19. Video quality based link adaptation for low latency video transmission over WLANs

    Institute of Scientific and Technical Information of China (English)

    FERR(E) Pierre; DOUFEXI Angela; CHUNG-HOW James; NIX Andrew; BULL David

    2006-01-01

    Wireless Local Area Networks (WLANs) such as IEEE 802.11a/g and Hiperlan/2 utilise numerous transmission modes,each providing different throughputs and reliability levels. Many link adaptation algorithms proposed in the literature either maximise the error-free data throughput based on channel conditions or are based on the number of failed transmissions. However, these algorithms do not take into account the content of the data stream and strongly rely on the use of Automatic Repeat Requests (ARQs). Low latency video applications such as real-time video transmission may require no retransmission, or only a limited number of retransmissions. Moreover, completely error-free communication is not essential, especially if robust video compression techniques are applied. In such scenarios, improved decoded video quality can be obtained with a video stream transmitted at a higher bit rate using a higher link speed but with some degree of transmission error, rather than an error-free video stream at a lower bit rate using a lower link speed. In this work, we investigate a link adaptation scheme that improves the Quality of Service (QoS) for video transmission,based on the overall received video quality (Peak Signal to Noise Ratio, PSNR), rather than by maximising the error-free throughput.We also study a practical link adaptation approach that uses PER thresholds at the PHY layer. An empirical study showed that thresholds for switching from one mode to another are much lower (almost error free) than those currently used by throughput based schemes. We show that traditional link adaptation strategies are not appropriate for real-time video transmission with no retransmission. Simulation results using the H.264 video compression standard over IEEE 802.11 a are presented.

  20. Gaming to see: Action Video Gaming is associated with enhanced processing of masked stimuli

    Directory of Open Access Journals (Sweden)

    Carsten ePohl

    2014-02-01

    Full Text Available Recent research revealed that action video game players outperform non-players in a wide range of attentional, perceptual and cognitive tasks. Here we tested if expertise in action video games is related to differences regarding the potential of shortly presented stimuli to bias behaviour. In a response priming paradigm, participants classified four animal pictures functioning as targets as being smaller or larger than a reference frame. Before each target, one of the same four animal pictures was presented as a masked prime to influence participants’ responses in a congruent or incongruent way. Masked primes induced congruence effects, that is, faster responses for congruent compared to incongruent conditions, indicating processing of hardly visible primes. Results also suggested that action video game players showed a larger congruence effect than non-players for 20 ms primes, whereas there was no group difference for 60 ms primes. In addition, there was a tendency for action video game players to detect masked primes for some prime durations better than non-players. Thus, action video game expertise may be accompanied by faster and more efficient processing of shortly presented visual stimuli.