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Topic: Video coding


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  Video compression - Wikipedia, the free encyclopedia
Video compression is necessary for efficient coding of video data in video file formats and streaming video formats.
However, in interlaced video, the set of horizontal lines with even numbers and the set with odd numbers are grouped together in fields.
Video compression typically reduces this redundancy using lossy compression.
en.wikipedia.org /wiki/Video_compression   (524 words)

  
 Video coding - Wikipedia, the free encyclopedia
Video coding is the field in computer science that deals with finding efficient coding formats for video that is digital (DV).
Modern video coding standards even include other multimedia data such as synthetic computer graphics, text and meta information for searching/browsing and digital rights management.
There are two special research areas that deal with multimedia compression: video compression and audio compression.
en.wikipedia.org /wiki/Video_coding   (254 words)

  
 Learn more about Video in the online encyclopedia.   (Site not responding. Last check: 2007-10-21)
Video is the technology of processing electronic signals representing moving pictures.
A major application of video technology is television, but it is also widely used in engineering, scientific, manufacturing, and security applications.
The term video is also used as abbreviation for videotape, as well as for video recorder and video player.
www.onlineencyclopedia.org /v/vi/video.html   (167 words)

  
 MPEG-2 video compression
One method of determining the motion that has occurred between the block being coded and the reference frame is a 'block-matching' search in which a large number of trial offsets are tested by the coder using the luminance component of the picture.
The coded luminance and chrominance prediction error is combined with 'side information' required by the decoder, such as motion vectors and synchronising information, and formed into a bitstream for transmission.
For example, the coding performance may vary depending on the quality of the motion-vector measurement, the techniques for controlling the bit rate, the methods used to choose between the different prediction modes, the degree of picture preprocessing and the way in which the quantiser is adapted according to the picture content.
www.bbc.co.uk /rd/pubs/papers/paper_14/paper_14.html   (4263 words)

  
 [No title]
For every video frame, the H.263 bitstream itself is carried in the RTP payload without alteration, including the picture start code, the entire picture header, in addition to any fixed length codes and variable length codes.
For H.263 video streams, the RTP timestamp is based on a 90 kHz clock, the same as the RTP timestamp for H.261 video streams [5].
The layout of an RTP H.263 video packet is shown as: 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
www.ietf.org /rfc/rfc2190.txt   (3660 words)

  
 Nokia - The next generation of video coding: MPEG-4 AVC
There is no single coding element in AVC coder responsible for the dramatic improvement in compression efficiency, compared to prior video coding standards.
Also, the number of bits required to code the prediction mode chosen for a given block was reduced, due to correlating between the prediction modes of adjacent blocks.
Context adaptive entropy coding: Another problem of the previous standards addressed during the AVC development, is the usage of a single set of VLC tables to code transform coefficients.
www.nokia.com /nokia/0,,57794,00.html   (1259 words)

  
 ADAPTIVE SOURCE-CHANNEL SUBBAND VIDEO CODING FOR WIRELESS CHANNELS
For each subband, the source coding rate as well as the level of protection (quantified by the channel coding rate) are jointly chosen to minimize the total mean-squared distortion suffered by the video coder.
The aim of a joint source-channel coding approach is to optimally allocate bits between the source and channel coders to minimize total distortion, while satisfying a constraint on the total rate.
These codes make it practical to achieve a wide range of channel coding rates using a single encoder and viterbi decoder by simply pucturing the coded bitstream according to the level of protection desired.
www.umiacs.umd.edu /users/murari/mmsp97/mmsp97.html   (1691 words)

  
 Optimal Bit Allocation for Coding of Video Signals over ATM Networks
In one, the video units are coded independently (e.g., motion JPEG), while in the other, the coding quality of a later picture may depend on that of an earlier picture (e.g., H.26x and MPEGx).
It is suboptimal in the case of VBR (variable bit-rate) transmission by the use of a suboptimal transmission rate control mechanism for simplicity.
For dependent coding, the Lagrange-multiplier approach becomes rather unwieldy, and a constrained tree search method is used.
www.comsoc.org /sac/private/1997/aug/1002_15sac06-chen.html   (559 words)

  
 H.263: Video CODEC for Medium Quality Videoconferencing
H.263 was developed to stream video at bandwidths as low as 20K to 24K bit/sec and was based on the H.261 codec.
The coding algorithm of H.263 is similar to that used by H.261, however with some improvements and changes to improve performance and error recovery.
Finally, a 12-byte H.263 payload header is defined in mode C to support fragmentation at MB boundaries for frames that are coded with the PB-frames option.
www.javvin.com /protocolH263.html   (988 words)

  
 4i2i: H.263 Video coding tutorial
Frames of video information are captured at the source and are encoded (compressed) by a video encoder.
A number of video coding standards exist, each of which is designed for a particular type of application: for example, JPEG for still images, MPEG2 for digital television and H.261 for ISDN video conferencing.
These codes are combined with synchronization and control information (such as the motion "vectors" required to reconstruct the motion-compensated reference frame) to form the encoded H.263 bitstream.
www.4i2i.com /h263_video_codec.htm   (1643 words)

  
 H.261: Video Coding and Decoding (CODEC) Overview
The coding algorithm is a hybrid of inter-picture prediction, transform coding, and motion compensation.
The data rate of the coding algorithm was designed to be able to be set to between 40 Kbits/s and 2 Mbits/s.
INTRA coding where blocks of 8x8 pixels each are encoded only with reference to themselves and are sent directly to the block transformation process.
www.javvin.com /protocolH261.html   (545 words)

  
 MPEG-4 description
The performance of error resilient video in the MPEG-4 Simple Profile was evaluated in subjective tests simulating MPEG-4 video carried in a realistic multiplex and over ditto radio channels, at bitrates between 32 kbit/s and 384 kbit/s.
The results show that the average video quality achieved on the mobile channel is high, that the impact of errors is effectively kept local by the tools in MPEG-4 video, and that the video quality recovers quickly at the end of periods of error.
The performance of error resilient video in MPEG-4 ARTS Profile was checked in subjective tests similar to those mentioned in the previous section, at bitrates between 32 kbit/s and 128 kbit/s.
www.chiariglione.org /mpeg/standards/mpeg-4/mpeg-4.htm   (8104 words)

  
 h264 video fastest mepg 4 encoder high-definition DVD
This profile is appropriate for efficient coding of interlaced television applications where bit or packet error is not excessive, and where low latency is not a requirement.
Any video application can benefit from a reduction in bandwidth requirements, but highest impact will involve applications where such reduction relieves a hard technical constraint, or which makes more cost-effective use of bandwidth as a limiting resource.
For video applications, retransmissions are impractical for dropped or delayed packets, so h.264 provides several means (e.g., FMO, data partitioning, etc.) to contain error impacts and facilitate error concealment.
www.pixeltools.com /h264_paper.html   (4350 words)

  
 Scalable Video Coding Using Foveation Model
The other is to design rate scalable video codecs, which allow the extraction of coded visual information at continuously varying bit rates from a single compressed bitstream.
In this paper, we follow these two trends and propose a foveation scalable video coding (FSVC) algorithm, which supplies good quality-compression performance as well as effective rate scalability to support simple and precise bit rate control.
The algorithm is amenable to the inclusion of various HVS models and adaptable to different video communication applications.
www.cns.nyu.edu /~zwang/files/papers/icassp01.html   (183 words)

  
 Image/Video Coding and Processing
Regunathan and K. Rose, "Efficient prediction in multiple description video coding," ICIP 2000, Vancouver, September 2000.
Regunathan and K. Rose, "Multimode Video coding for Noisy Channels," IEEE International Conference on Image Processing ICIP 97, October 1997.
Gersho and B. Ramamurthi, "Image Coding Using Vector Quantization," in Vector Quantization, H. Abut, editor, IEEE Press, New York, 1990 (reprint of 1982 paper), pp.
www.ece.ucsb.edu /scl/html/papers_A.htm   (2094 words)

  
 H.261 Video Coding
H.261 is video coding standard published by the ITU (International Telecom Union) in 1990.
The datarate of the coding algorithm was designed to be able to be set to between 40 Kbits/s and 2 Mbits/s.
Some example video sequences I have coded with the H.261 codec are shown below.
rice.ecs.soton.ac.uk /peter/h261/h261.html   (299 words)

  
 TECHNOLOGY CORNER
This naturally makes it attractive to video distributors, because it permits them to maximize the number of services that may be contained in a given amount of bandwidth.
The fundamental elements of the MPEG-4 coding process are the same as those of the earlier MPEG standards, which include prediction, transform, quantization and entropy coding.
H.264 permits the use of up to 32 previously coded pictures, and it supports more flexibility in the selection of motion compensation block sizes and shapes, down to the use of a luma compensation block as small as 4-by-4 pixels.
www.tvtechnology.com /features/Tech-Corner/F_Hoffner-03.09.05.shtml   (1137 words)

  
 CSE5302 - Digital Video Coding and Compression   (Site not responding. Last check: 2007-10-21)
be familiar with applications of digital video signal compression and their implementations.
Transform coding, including Karhunen Loeve transform, discrete Hadamard transform, discrete Walsh Hadamard transform, and discrete cosine transform, performance evaluation.
Hybrid coding algorithms and their applications to image and video encoding and compression.
www.csse.monash.edu.au /courseware/cse5302   (420 words)

  
 Object-Oriented H.263 Compatible Video Coding Platform for Conferencing Applications
This paper describes a prototype video coding platformThroughout this paper, the term "platform" is used to actually mean an encoding platform, which produces a compressed bit stream, and a decoding platform which produces decoded images from the bit stream.
A. Eleftheriadis and A. Jacquin, "Model-assisted coding of video teleconferencing sequences at low bit rates," in Proc.
D. Wang and J. Hartung, "Codebook adaptation algorithm for a scene adaptive video coder," in Proc.
www.comsoc.org /sac/private/1998/jan/42_16sac01-hartung.html   (488 words)

  
 DTV Guide Video Coding   (Site not responding. Last check: 2007-10-21)
TSI TR 101 154 V1.4.1, Digital Video Broadcasting (DVB): Implementation Guidelines for the use of MPEG-2 Systems, Video and Audio in Satellite, Cable and Terrestrial Broadcasting Applications, Annex B, July 2000.
Guidelines for use of the Digital Television Standard are outlined which ensure avoidance of conflict with DVB transport in the areas of packet identifier (PID) usage and assignment of user private values for descriptor tags and table identifiers.
This document describes the characteristics for the video subsystem of a digital television system operating at 25 Hz and 50 Hz frame rates.
www.atsc.org /document_map/video.htm   (955 words)

  
 MPEG . ORG - MPEG Video Resources and Software
Real-time MPEG Video Codec on a Single-chip Multiprocessor at Washington University
On the extraction of DC sequence from MPEG Compressed Video by Boon-Lock Yeo and Bede Liu
MPEG Video Compliance Bitstreams at HP Those are the Sarnoff Compliance Bitstreams, sold by HP.
www.mpeg.org /MPEG/video.html   (1521 words)

  
 Broadcom acquires Sand Video | The Register
Sand Video had a lead, albeit only a small one, in the silicon for the video encoding market, and Broadcom operates as market leader or close in every other broadband and communications chip market.
Faultline named Sand Video as one of its top 50 start-ups back in August last year after it launched the first silicon for the H.264 compression standard that is expected, with Windows Media 9, to drive next generation video compression.
Sand Video was funded by an $8m equity investment in November 2002, led by Baker Capital, which included Navigator Technology Ventures and a number of private investors from the CommonAngels of Boston.
www.theregister.co.uk /2004/04/13/broadcom_acquires_sand   (574 words)

  
 MainConcept- vendor of professional digital video solutions
We offer professional video editing and compositing programs, plus high-quality codecs that can be used in video production and in devices such as webcams and surveillance systems.
Apart from the Microsoft world, MainConcept is also one of the larges vendors of Linux video editing solutions that comply with the Video 4 Linux standard.
H.264 AVC (Advanced Video Coding) - also known as MPEG-4 Part 10 - is poised to be a major video standard because it can replace several popular formats while offering significant advantages over them.
www.mainconcept.com   (507 words)

  
 EETimes.com - Object-based video coding challenges MPEG
A Milpitas, Calif. startup will argue in the affirmative Monday (March 25) when it announces an object-based video coding algorithm that it calls a radical departure from the block-based coding used in all MPEG standards.
Like the Pulsent algorithm, many of the evolving coding technologies — including block-based H.26L, elements of which are being incorporated into a next-generation variant of MPEG-4 — target broadcast-quality video at 1.5 Mbits/second or slower.
"To do object-based video coding for a particular class of a picture is possible, but to do it for generic materials — sports, news, movies, science programs and the like — is very difficult." LeGall professed to have more "skepticism than faith" that such schemes will prove practical.
www.eetimes.com /story/OEG20020322S0105   (1685 words)

  
 MPEG . ORG - MPEG Starting Points and FAQs
Overviews specifically covering the MPEG Systems, Video or Audio standards have been moved to the systems, video and audio pages.
The Structure of the MPEG-4 Video Coding Algorithm at Heinrich-Hertz-Institut Berlin
The author, Mr Le Gall, was chairman of the Video Group of the MPEG committee.
www.mpeg.org /MPEG/starting-points.html   (2066 words)

  
 Wiley::H.264 and MPEG-4 Video Compression: Video Coding for Next-generation Multimedia
The new H.264 ‘Advanced Video Coding’ standard promises impressive compression performance and is gaining support from developers and manufacturers.  The first book to cover H.264 in technical detail, this unique resource takes an application-based approach to the two standards and the coding concepts that underpin them.
Introduces the basic concepts of digital video and covers essential background material required for an understanding of both standards.
Dr Iain Richardson leads the Image Communication Technology research group at the Robert Gordon University in Scotland and is the author of over 40 research papers and two previous books on video compression technology.
www.wiley.com /WileyCDA/WileyTitle/productCd-0470848375.html   (350 words)

  
 Strategies for Advanced Video Coding
H.264/AVC employs state-of-the-art video coding technologies and promises to have significant impact on future generations of video coding products, markets and services.
in coding efficiencies for the same quality when compared to existing standardized and proprietary technologies.
A brief overview of current hybrid video coding techniques and application parameters will be covered in the seminar.
www.knk-mpeg.com /strategies.htm   (538 words)

  
 H.263 Video Coding
I have coded some example video sequences with the H.263 codec they are shown below.
A comparison of H.263 with the H.261 video codec is also shown below.
The standard H.263 coding mode is used for the H.263 simulations at 10 and 30 frames/s.
rice.ecs.soton.ac.uk /peter/h263/h263.html   (673 words)

  
 Even Technologies Has Received a Purchase Order for the Production and Delivery of 1 Million CD's Deploying Its PSI CD ...   (Site not responding. Last check: 2007-10-21)
The Company's video disc solution enables content providers to distribute up to 2 hours of video on one single CD-ROM at visual DVD quality.
The PSI CD(TM) video disc solution has a rich list of features that allow content producers or replication companies to deliver up to 2 hours of premium video content at full D1 resolution.
Even Technologies Inc. (EVEN) is a Vancouver-based company specializing in the research of advanced digital image and video coding techniques, and in the development and integration of high-performance systems for media content production and dissemination over broadband networks.
www.forbes.com /businesswire/feeds/businesswire/2005/07/07/businesswire20050707005855r1.html   (850 words)

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