Advanced Video Coding: Difference between revisions

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'''Advanced Video Coding''' ('''AVC'''), also referred to as '''H.264''' or '''MPEG-4 Part 10''', is a [[video compression standard]] based on block-oriented, [[motion compensation|motion-compensated]] coding.<ref>{{Cite web|url=https://www.itu.int/rec/T-REC-H.264|title=H.264 : Advanced video coding for generic audiovisual services|website=www.itu.int|url-status=live|archive-url=https://web.archive.org/web/20191031100750/https://www.itu.int/rec/T-REC-H.264|archive-date=2019-10-31|access-date=2019-11-22}}</ref> It is by far the most commonly used format for the recording, compression, and distribution of video content, used by 91% of video industry developers {{as of|September 2019|lc=on}}.<ref>{{cite web|url=https://go.bitmovin.com/hubfs/Bitmovin-Video-Developer-Report-2018.pdf|title=Video Developer Report 2018 |website=[[Bitmovin]] |date=September 2019}}</ref><ref>{{cite web |url=https://go.bitmovin.com/video-developer-report-2019 |title=Video Developer Report 2019 |website=[[Bitmovin]] |date=September 2019}}</ref> It supports a maximum resolution of [[8K resolution|8K UHD]].<ref>{{Cite news|url=http://www.mysterybox.us/blog/2017/2/21/delivering-8k-using-avch264|archive-url=https://web.archive.org/web/20210325084239/https://www.mysterybox.us/blog/2017/2/21/delivering-8k-using-avch264 | archive-date=March 25, 2021|title=Delivering 8K using AVC/H.264|work=Mystery Box|access-date=2017-08-23|language=en-US}}</ref><ref name="Wang" />

The intent of the H.264/AVC project was to create a standard capable of providing good video quality at substantially lower [[bit rate]]s than previous standards (i.e., half or less the bit rate of [[H.262/MPEG-2 Part 2|MPEG-2]], [[H.263]], or [[MPEG-4 Part 2]]), without increasing the complexity of design so much that it would be impractical or excessively expensive to implement. This was achieved with features such as a reduced-complexity integer [[discrete cosine transform]] (integer DCT),<ref name="apple"/> variable block-size segmentation, and multi-picture [[inter frame|inter-picture prediction]]. An additional goal was to provide enough flexibility to allow the standard to be applied to a wide variety of applications on a wide variety of networks and systems, including low and high bit rates, low and high resolution video, [[Broadcasting|broadcast]], [[DVD]] storage, [[Real-time Transport Protocol|RTP]]/[[Internet Protocol|IP]] packet networks, and [[ITU-T]] multimedia [[telephony]] systems. ItsThe skillH.264 instandard balancingcan filebe sizeviewed andas videoa quality"family hasof madestandards" itcomposed the de facto standard forof a number of uses, including Blu-ray disc manufacture and streaming services.<ref>{{Cite web |last=Tina |first=Celluadifferent |date=Novprofiles, 21.although 2023its |title=HEVC"High vs.profile" AVC,is Whichby Onefar isthe Bettermost forcommonly Liveused Streaming? |url=https://wwwformat.ddmalltech.com/blogs/articles/hevc-vs-avc-for-live-streaming |url-status=live}}</ref> A specific decoder decodes at least one, but not necessarily all profiles. The standard describes the format of the encoded data and how the data is decoded, but it does not specify algorithms for encoding video{{snd}} that is left open as a matter for encoder designers to select for themselves, and a wide variety of encoding schemes have been developed. H.264 is typically used for [[lossy compression]], although it is also possible to create truly [[lossless compression|lossless-coded]] regions within lossy-coded pictures or to support rare use cases for which the entire encoding is lossless.

H.264 was standardized by the [[ITU-T]] [[Video Coding Experts Group]] (VCEG) of [[ITU-T Study Group 16|Study Group 16]] together with the [[ISO/IEC JTC 1]] [[Moving Picture Experts Group]] (MPEG). The project partnership effort is known as the Joint Video Team (JVT). The ITU-T H.264 standard and the ISO/IEC [[MPEG-4]]&nbsp;AVC standard (formally, ISO/IEC&nbsp;14496-10&nbsp;– MPEG-4 Part 10, Advanced Video Coding) are jointly maintained so that they have identical technical content. The final drafting work on the first version of the standard was completed in May 2003, and various extensions of its capabilities have been added in subsequent editions. [[High Efficiency Video Coding]] (HEVC), a.k.a. H.265 and MPEG-H Part 2 is a successor to H.264/MPEG-4&nbsp;AVC developed by the same organizations, while earlier standards are still in common use.