A video coding format (or sometimes video compression format) is an encoded format of digital video content, such as in a data file or bitstream. It typically uses a standardized video compression algorithm, most commonly based on discrete cosine transform (DCT) coding and motion compensation. A computer software or hardware component that compresses or decompresses a specific video coding format is a video codec.
Some video coding formats are documented by a detailed technical specification document known as a video coding specification. Some such specifications are written and approved by standardization organizations as technical standards, and are thus known as a video coding standard. There are de facto standards and formal standards.
Video content encoded using a particular video coding format is normally bundled with an audio stream (encoded using an audio coding format) inside a multimedia container format such as AVI, MP4, FLV, RealMedia, or Matroska. As such, the user normally does not have a H.264 file, but instead has a video file, which is an MP4 container of H.264-encoded video, normally alongside AAC-encoded audio. Multimedia container formats can contain one of several different video coding formats; for example, the MP4 container format can contain video coding formats such as MPEG-2 Part 2 or H.264. Another example is the initial specification for the file type WebM, which specifies the container format (Matroska), but also exactly which video (VP8) and audio (Vorbis) compression format is inside the Matroska container, even though Matroska is capable of containing VP9 video, and Opus audio support was later added to the WebM specification.
kbit/s) available until the 1990s. Similarly, uncompressed
high-definition (HD)
1080p video requires bitrates exceeding 1
As of 2019, AVC is by far the most commonly used format for the recording, compression, and distribution of video content, used by 91% of video developers, followed by HEVC, which is used by 43% of developers.
List of video coding standards
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Timeline of international video compression standards
| Basic algorithm |
Video coding standard |
Year |
Publishers |
Committees |
Licensors |
Market presence ——N/a
| QuickTime |
| MPEG-1 Part 2 |
1993 | ISO, IEC |
MPEG |
Fujitsu, IBM, Matsushita, etc. |
Unknown |
Camcorders, digital cassettes |
| H.263 |
1996 | ITU-T |
VCEG |
Mitsubishi, Hitachi, Panasonic, etc. |
——Unknown |
Blu-ray, Internet video |
| Apple ProRes |
2007 |
Apple |
Apple |
Apple |
| N/a
7% |
HTML video |
| Versatile Video Coding (VVC / H.266) |
2020 |
JVET |
JVET |
| N/a
|
Interframe compression complicates editing of an encoded video sequence.
One subclass of relatively simple video coding formats are the intra-frame video formats, such as DV, in which each frame of the video stream is compressed independently without referring to other frames in the stream, and no attempt is made to take advantage of correlations between successive pictures over time for better compression. One example is Motion JPEG, which is simply a sequence of individually JPEG-compressed images. This approach is quick and simple, at the expense of the encoded video being much larger than a video coding format supporting Inter frame coding.
Because interframe compression copies data from one frame to another, if the original frame is simply cut out (or lost in transmission), the following frames cannot be reconstructed properly. Making cuts in intraframe-compressed video while video editing is almost as easy as editing uncompressed video: one finds the beginning and ending of each frame, and simply copies bit-for-bit each frame that one wants to keep, and discards the frames one does not want. Another difference between intraframe and interframe compression is that, with intraframe systems, each frame uses a similar amount of data. In most interframe systems, certain frames (such as I-frames in MPEG-2) are not allowed to copy data from other frames, so they require much more data than other frames nearby.
It is possible to build a computer-based video editor that spots problems caused when I frames are edited out while other frames need them. This has allowed newer formats like HDV to be used for editing. However, this process demands a lot more computing power than editing intraframe compressed video with the same picture quality. But, this compression is not very effective to use for any audio format.
A video coding format can define optional restrictions to encoded video, called profiles and levels. It is possible to have a decoder that only supports decoding a subset of profiles and levels of a given video format, for example, to make the decoder program/hardware smaller, simpler, or faster."SERIES H: AUDIOVISUAL AND MULTIMEDIA SYSTEMS : Infrastructure of audiovisual services – Coding of moving video : Advanced video coding for generic audiovisual services". Itu.int. Retrieved January 6, 2015.
↑ "Audio/Video". The Chromium Projects. Retrieved May 23, 2016.
↑ "Chapter 3 : Modified A* Prune Algorithm for finding K-MCSP in video compression" (PDF). Shodhganga.inflibnet.ac.in. Retrieved January 6, 2015.
1 2 3 4 5 6 7 8 9 10 Ghanbari, Mohammed (2003). Standard Codecs: Image Compression to Advanced Video Coding. Institution of Engineering and Technology. pp. 1–2. ISBN 9780852967102.
1 2 3 4 5 6 Ahmed, Nasir (January 1991). "How I Came Up With the Discrete Cosine Transform". Digital Signal Processing. 1 (1): 4–5. Bibcode:1991DSP.....1....4A. doi:10.1016/1051-2004(91)90086-Z.
↑ Habibi, Ali (1974). "Hybrid Coding of Pictorial Data". IEEE Transactions on Communications. 22 (5): 614–624. Bibcode:1974ITCom..22..614H. doi:10.1109/TCOM.1974.1092258.
↑ Ohm, Jens-Rainer (2015). Multimedia Signal Coding and Transmission. Springer. p. 364. ISBN 9783662466919.
1 2 Stanković, Radomir S.; Astola, Jaakko T. (2012). "Reminiscences of the Early Work in DCT: Interview with K.R. Rao" (PDF). Reprints from the Early Days of Information Sciences. 60. Retrieved October 13, 2019.
↑ Cianci, Philip J. (2014). High Definition Television: The Creation, Development and Implementation of HDTV Technology. McFarland. p. 63. ISBN 9780786487974.
1 2 3 "ITU-T Recommendation declared patent(s)". ITU. Retrieved July 12, 2019.
1 2 "MPEG-4 Visual - Patent List" (PDF). MPEG LA. Archived from the original (PDF) on July 6, 2019. Retrieved July 6, 2019.
1 2 3 Wang, Hanli; Kwong, S.; Kok, C. (2006). "Efficient prediction algorithm of integer DCT coefficients for H.264/AVC optimization". IEEE Transactions on Circuits and Systems for Video Technology. 16 (4): 547–552. Bibcode:2006ITCSV..16..547W. doi:10.1109/TCSVT.2006.871390.
↑ Thomson, Gavin; Shah, Athar (2017). "Introducing HEIF and HEVC" (PDF). Apple Inc. Retrieved August 5, 2019.
1 2 "ISO Standards and Patents". ISO. Retrieved July 10, 2019.
↑ "Motion JPEG 2000 Part 3". Joint Photographic Experts Group, JPEG, and Joint Bi-level Image experts Group, JBIG. Archived from the original on October 5, 2012. Retrieved June 21, 2014.
↑ "VC-1 Patent List" (PDF). MPEG LA. Archived from the original (PDF) on July 6, 2019. Retrieved July 11, 2019.
↑ Bhojani, D.R. "4.1 Video Compression" (PDF). Hypothesis. Archived from the original (PDF) on May 10, 2013. Retrieved March 6, 2013.
↑ Jan Ozer. "Encoding options for H.264 video". Adobe.com. Retrieved January 6, 2015.
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