2.5 Video Codec Standards
2.5.1 Standardization Bodies
Standardization of video codecs is critical in ensuring their widespread adoption. Currently, video codec standards are published by two separate bodies:
- International Telecommunications Union (ITU): as its name suggests, the ITU produces standards relevant for use in communications. It has been responsible for publishing the H.26x series of video coding standards. Note that audio, speech, and multiplexing standards are published separately by the ITU.
- International Organization for Standardization (ISO): the ISO publishes the MPEG (Motion Picture Experts Group) series of standards. These standards generally contain a video coding part, an audio coding part, and a systems part. The systems part provides a specification of how to multiplex audio-visual streams.
Experts from the two standardization bodies have cooperated under the umbrella of the Joint Video Team (JVT). This cooperation has led to joint standardization of video codecs, where the same standardized codecs are published by both the ISO and the ITU, but under different names (e.g. MPEG-4 AVC is the same as H.264).
2.5.2 ITU Standards
The ITU standardized the first digital video codec in 1984, which was called H.120 . The first version of the codec featured some very basic compression techniques, such as conditional replenishment, differential pulse code modulation (DPCM), scalar quantization, and variable length coding. An updated version was produced in 1988, ...