Standards
The organization now known as VCEG has standardized (and is responsible for the maintenance of) the following video compression formats and ancillary standards:
- H.120
- the first digital video coding standard. v1 (1984) featured conditional replenishment, differential PCM, scalar quantization, variable-length coding and a switch for quincunx sampling. v2 (1988) added motion compensation and background prediction. This standard was little-used and no codecs exist.
- H.261
- was the first practical digital video coding standard (late 1990). This design was a pioneering effort, and all subsequent international video coding standards have been based closely on its design. MPEG-1 Part 2 was heavily influenced by this.
- H.262
- it is identical in content to the video part of the ISO/IEC MPEG-2 Part 2 standard (ISO/IEC 13818-2). This standard was developed in a joint partnership between VCEG and MPEG, and thus it became published as a standard of both organizations. ITU-T Recommendation H.262 and ISO/IEC 13818-2 were developed and published as "common text" international standards. As a result, the two documents are completely identical in all aspects.
- H.263
- was developed as an evolutionary improvement based on experience from H.261, and the MPEG-1 and MPEG-2 standards. Its first version was completed in 1995 and provided a suitable replacement for H.261 at all bitrates. MPEG-4 Part 2 is substantially similar to this.
- H.263v2
- also known as H.263+ or as the 1998 version of H.263, is the informal name of the second edition of the H.263international video coding standard. It retains the entire technical content of the original version of the standard, but enhances H.263 capabilities by adding several annexes which substantially improve encoding efficiency and provide other capabilities (such as enhanced robustness against data loss in the transmission channel). The H.263+ project was completed in late 1997 or early 1998, and was then followed by an "H.263++" project that added a few more enhancements in late 2000.
- H.264
- Advanced Video Coding (AVC) is the newest entry in the series of international video coding standards. It is currently the most powerful and state-of-the-art standard, and was developed by a Joint Video Team (JVT) consisting of experts from ITU-T’s Video Coding Experts Group (VCEG) and ISO/IEC’s Moving Picture Experts Group (MPEG) created in 2001. The ITU-T H.264 standard and the ISO/IEC MPEG-4 Part 10 standard (formally, ISO/IEC 14496-10) are technically identical. The final drafting work on the first version of the standard was completed in May 2003. As has been the case with past standards, its design provides the most current balance between the coding efficiency, implementation complexity, and cost based on state of VLSI design technology (CPUs, DSPs, ASICs, FPGAs, etc.).
- H.264.1: Conformance testing for H.264
- H.264.2: Reference software for H.264
- H.265
- High Efficiency Video Coding, draft released Feb 2012, final standard expected in 2013.
- H.271
- Video back channel messages for conveyance of status information and requests from a video receiver to a video sender
For further information about the image coding work now in the domain of VCEG, see the Joint Photographic Experts Group article.
Read more about this topic: Video Coding Experts Group
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