Китайский видеокодек AVS: Стандарты, развитие и применение.

Video codec

Audio Video Coding Standard (AVS) refers to the digital audio and digital video series compression standard formulated by the Audio and Video coding standard workgroup of China. Work began in 2002, and three generations of standards were published. The first generation AVS standard includes "Information Technology, Advanced Audio Video Coding, Part 2: Video" (AVS1) and "Information Technology, Advanced Audio Video Coding Part 16: Radio Television Video" (AVS+.) For the second generation, referred to as AVS2, the primary application target was ultra high definition television video, supporting the efficient compression of ultra high resolution (4K and above), high dynamic range videos, and was published as IEEE international standard IEEE 1857.4. An industry alliance was established to develop and promote AVS standards. A patent pool charges a small royalty for terminal products (like TVs,) excluding content providers and operators. The AVS3 codec was added to DVB's media delivery toolbox.

The AVS workgroup was founded in June 2002 to cooperate with Chinese enterprises and scientific research institutions, to formulate and revise common technical standards such as digital audio and digital video's compression, decompression, processing and representation, thus to provide efficient and economic coding/decoding technologies for digital audio and digital video devices and systems, serving the high resolution digital broadcasting, high density digital laser storage media, wireless broadband multimedia communication, Internet broadband streaming media, and other applications. The workgroup is headed by Gao Wen, the academician of Chinese Academy of Engineering, the professor and Ph. D. supervisor of Peking University, and the deputy director of the National Natural Science Fund Committee, consisting of a requirement group, system group, video group, audio group, test group, intellectual property group and other departments. The first setback was when China did not use AVS for its own digital television broadcast system in 2003.

A patent pool which manages and authorizes the patents was founded on September 20, 2004. The committee was the first patent pool management institution in China. An independent corporate association, the Beijing Haidian District Digital Audio and Video Standard Promotion Center, is registered in the Civil Affairs Bureau of Haidian District of Beijing City. for patent technologies included in the standard, as the expert committee and the main business decision making institution of the promotion center. The royalty for the first generation AVS standard was only one yuan per terminal. The plan was to charge a small amount of royalty only for the terminal, excluding the contents, as well as software services on the Internet.

The AVS Industry Alliance, short for Zhongguancun Audio Visual Industry Technology Innovation Alliance, was formed in May 2005 in Beijing by twelve entities, including TCL Group Co., Ltd., Skyworth Group Research Institute, Huawei Technology Co., Ltd., Hisense Group Co., Ltd., Haier Group Co., Ltd., Beijing Haier Guangke Co., Ltd., Inspur Group Co., Ltd., Joint Source Digital Audio Video Technology (Beijing) Co., Ltd., New Pudong District Mobile Communication Association, Sichuan Changhong Co., Ltd., Shanghai SVA (Group) Central Research Institute, Zte Communication Co., Ltd., and Zhongguancun Hi Tech Industry Association. The organization is also known as AVSA, and it collaborates with "AVS Workgroup" and "AVS Patent Pool Management Committee" as part of the "Three Carriages."

The first generation AVS standard included Chinese national standard "Information Technology, Advanced Audio Video Coding, Part 2: Video" (AVS1 for short, GB label：GB／T 20090.2 2006) and "Information Technology, Advanced Audio Video Coding Part 16: Radio Television Video" (AVS+ for short, GB label: GB/T 20090.16 2016). A test hosted by the Radio and Television Planning Institute of the State Administration of Radio, Film, and Television (SARFT, later part of the National Radio and Television Administration) shows: if the AVS1 bitrate is half of MPEG 2 standard, the coding quality will reach excellent for both standard definition or high definition; if the bitrate is less than 1/3, it also reaches good excellent levels. The AVS1 standard video part was promulgated as the Chinese national standard in February 2006. Around this time, AVS was considered for use in the enhanced versatile disc format, although products never reached the market. During the May 7–11, 2007 meeting of the ITU T (ITU Telecommunication Standardization Sector), AVS1 was one of the standards available for Internet Protocol television (IPTV) along with MPEG 2, H.264 and VC 1. On June 4, 2013, the AVS1 video part was issued by the Institute of Electrical and Electronics Engineers (IEEE) as standard IEEE1857 2013,
AVS+ is not only the radio, film and television industry standard GY/T 257.1 2012 "Advanced Audio Video Coding for Radio and Television, Part 1: Video" issued by the SARFT on July 10, 2012, but also the enhanced version of AVS1.

The second generation AVS standard included the series of Chinese national standard "Information Technology, Efficient Multi Media Coding" (AVS2). AVS2 mainly faces the transmission of extra HD TV programs,
The SARFT issued AVS2 video as the industry standard in May 2016, and as the Chinese national standard on December 30, 2016. AVS2 was published by the Institute of Electrical and Electronics Engineers (IEEE) as standard 1857.4 2018 in August, 2019. A test showed the coding efficiency of AVS2 more than doubled that of AVS+, and the compression rate surpassed the international standard HEVC (H.265). Compared with the first generation AVS standard, the second can save half transmission bandwidth.

uAVS3 is an open source and cross platform AVS3 encoder and decoder. The decoder (uAVS3d) and encoder (uAVS3e) support the AVS3 Phase2 baseline profile. uAVS3d can be compiled for Windows, Linux, macOS, iOS and Android, whilst uAVS3e can only be compiled for Windows and Linux. uAVS3d and uAVS3e are released under the terms of the BSD 3 clause

An encoder called uAVS2 was developed by the digital media research center of Peking University Shenzhen Graduate School. Subsequently, AVS2 Ultra HD real time video encoder and mobile HD encoder were announced.

OpenAVS2 is a set of audio and video coding, transcoding and decoding software based on the AVS2 standard.

xAVS2 and dAVS2 are open source encoder and decoder published by Peking University Video Coding Laboratory (PKU VCL) based on AVS2 P2/IEEE 1857.4 video coding standard, which is offered under either version 2 of the GNU General Public License (GPL) or a commercial license. FFmpeg Version 6 can make use of the dAVS2 library for AVS2 P2/IEEE1857.4 video decoding the xAVS2 library for AVS2 P2/IEEE1857.4 video encoding. libdavs2 and libxavs2 are under the GNU General Public License Version 2 or later.