Audio Video Standard

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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. [1]


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. [2] A patent pool charges a small royalty for terminal products (like TVs,) excluding content providers and operators. [3]

The AVS3 codec was added to DVB's media delivery toolbox. [4]



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. [5]

Patent pool

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. [6] 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. [7]


The AVS industry alliance is the abbreviation for Zhongguancun audio visual industry technology innovation alliance. In May 2005, twelve enterprises (units) of 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., Zhongguancun Hi-Tech Industry Association, established the AVS industry alliance in Beijing. The organization's English name is "AVS Industry Alliance" (AVSA), constituting "Three Carriages" with "AVS Workgroup" and "AVS Patent Pool Management Committee".

First generation

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, [8] 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. [9]

Second generation

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. [10]

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.


AVS2 adopts a hybrid-coding framework, and the whole coding process includes modules such as intra-frame prediction, inter-frame prediction, transformation, quantization, inverse quantization and inverse transformation, loop filter and entropy coding. It owns technical features as followings: [11]



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, [12] whilst uAVS3e can only be compiled for Windows and Linux. [13] uAVS3d and uAVS3e are released under the terms of the BSD 3-clause [12] and BSD 4-clause [13] licenses respectively.

FFmpeg v6 can make use of the uAVS3d library for AVS3-P2/IEEE1857.10 video decoding. [14]


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. [15] [16]


OpenAVS2 is a set of audio and video coding, transcoding and decoding software based on the AVS2 standard. [17]

xAVS2 & dAVS2

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 [18] [19] the xAVS2 library for AVS2-P2/IEEE1857.4 video encoding. [20] [21]

libdavs2 and libxavs2 are under the GNU Public License Version 2 or later.

See also

MPEG-5 Part1: EVC

MPEG-5 Part2: LC EVC

MPEGi Part 3: VVC = H.266 DVB approved / embraced / added

AV1 DVB approval in consideration / addition in progress

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  1. "Youwei Vision launches AVS3 8K video real-time decoder (in Chinese)". Tencent. May 29, 2019.
  2. "Introduction to AVSA". Official website of AVSA. Archived from the original on March 24, 2019. Retrieved September 29, 2017.
  3. "Who will lead the new video coding standard: a performance comparison report of HEVC、AVS2 and AV1". Archived from the original on July 28, 2018. Retrieved September 29, 2017.
  4. "AVS3 codec added to DVB's media delivery toolbox". July 7, 2022. Retrieved September 7, 2022.
  5. Elspeth Thomson, Jon Sigurdson, ed. (2008). China's Science and Technology Sector and the Forces of Globalisation. World Scientific Publishing. pp. 93–95. ISBN   978-981-277-101-8 . Retrieved June 15, 2022.
  6. 跳转提示.
  7. National Research Council (October 7, 2013). Patent Challenges for Standard-Setting in the Global Economy: Lessons from Information and Communications Technology. National Academies Press. ISBN   978-0-309-29315-0 . Retrieved June 15, 2022.
  8. Liu Baijia (March 6, 2006). "Standard Issue". China Business Weekly. Retrieved June 14, 2022.
  9. Xinhua (August 27, 2012). "China to promote its own audio-video coding standard". The Manilla Times. Retrieved June 15, 2022.
  10. IEEE Standard for Second-Generation IEEE 1857 Video Coding. IEEE STD 1857.4-2018. Institute of Electrical and Electronics Engineers. August 30, 2019. pp. 1–199. doi:10.1109/IEEESTD.2019.8821610. ISBN   978-1-5044-5461-2 . Retrieved June 13, 2022.
  11. "AVS2 special column".
  12. 1 2 uavs3d, UAVS, April 11, 2023, retrieved April 29, 2023
  13. 1 2 uavs3e, UAVS, April 4, 2023, retrieved April 29, 2023
  14. FFmpeg. "1.8 uavs3d" . Retrieved April 6, 2023.
  15. "High definition real-time encoder of AVS2 came out with better performance than x265 the encoder of HEVC/H.265".
  16. "AVS2 Real-time codec——uAVS2". Archived from the original on April 27, 2018. Retrieved September 29, 2017.
  17. "Official website of OpenAVS2". Archived from the original on December 31, 2019.
  18. FFmpeg. "1.7 dAVS2" . Retrieved April 6, 2023.
  19. dAVS2. "dAVS2". GitHub. Retrieved April 6, 2023.
  20. FFmpeg. "1.27 xAVS2" . Retrieved April 6, 2023.
  21. dAVS2. "dAVS2". GitHub. Retrieved April 6, 2023.