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Audio Video Coding Standard (AVS) refers to the digital audio and digital video series compression standard formulated by Audio and Video coding standard workgroup of China according to the open international rules. At present, the formulation of two-generation AVS standards has been completed.
The first generation AVS standard includes “Information Technology, Advanced Audio Video Coding, Part 2: Video” (AVS1 for short) and “Information Technology, Advanced Audio Video Coding Part 16: Radio Television Video” (AVS+ for short).
For the second generation AVS standard, referred to as AVS2, the primary application target is Ultra HD (High Definition) video, supporting the efficient compression of ultra high-resolution (4K above), HDR (High Dynamic Range) videos, and it has been submitted to the IEEE international standard (Standard No.: IEEE1857.4) for application.
The “AVS Patent Pool” provides one-stop authorization for AVS standard, which charges only a small amount of royalties for terminal products, excluding content providers and operators. The royalty for the first generation AVS standard is one yuan per terminal.
In order to propel the development and promotion of the AVS standard, Huawei, TCL, Skyworth and other companies established Zhongguancun audiovisual industry technology innovation alliance (abbreviation: AVS industry alliance), which is devoted to the development and promotion of the AVS standard.
The AVS workgroup is the abbreviation for the digital audio and video coding standard workgroup, founded in June 2002. Its mission is to cooperate with domestic enterprises and scientific research institutions, facing the requirements of the information industry, to formulate (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 major information industry applications. Currently the AVS workgroup is composed of 81 member units from universities, enterprises and scientific research institutions, which are 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 requirement group, system group, video group, audio group, test group, intellectual property group and other departments. Since its establishment, the AVS working group has been persisting in formulating AVS series standards in accordance with open international rules. And two-generation AVS standards have been formulated so far.
In the aspect of intellectual property management, AVS established a "Patent Pool" management mechanism, with the management and authorization of the patent pool in charge of “AVS Patent Pool Management Committee”, an independent corporate association founded in September 20, 2004. The committee is also the first "Patent Pool" management institution in China. Relying on the independent corporate association “Beijing Haidian District Digital Audio and Video Standard Promotion Center” registered in the Civil Affairs Bureau of Haidian District of Beijing City, it set up one-stop, low-cost patent authorization principles and management rulesfor 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 is only charged one-yuan per terminal, and the same mode will be adopted for the second generation, to charge a small amount of royalty only for the terminal, excluding the contents, as well as software services on the Internet.
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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, volunteered to jointly launch and establish the AVS industry alliance in Beijing, in order to propel the industrialization progress of AVS as soon as possible, and form a complete industrial chain and multi-manufacturer supply environment soon, further to inject a strong power into the development of Chinese audio and video industry. The organization's English name is "AVS Industry Alliance", referred to as "AVSA", constituting mutually independent and supportive "Three Carriages" with "AVS Workgroup" and "AVS Patent Pool Management Committee". The AVSA is committed to constructing a complete digital audio and video “technology→patent→standard→chip and software→whole machine and system manufacturing→digital media operation and culture industry” industry chain, creating a comprehensive breakthrough of the standard formulation, rapid technological progress and industrial leapfrogging development, achieving the overall rising of the digital AV industry, and forming a digital AV enterprise group with significant impact on the world. At present, the total number of alliance members is 117, including 81 standard members, and 36 industrial promotion members.
The first generation AVS standard includes 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). The AVS video standard test hosted by the Radio and Television Planning Institute of SARFT (State Administration of Radio, Film, and Television) 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.
During May 7–11, 2007, the fourth meeting of the ITU-T (The ITU Telecommunication Standardization Sector) IPTV FG made it clear that the AVS1 became one of the standards available for IPTV selection ranked with MPEG-2, H.264 and VC-1. On June 4, 2013, the AVS1 video part was issued by the most influential academic organization IEEE (Institute of Electrical and Electronics Engineers) in the field of international electronic information, with Standard Number IEEE1857-2013, marking that the AVS series of standards made an important step on the internationalization road.
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. Until now, Chinese AVS standard has landed in Sri Lanka, Laos, Thailand, Kyrgyzstan, and other countries, so that thousands of sets of HD contents applying AVS+ coding have been broadcast through satellite channels worldwide.
The second-generation AVS standard includes the series of Chinese national standard “Information Technology, Efficient Multi Media Coding” (AVS2 for short). The AVS2 mainly faces the transmission of extra HD TV programs, aiming at leading the development of the digital media industry in the next five to ten years, and striving to play a key role in the formulation of relevant international standards. At the same time of the promotion and application of the first generation AVS standard, the continued evolution work of AVS technology is being actively advanced, and the development of the second generation standard AVS2 technology has been completed. The SARFT issued AVS2 video as the industry standard in May 2016, and as the Chinese national standard on December 30, 2016. Currently, it has been submitted to the IEEE international standard (Standard Number: IEEE1857.4) for application.
The test of authoritative institutions shows, the coding efficiency of AVS2 is improved higher than doubled that of AVS+, and the compression rate surpasses the latest international standard HEVC (H.265). Compared with the first generation AVS standard, the second can save half transmission bandwidth, and will support the promotion and application of extra HD TV in the next few years.
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:
uAVS2 is the world's first HD real-time encoder based on the AVS2 standard, successfully developed by the digital media research center of Shenzhen Graduate School of Peking University, with performance dramatically beyond the x265 HEVC/H.265 encoder, which has eliminated technical obstacles to enable the AVS2 standard into industrial application. Subsequently, AVS2 Ultra HD real-time video encoder and mobile HD encoder have also been launched in succession.
OpenAVS2 is a set of mature industrial audio and video coding, transcoding and decoding kit based on the AVS2 standard, covering the mobile Internet, the Internet core applications and vertical industries, working out mature one-stop AVS2 audiovisual industry solutions.
xAVS2 and dAVS2 are open-sourced 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.
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JPEG is a commonly used method of lossy compression for digital images, particularly for those images produced by digital photography. The degree of compression can be adjusted, allowing a selectable tradeoff between storage size and image quality. JPEG typically achieves 10:1 compression with little perceptible loss in image quality.
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H.261 is an ITU-T video compression standard, first ratified in November 1988. It is the first member of the H.26x family of video coding standards in the domain of the ITU-T Video Coding Experts Group (VCEG), and was the first video coding standard that was useful in practical terms.
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VP8 is an open and royalty free video compression format owned by Google and created by On2 Technologies as a successor to VP7.
High Efficiency Video Coding (HEVC), also known as H.265 and MPEG-H Part 2, is a video compression standard, designed as a successor to the widely used AVC. In comparison to AVC, HEVC offers from 25% to 50% better data compression at the same level of video quality, or substantially improved video quality at the same bit rate. It supports resolutions up to 8192×4320, including 8K UHD, and unlike the primarily 8-bit AVC, HEVC's higher fidelity Main10 profile has been incorporated into nearly all supporting hardware. HEVC is competing with the AV1 coding format for standardization by the video standard working group NetVC of the Internet Engineering Task Force (IETF).
AOMedia Video 1 (AV1) is an open, royalty-free video coding format designed for video transmissions over the Internet. It was developed by the Alliance for Open Media (AOMedia), a consortium of firms from the semiconductor industry, video on demand providers, video content producers, software development companies and web browser vendors, founded in 2015. The AV1 bitstream specification includes a reference video codec. It succeeds VP9. It can have 20% higher data compression than VP9 or HEVC/H.265 from the Moving Picture Experts Group and about 50% higher than the widely used AVC.