IDT Partners

  • history YouTube
  • YouTube Premium
  • Social impact YouTube
  • about 
  • solutions 
  • careers 
  • AV1

    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.

    The roots of the project precede the Alliance, however. Individual contributors started experimental technology platforms years before: Xiph's/Mozilla's Daala already published code in 2010, Google's experimental VP9 evolution project VP10 was announced on 12 September 2014, and Cisco's Thor was published on 11 August 2015. Building on the codebase of VP9, AV1 incorporates additional techniques, several of which were developed in these experimental formats. The first version 0.1.0 of the AV1 reference codec was published on 7 April 2016.

    To fulfill the goal of being royalty free, the development process is such that no feature is adopted before it has been independently double checked to not infringe on patents of competing companies. In cases where working around a patent-protected technique hasn't been possible, owners of relevant patents have been invited to join the Alliance, even if they were already members of another patent pool. For example, Alliance members Apple, Cisco, Google, and Microsoft are also licensors in MPEG-LA's patent pool for H.264. In addition, the Alliance has a legal defense fund to aid smaller Alliance members or AV1 licensees in case they're sued.

    The pursuit of royalty-free web standards has historical precedence and can have many reasons. In 2007, the proposal for HTML5 video specified Theora as mandatory to implement. The reason given was that public content should be encoded in freely implementable formats, if only as a Şbaseline formatÉ, and that changing such a baseline format later would be hard because of network effects. The Alliance for Open Media is a continuation of Google's efforts with the WebM project, which renewed the royalty-free competition after Theora had been surpassed by AVC. AVC is hard for (among others) Mozilla to support, the problem being that a per-copy royalty easily is unsustainable for software that is distributed free of charge (see FRAND Ë Excluding costless distribution). HEVC is likewise ÷ an exception for freely distributed software has not been made by all licensors (see HEVC Ë Provision for costless software).

    Frame content is separated into adjacent same-sized blocks referred to as superblocks. Similar to the concept of a macroblock, superblocks are square-shaped and can either be of size 128§128 or 64§64 pixels. Superblocks can be divided in smaller blocks according to different partitioning patterns. The four-way split pattern is the only pattern whose partitions can be recursively subdivided. This allows superblocks to be divided into partitions as small as 4§4 pixels.

    Ozer noted that his and Bitmovin's results contradicted a comparison by Fraunhofer Institute for Telecommunications from late 2016 that had found AV1 38.4% less efficient than HEVC, underperforming even H.264/AVC, and justified this discrepancy by having used encoding parameters endorsed by each encoder vendor, as well as having more features in the newer AV1 encoder.

    According to Mukund Srinivasan, chief business officer of AOM member Ittiam, early hardware support will be dominated by software running on non-CPU hardware (such as GPGPU, DSP or shader programs, as is the case with some VP9 hardware implementations), as fixed-function hardware will take 12ľ18 months after bitstream freeze until chips are available, plus 6 months for products based on those chips to hit the market. The bitstream was finally frozen on 28 March 2018, meaning chips could be available sometime between March and August 2019. According to the above forecast, products based on chips could then be on the market at the end of 2019 or the beginning of 2020.

    The AV1 Image File Format (AVIF) is a specification for storing images or image sequences compressed with AV1 in the HEIF file format. AVIF files conform to the HEIC specification and support features like High Dynamic Range (HDR) and wide color gamut (WCG).