Eagerly awaited across the tech industry, this week the Alliance for Open Media (AOMedia) has published the first complete version of the bitstream and decoding process specification for their royalty-free AV1 video codec. The release of the AV1 1.0 spec will enable backers of AOMedia to add support for the technology to their products or services, including taking the all-important step of finalizing the designs for the low-power hardware decoders critical for driving the codec's adoption. At least initially, AV1 will be used primarily for streaming video and user-generated content as an alternative to HEVC and its ongoing royalty disputes, but eventually adoption of AV1 may expand to other applications.

The AV1 open-source video codec was developed with 4K+ ultra-high-def resolutions, HDR, and wide color gamut in mind. Among the key features the new codec, AOMedia mentions a 30% more efficient compression algorithm compared to existing methods, predictable requirements for computational capabilities of hardware, and maximum flexibility and scalability. The backers of the AV1 want the codec to be ubiquitous across devices and platforms, therefore expect it to be supported not only by major chipmakers, software designers, and service providers, but also by leading makers of consumer electronics.

AOMedia does not disclose key technological peculiarities of the AV1 video codec in a short whitepaper form, meanwhile parsing through a 600-page bitstream and decoding spec for developers does not necessarily help to explain all the peculiarities of the tech in general. Therefore, I am going to limit technical details about the AV1 to a necessary minimum here.

On a high level, the AV1 is conceptually similar to existing codecs, such as H.264 or H.265. AV1 uses the same basic elements as various codecs have used for well over a decade: block-based coding, variable block sizes (up to 128x128 pixels), block motion compensation, intra-frame compression, forward-integer transform and so on. Meanwhile, since we are talking about compression algorithms more efficient than existing ones, it is natural that the AV1 has a number of advantages over contemporary codecs.

The AV1 performs internal processing in 8, 10 or 12 bits per sample precision, it also supports all three widespread types of chroma subsampling (4:2:0, 4:2:2, 4:4:4), and virtually all major color gamuts and formats (sRGB, BT.2020 (both 10-bit and 12-bit), BT.2100, etc.). The BT.2020 and the BT.2100 recommendations include support not only for 3840×2160, but also for 7680×4320 (8K) resolution, so the AV1 is technically ready for the next-gen monitors and TVs.

AV1 Profiles
seq_profile Bit Depth sRGB Gamut Support Chroma Subsampling
0 8 or 10 No YUV 4:2:0
1 8 or 10 Yes YUV 4:4:4
2 8 or 10 No YUV 4:2:2
2 12 Yes YUV 4:2:0
YUV 4:2:2
YUV 4:4:4

Speaking of displays, it is necessary to note that the AV1 was designed to be compatible with existing interconnections, such as DisplayPort, eDP, HDMI and so on. That said, the technology should also be compatible with contemporary content protection technologies.

The publication of the AV1 spec 1.0 is merely the first step towards adoption of the technology by the market. AOMedia expects content creation tools and desktop browsers to begin to roll out support for AV1 later this year. To ensure this, AOMedia released an unoptimized/experimental AV1 software decoder and encoder for use in software applications. Then, sometimes in 2019, the consortium anticipates select chips and programs to support the tech. More widespread support of the AV1 along with adoption by software is projected for 2020.

Speaking of adoption, the list of AOMedia members includes a variety of influential companies, including Apple, Amazon, AMD, Arm, Broadcom, Facebook, Google, Hulu, Intel, IBM, Microsoft, Netflix, NVIDIA, Realtek, Sigma and many others. These companies either control huge ecosystems themselves, or develop chips that are used by hundreds of millions of customers worldwide. Their support will ensure widespread adoption of the AV1 in the next decade. In the meantime, AOMedia has already started R&D for the AV2, which is to succeed the AV1 codec.

Related Reading:

Source: AOMedia



View All Comments

  • ViRGE - Sunday, April 1, 2018 - link

    I don't think the quality of Opus is in question, is it? (At least, not for sub-256kbps or so)

    Opus isn't used in mobile-class devices because AAC is "good enough" and there's hardware decode support. When someone adds Opus decoding to their SoC, then Google will presumably start feeding those devices Opus as wel.
  • ZolaIII - Sunday, April 1, 2018 - link

    Google is feeding them already as YouTube is Google app & decoder support is there already.
    As said before their is a FP implementation for Opus meaning it's suitable to bringing to DSP. So;
    This DSP isn't class leading, actually it's probably behind those used recently on Android mid tire phones and they implemented full range (both codec and hybrid) encoding and decoding. This is just for showing purposes. Libstagefright is old & not really good in fact whole audio api is deprecated & bad in many ways while hardware vendors never pulled tings together & offered a really good standardised solution on their own especially not unified one. Currently there are only two major players on this area the Tensilica and Qualcomm i don't know any solution from Tensilica but i know that Aqustic from QC is rather bad & supported by zero apps. OpenSL ES is supported as most spread alternative but pore implemented with basics only. So in the end chances are that you will end up using the costume solution that is integer only on both sides (or FP on codec side in the best case) codec & output anyway as Foobar2000, Neutron, Viper... So in other words lo power hardware audio is dead on Android for a long time. We will see what will open alliance choose as their favourite and how it will be implemented all do Opus looks like a logical choice unfortunately it's not a complete one as it's up to stereo only with up to 256 channels (for mixing - mastering). For now Opus is fairly good adopted regardless of platform and architecture and that support is only growing.
    Best regards.
  • tuxRoller - Saturday, March 31, 2018 - link

    E tu, opus?
    What have you against the best available tech?
  • BurntMyBacon - Friday, March 30, 2018 - link

    @npz: "I bet you if Google made stats available of when h.264 is used vs VP9 you'll see it overwhelmingly in favor of h.264."

    In other words, you don't really know. You simply suspect. All that talk about how it is not successful and only gets used in specific circumstances is supposition. I'm not going to say you are wrong as I also don't know, but you made some pretty strong statements for not knowing.

    @npz: "AV1 is supposed to compete with h.265 .."

    Actually they are positioning it as a successor to h.265 and they have comparisons showing the supposed superiority of AV1.

    @npz: "If AV1 started at the same time as h.265 several years ago I could see AV1 taking off, but since h.265 has already been established it has the economic network effect in its favor."

    When h.265 was released, it had to compete with h.264 with its establishment and economic network in effect. It wins based on industry support and technical superiority. There will always be a pre-existing standard that is already well established and supported. If AV1 really does have significant technical superiority and can gather enough support in the industry, hardware acceleration and economic buy in will follow.
  • npz - Friday, March 30, 2018 - link

    The burden of proof is on YOUR end given that Ive shown you how the youtube algorithms work for stream cofec preferences and have at least anecdotal evidence to back it up that anyone can duplicate by lookung at the stream stats (enable stats for nerds settings on moblie) on their device. You had claimed VP9 was widely successful so show me proof of it displacing h264 in the market.
    And that is merely for the consumer side.

    Where is the proof VP9 is used over
  • npz - Friday, March 30, 2018 - link

    Over h264 on the professional side? Where are the cametas and broadcast equipment support? Reply
  • npz - Friday, March 30, 2018 - link

    AV1 needs more than just net and gpu companies. They need the entire ecosystem to actually implement it in software and hardware both on the consumption and production side.

    I will believe technical superiority when I actually see it. That claim was made about VP8 wrt h.264 and it absolutely wasn't true nor was it true for VP9 either. The psycho optimizations x264 makes kicks Google's reference VP9 encoder as well as other h
  • npz - Friday, March 30, 2018 - link

    other h264 encoders arse back and forth. Reply
  • ZeDestructor - Monday, April 2, 2018 - link

    >Where is the proof VP9 is used over h264 on the professional side? Where are the cametas and

    Neither is used on the pro side. They use some form of raw/lossless codec. Typically ProRes or REDcode to on-board media, or raw SDI/HDMI to external capture.

    >broadcast equipment support?

    Unlike on computers and computer-like devices, broadcast equipment is much less easily upgraded, particularly the STBs. So when your 1st gen STBs show up only supporting H.264 and/or H.265, that's what you're stuck with until the next generation of equipment. Unless you want to pay even more to be able to waste valuable bandwidth transmitting stuff in duplicate.

    With how early AV1 has showed up though, there is a decent chance that it will make it into the next generation of broadcast standards. Especially given that the BBC and CableLabs are involved.

    >AV1 needs more than just net and gpu companies. They need the entire ecosystem to actually implement it in software and hardware both on the consumption and production side.

    If you ram it down hard enough, the rest of the ecosystem follows. As of right now, the entirety of the desktop market (all Intel, nVidia, Intel), and a huge segment of the mobile ecosystem (ARM, Apple) are all backing AV1. The only ones left are the Android SoC vendors like Qualcomm. I touched on that in my comment on this story (the very first one in fact). Yes, I am slightly worried, but given how everyone not Google folded and integrated hardware VP8/VP9 support, things are looking rather positive

    >I will believe technical superiority when I actually see it. That claim was made about VP8 wrt h.264 and it absolutely wasn't true nor was it true for VP9 either. The psycho optimizations x264 makes kicks Google's reference VP9 encoder as well as other h264 encoders arse back and forth

    The math behind pSNR puts VP8 and VP9 as about equal to to H.264 and H.265. Sure, psychovisual optimizations are a thing, but there's nothing stopping it being added to any newer encoder. Alternatively, you can just crank up the bitrate a bit and get better quality both perceptually and mathematically
  • ZolaIII - Tuesday, April 3, 2018 - link

    Yes OpenH264 & XH264 implementations are much better then reference ones & beat even the Vp9 and H265 reference one's but forget about their hardware implementation (at least I don't know any up to date, its not that it can't be brought to existing DSP's but just highly unlikely we will see it). In short that's the poppy power of Open Source (in it's best). Now sometimes that is from a stretch & by all means designed as a Open source will have much better adoption in the same community meaning it will be improved even more & much faster. This is why & how AV1 will shine. Reply

Log in

Don't have an account? Sign up now