Dav2d

(jbkempf.com)

113 points | by captain_bender 1 hour ago

7 comments

  • jordand 23 minutes ago
    'AV2 decoding is roughly five times more complex than AV1 decoding. In practice, that means software running on today’s hardware will struggle to decode AV2 in real time without careful, architecture-specific optimization'

    AV1 software decoding is already very intensive so AV2 decoding benchmarks are the next thing that would be really interesting (or mortifying) to see.

    • jbk 11 minutes ago
      > AV1 software decoding is already very intensive so AV2 decoding benchmarks are the next thing that would be really interesting (or mortifying) to see.

      Yes, this is going to be fun to watch.

  • aetherspawn 2 minutes ago
    Ok whose idea was ‘Wiener filtering’
  • husky8 4 minutes ago
    Is codex working on novel decoders 24/7? I hope
  • Slurpee99 24 minutes ago

      ... improvements around 25% compared to AV1
    
      AV2 decoding is roughly five times more complex than AV1 decoding
    
    I'm not sure what these two lines mean or if we can compare them, any help?
    • whynotmaybe 11 minutes ago
      I understood it as compression is 25% better : a quality of 10mbps in av1 can be achieved with 8mbps in Av2. But, it needs 5 times more compute power for this 25% gain.
    • jbk 13 minutes ago
      > I'm not sure what these two lines mean or if we can compare them, any help?

      AV2 saves 25% bandwidth at the cost of 5x more decoding complexity.

    • croes 18 minutes ago
      Smaller files but harder to decode
  • Eldodi 29 minutes ago
    How is AV2 expected to avoid the patent-pool issues AV1 ran into?

    AV1 was designed as royalty-free, but Sisvel’s pool and the recent Dolby/Snap proved the contrary.

    https://accessadvance.com/2026/03/24/access-advance-licensor...

    • UnlockedSecrets 25 minutes ago
      They filed a suit, henceforth making a claim of an issue...... They haven't "proved" anything other then they have lawyers on staff that can file some paperwork until the suit is settled in court...
    • AndrewDucker 21 minutes ago
      How does that prove anything?

      They're claiming that there are patents, but that doesn't mean there are.

      • Eldodi 17 minutes ago
        Dolby is only the most recent case, Sisvel consorsium actually bills licences per device:

        Consumer Display Device: EUR 0.32

        Consumer Non-Display Device: EUR 0.11

        (source here: https://www.sisvel.com/licensing-programmes/audio-and-video-...)

        • UnlockedSecrets 15 minutes ago
          How does how they bill for their product, matter in terms of if their lawsuit holds merit?
        • croes 16 minutes ago
          That doesn’t prove their claims are valid.

          I can claim the same and offer licenses per device.

    • croes 17 minutes ago
      No codec can ever avoid patent-pool claims.
    • Arodex 11 minutes ago
      Every single AV2 news here in the last week has seen exactly the same question.

      Either go back read the answers there first, or I will assume you are part of a FUD campaign (yes, I know HN guidelines, but again every single AV2 news in the last week has seen the same rhetorical "questions" as top "comments").

  • GaggiX 19 minutes ago
    I would love to see comparisons with AV1 on very low bitrates.
  • poly2it 20 minutes ago
    Sorry if this sounds naive, but does it make sense to write a codec library in C/ASM considering how well Rust is progressing, especially when, as the author puts it, AV2 decoding is roughly five times more complex than AV1 decoding?
    • Arodex 6 minutes ago
      The algorithms deployed in these kind of codecs take into account not only human vision and mathematical laws of information, but also nitty-gritty details of how computers work, which are optimally exploited by directly having humans write detailed assembly rather than a compiler make a best guess and effort.
    • jbk 12 minutes ago
      Because it's 5 times more complex, you need to get the maximum performance available. Therefore more ASM than ever.

      Rust does not bring more performance. Just more safety.

    • Telaneo 11 minutes ago
      Go ask FFmpeg what they're writing their encoders and decoders in.
    • MattRix 7 minutes ago
      Yes? There is 5x more code to optimize the ASM for.