Dav2d

(code.videolan.org)

238 points | by dabinat 4 hours ago

11 comments

  • jzebedee 3 hours ago
    Project description:

      dav2d is the fastest AV2 decoder on all platforms :)
      Targeted to be small, portable and very fast.
    
    If you're out of the loop like me:

      AV2 is the next-generation video coding specification from the Alliance for Open Media (AOMedia). Building on the foundation of AV1, AV2 is engineered to provide superior compression efficiency, enabling high-quality video delivery at significantly lower bitrates. It is optimized for the evolving demands of streaming, broadcasting, and real-time video conferencing. 
    
    - from https://av2.aomedia.org/
    • delfinom 2 hours ago
      • Telaneo 2 hours ago
        They've done the same thing with AV1, and I can't see that having prevented adoption, nor can I imagine Sisvel wanting to poke the bear that is AOMedia unless they're certain their case is absolutely watertight.
        • walrus01 2 hours ago
          I see zero public evidence that they've filed any lawsuits against the members of AOM in any jurisdiction. I'm sure there's been a lot of threatening letters sent...
          • jorvi 1 hour ago
            Yup. The Dolby/Disney vs Snapchat lawsuit is going to be the first one. So far it's only been filed.

            The big question is if AOMedia is going to make good on their Mutually Assured Destruction promise of using their patent and financial war chest to to countersue into oblivion anyone trying to go after AV1 adaptors.

            • dmitrygr 15 minutes ago
              I would love to live in a world where this happens. I will place big bets that it will, regrettably not happen.
          • Telaneo 2 hours ago
            Same, which is what makes it seem to me that that case is absolutely not watertight. Those patents are probably all about esoteric minutiae (to be fair, that's because that's what it takes to make a better video codec these days) and everything and anything that can seemingly be connected to AV2 (or AV1 for that matter), many of which have only gotten a patent because the person approving it only barely understands what it's saying.
      • ronsor 1 hour ago
        This is a thinly veiled extortion racket and any competent system would fine them into bankruptcy.
        • mort96 40 minutes ago
          We need a more efficient way to eliminate bullshit patents or bullshit patent infringement claims than "violate them then spend millions on lawyers to fight them in court".
          • brookst 38 minutes ago
            Sure, and at the same time we need a more efficient way to ensure big companies can’t just take what they want and bury anyone who complains.

            It’s not an easy problem.

      • walrus01 2 hours ago
        Sisvel is a patent troll. Take a look at the combined list of all companies that are the AOM and tell me with a straight face that all of their corporate in house counsel specializing in intellectual property law are wrong.
        • asveikau 1 hour ago
          I don't know this stuff super well but I imagine it's not necessarily about the lawyers being right or wrong so much as what they can convince people of. The ideal scenario for the patent troll is they can intimidate you into licensing with them. Another good outcome for them (though more costly) is they can convince some non-expert in court. In either case the big players behind the codec can defend themselves but a small one just picking it up downstream as OSS can't.
          • walrus01 1 hour ago
            I don't doubt for a minute that they are going to attempt to intimidate companies using av1 which are much smaller than the AOM founders.
  • tensor 3 hours ago
    Not on topic, but wow the internet has very quickly devolved into: click -> "making sure you're not a bot", click -> "making sure you're a human", click -> "COOKIES COOKIES COOKIES", click -> "cloudflare something something"
    • thresh 2 hours ago
      We had to set it up on the parts of VideoLAN infra so the service would remain usable.

      Otherwise it was under a constant DDoS by the AI bots.

      • nijave 1 hour ago
        While I do sympathetize with the AI DDoS situation, it'd be nice if there were a solution that allows them to work so they can pull official docs.

        For instance, MCP, static sites that are easy to scale, a cache in front of a dynamic site engine

        • thresh 45 minutes ago
          Of course, static websites is the best solution to that problem.

          Our documentation and a main website are not fronted by this protection, so they're still accessible for the scrapers.

      • hectormalot 1 hour ago
        Maybe I’m naive about this, but I didn’t expect AI scrapers to be that big of a load? I mean, it’s not that they need to scrape the same at 1000+ QPS, and even then I wouldn’t expect them to download all media and images either?

        What am I missing that explains the gap between this and “constant DDoS” of the site?

        • thresh 49 minutes ago
          You cant really cache the dynamic content produced by the forges like Gitlab and, say, web forums like phpbb. So it means every request gets through the slow path. Media/JS is of course cached on the edge, so it's not an issue.

          Even when the amount of AI requests isnt that high - generally it's in hundreds per second tops for our services combined - that's still a load that causes issues for legitimate users/developers. We've seen it grow from somewhat reasonable to pretty much being 99% of responses we serve.

          Can it be solved by throwing more hardware at the problem? Sure. But it's not sustainable, and the reasonable approach in our case is to filter off the parasitic traffic.

        • Y-bar 1 hour ago
          They are a scourge, they never rate-limit themselves, there are a hundred of them, and a significant number don’t respect robots.txt. Many of them also end up our meta:no-index,no-follow search pages leading to cost overruns on our Algolia usage. We spend way too much time adjusting WAF and other bot-controls than we should have.
        • nijave 1 hour ago
          I think there's a few things at play here

          - AI scrapers will pull a bunch of docs from many sites in parallel (so instead of a human request where someone picks a single Google result, it hits a bunch of sites)

          - AI will crawl the site looking for the correct answer which may hit a handful of pages

          - AI sends requests in quick succession (big bursts instead of small trickle over longer time)

          - Personal assistants may crawl the site repeatedly scraping everything (we saw a fair bit of this at work, they announced themselves with user agents)

          - At work (b2b SaaS webapp) we also found that the personal assistant variety tended to hammer really computationally expensive data export and reporting endpoints generally without filters. While our app technically supported it, it was very inorganic traffic

          That said, I don't think the solution is blanket blocks. Really it's exposing sites are poorly optimized for emerging technology.

      • nerdralph 1 hour ago
        I highly doubt there is no other technically feasible option to block the AI bots. You end up blocking not just bots, but many humans too. When I clicked on the link and the bot block came up, I just clicked back. I think HN posts should have warnings when the site blocks you from seeing it until you somehow, maybe, prove you are human.
        • goobatrooba 1 hour ago
          I'm sure there are many solutions for many problems, but expecting a small Foss development team to know or implement them all is rather unreasonable.

          I think the world gains more if the VLAN team focuses on their amazing, free contribution to the world, than if they spend the same time trying to figure out how to save you two clicks.

          We all hate that this is happening, but you don't need to attack everyone that is unfortunately caught up in it.

        • overfeed 1 hour ago
          > I highly doubt there is no other technically feasible option to block the AI bots.

          If you have discovered such an option, you could get very wealthy: minimizing friction for humans in e-commerce is valuable. If you're a drive-by critic not vested in the project, then yours is an instance of talk being cheap.

        • thresh 1 hour ago
          I'm all ears on how we can fix it otherwise.

          Keep in mind that those kinds of services: - should not be MITMed by CDNs - are generally ran by volunteers with zero budget, money and time-wise

    • port11 3 hours ago
      The internet is such a Tragedy of the Commons… its citizens that act selfishly and in bad faith will slowly make it unusable.
      • codedokode 2 hours ago
        No, it is because citizen allow treating them like this.
      • esseph 2 hours ago
        > its citizens that act selfishly and in bad faith will slowly make it unusable

        It's rarely been the citizens that have been the problem, but the governments and companies that seek the use the network connection for their overwhelming benefit.

        Re (above):

        > Not on topic, but wow the internet has very quickly devolved into: click -> "making sure you're not a bot", click -> "making sure you're a human", click -> "COOKIES COOKIES COOKIES", click -> "cloudflare something something"

        • fastball 1 hour ago
          wat. The protections in place that the OP is talking about are almost entirely due to (not government and company) bad actors.
      • honktime 2 hours ago
        Its pretty explicitly not a tragedy of the commons. Its a tragedy of the ruling class abusing the resources of the 'commons' to extract value. There is nothing 'commons' about trillion dollar companies extracting all available value from the labor of the working class. That's just the tragedy that'll bring around the death of society, the same tragedy that brings all other tragedys
        • throw-the-towel 2 hours ago
          The commons in question is the internet itself.
        • amusingimpala75 2 hours ago
          Thank you for describing the tragedy of the commons
        • dyauspitr 2 hours ago
          There’s definitely lots of problems with the ruling class and wealth disparity. Perhaps the defining problems of our current age.

          That being said, so many of the plebs suck. Like 2% will ruin everything for everyone.

          • throw-the-towel 2 hours ago
            While a lot of the plebs do suck, a pleb who sucks causes way less problems than a big corp that sucks simply by virtue of not having too much resources.
            • dyauspitr 19 minutes ago
              I agree.

              But whether you agree with me or not, most paradigm shifting changes come from billionaires/corps because they are the only ones with the money to pull off massive shifts. Most innovation is not grassroots and heavily funded by the “elites”. This is how most successful countries have been for atleast the last 100 years. So billionaires add a lot of value even as they cause a lot of pain.

              The solution in my mind is we absolutely need uncapped billionaires but they need to be effectively taxed (not like 90% but closer to 50%) and they have to have absolutely no influence on the government.

    • notenlish 1 hour ago
      Nearly every single website I'm not logged into these days want me to "confirm I'm not a bot".

      it is incredibly annoying but what can you do? AI scrapers ruined the web.

    • pixelpoet 1 hour ago
      No one's even clicking anymore, everything implores me to tap or swipe these days, and everything is optimised for humans with one eye above the other.

      Then I press the X to close the all-caps banner commanding me to install the app, upon which I get sent to the app store. Users of the website refer to it as an app.

    • tomwheeler 52 minutes ago
      At least this one was significantly faster than Cloudflare and required no action on my part.
    • rayiner 2 hours ago
      Wow I’m glad it’s not just me. I thought my IP block had gotten caught up in some known spamming or something.
    • tosti 3 hours ago
      I get exactly none of that. Is your adblocker still working?
    • oybng 2 hours ago
      renders your gigabit connection pointless
  • Telaneo 2 hours ago
    Glorious. Really looking forward to seeing how much better than AV1 it actually turns out to be. It's a shame it'll take a while before we'll have a decent encoder (it took an annoyingly long time until SVT-AV1 was usable).
  • pkos98 1 hour ago
    off topic, but related to the recent github alternative discussion:

    Wow, this gitlab instance looked so much cleaner/simpler and less clunky than my past experiences! Also loaded really fast on first page load as well as subsequent actions

  • risho 44 minutes ago
    is there any understanding of how big of an improvment av2 will be over av1?
  • 0x0 1 hour ago
    Just recently noticed this got posted to deb-multimedia, although I think there is a typo in the package description....

    https://www.deb-multimedia.org/dists/unstable/main/binary-am...

    ... it says "fast and small AV1 video stream decoder"

    ... should probably be "AV2" ?

  • sylware 2 hours ago
    I would even remove the C code and lower the usage of the assembler pre-processor to a basic C pre-processor.

    Happy, AV2 decoding already here.

    :)

  • xnx 3 hours ago
    [flagged]
    • virtualritz 2 hours ago
      And who ever heard of this in the majority of the world? It was news to me, I'm white and European btw.

      Did you know the US consititues about 4% of humans? When we look at adults and age range that likely ever hear of D4vd we are talking probably considerably less that 1%.

      The rest of humanity has no negative association with these four letters.

      • pesus 2 hours ago
        It was my first thought when I saw the name, unfortunately. The US constitutes a large portion of this site's user base. Whether the association sticks around is yet to be seen.
      • DaiPlusPlus 2 hours ago
        > And who ever heard of this in the majority of the world? It was news to me, I'm white and European btw.

        It's a recurring headline on the rolling news channels on broadcast TV right now - and it's on the front-page of Reddit for me as well.

        • Almondsetat 2 hours ago
          So a project should change its name because when it will be production ready 6 years from now the 1% of the 1% of the 1% will think for 1 microsecond about a piece of news from today?
          • Lerc 2 hours ago
            Just that remember that there were people that said calling the second LOTR movie The Two Towers was disrespectful.
          • DaiPlusPlus 2 hours ago
            > So a project should change its nam

            Potentially... supposing the criminal investigation into this uncovers a hitherto unknown organ harvesting scheme operating within the global music records industry; the subsequent police dragnet implicates significant proportion of the world's music stars and record labels and generates continual major headlines and criminal convictions - with all their lurid details - all for multiple decades from now on.

            It's quite ridiculous when I put it that way, but this is basically the same thing as Epstein's network, just with a different crime; and Epstein was already in the news almost 20 years ago from his first conviction.

            ...so back in 2009, back when everyone was building their own social-network websites and online dating services, and supposing your real-name was also Epstein, so you called it "EpsteinLoveIsland.com" - would you have changed the name back then?

        • dingdingdang 2 hours ago
          Gotta admit this was the first thing I thought of as well. Hard to focus on the code implementation with that in mind!
        • encom 1 hour ago
          >news channels on broadcast TV

          So no one below the age of 60 is aware of this.

      • flykespice 34 minutes ago
        > I'm white and European btw.

        Why did you feel the need to explicitly specify that you're white as one of the reasons you didn't hear the news?

        I'm not american either, but the news is all over social media platforms like reddit and Twitter, it's hard to turn a blind eye on them.

    • cosmotic 3 hours ago
      Its a followup to their existing Dav1d decoder (av1, av2)
      • cogman10 2 hours ago
        Which, should be noted, was a thing before d4vd started his career.

        dav1d - started in 2018

        d4vd - started composing in 2021

    • NewsaHackO 2 hours ago
      It's just unfortunate. Like there was a pharmaceutical company named "Isis" that changed their name due to the association with the terrorist group. That said, while people will notice for the next couple of months, I don't think it warrants changing a name for.
    • walrus01 2 hours ago
      By this logic nobody should ever name their child Ted or Theodore because Ted Bundy existed.
  • Zopieux 3 hours ago
    >video decoder implementation

    >look inside

    >it's C

    • tux3 2 hours ago
      Not just C, dav1d and dav2d are actually mostly written in ASM! Then there's a bit of C as the glue or for functions that don't have optimized ASM yet.

      Since dav2d is newer it has a higher fraction of C, but not enough for it to be the main language in the codebase :)

    • Almondsetat 2 hours ago
      What are you even implying?
      • notenlish 1 hour ago
        I think they mean that video decoders and encoders tend to have custom assembly code for speedup.
        • Almondsetat 46 minutes ago
          And? It's common knowledge that the "reference" or "research" version of any codec is always quite high level to get development going and actually produce a working bitstream
      • IshKebab 1 hour ago
        That codecs should be written in safer languages given that they usually process untrusted files. There have been a number of serious hacks from file parsing bugs due to them being written in unsafe languages.

        There's literally a DSL designed for this purpose (Wuffs) so it would be interesting to hear why they didn't use it.

        • brigade 1 hour ago
          There's an order of magnitude difference in speed requirements between file format parsing and image decoding, then another order of magnitude difference to video decoding. Even rav1d reuses dav1d's assembly (most of the actual runtime) to approach its speed.
      • sergiotapia 1 hour ago
        muh rust muh safety muh Safe Code
  • kylec 1 hour ago
    I wonder if the author is a Dave2D fan?

    https://www.youtube.com/@Dave2D

  • dcsommer 2 hours ago
    We must not continue to develop media codecs in memory unsafe languages. Small, auditable sections can opt-out perhaps, but choosing default-unsafe for this type of software is close to professional negligence.
    • fguerraz 2 hours ago
      Cryptography and video codecs are notable exceptions, they put a lot of effort to making the code provably memory safe: no recursion, limited use of stack variables, no dynamic allocations, etc. As a result, memory safe languages bring nothing but trouble by making it non deterministic, that’s especially true for crypto where compiler “optimisations” guarantee you side channels attacks.
    • fishgoesblub 2 hours ago
      Of the 3 software AV1 encoders, the only one that is fully dead is the Rust encoder (rav1e). If people truly wanted memory safe encoders/decoders, they would fund and develop them.
      • vlovich123 1 hour ago
        Fully dead in what sense? Seems like it still has active development to me.
        • fishgoesblub 1 hour ago
          It hasn't had any proper quality/speed improvements in years. Only thing that has changed is updating deps and some bug fixes.
      • esseph 2 hours ago
        > If people truly wanted memory safe encoders/decoders

        Really? How many codecs have your neighbors contributed money for the development of, just curious.

        • computerbuster 54 minutes ago
          I think these conversations are directed by the parties funding the efforts. Example: "we (large company) want a fast AV2 decoder" -> they pay a specialized team to do it -> this team works in C for the most part, so it is done in C. If there were financial incentives to do it in Rust, they'd pay more for a Rust decoder.
        • Telaneo 1 hour ago
          Given Netflix's involvement with SV1-AV1, (not even that) indirectly, at least 1.
    • kllrnohj 1 hour ago
      For the codec itself, the majority of it is performance sensitive and often has a significant amount of assembly even, so a memory safe language doesn't change much.

      However for the container/extractor... those should absolutely be in a memory safe language, and those are were a lot of the exploits/crashes are, too, as metadata is more fuzzy.

      As a practical example of this see something like CrabbyAVIF. All the parser code is rust, but it delegates to dav1d for the actual codec portion

    • maxloh 49 minutes ago
      Decoders written in Rust will be a lot slower than the equivalents in assembly.