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Joined 3 years ago
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Cake day: August 15th, 2023

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  • Yeah as a result of this post I decided to look into AV1 grain synthesis again. That’s the only way I can see that AV1 can meaningfully “improve” over h265 right now for noisy content like movies, which is what enthusiasts care about.

    Grain synthesis is where you analyze noise on the original file, denoise the video stream and reapply artificial noise of a similar style as the original at decode time.

    It relies on a lot of assumptions:

    • The denoise doesn’t kill your quality
    • The grain synthesis looks convincingly like real film grain.
    • decoding devices will support rendering the grain

    From a short experiment, I found that VLC was able to render the synthetic grain, but MPV(.net) did not out of the box. I had to play around with gpu rendering modes to get it to work.

    As for transcoding, it’s unclear what happens to the synthetic grain, whether it is burnt in or simply ignored. At least one or two people have reported it will just be ignored and you’ll get a weirdly smooth movie.


  • Typical end users do not. Companies do because it will save them money.

    Enthusiasts will care because it could save them storage space for equivalent quality, though if the cost of encoding is so high then just in terms of energy costs you may save money just going for a cheaper codec and upgrading storage with the saved money.






  • I use VBR and adjust the quality slider until I cannot see artifacts. I don’t do anything particularly special and maybe there’s more that could be done.

    I once heard of an approach where you remove all grain and reapply it live to reduce the bitrate. That sounds interesting but denoising usually results in quality loss and it will likely look pretty artificial. My tooling also does not support it, so I’ve not bothered.

    If someone can recommend me a good encoder or tool I can try that is better than whatever comes with handbrake I’m happy to give it a go.


  • Having tried AV1, I found that it was worse than h265 for what I use it for: high quality movie encodes.

    It doesn’t preserve grain well, and if struggles with maintaining quality in low light scenes.

    On top of all of this it tends to be more CPU intensive than h265.

    For this testing, I used Handbrakes CPU encoder.

    I realise that this is maybe not what AV1 is intended for. It’s probably best suited to making low bitrate streams more tolerable. Maybe AV2 will be better 🤷



  • The full translation of the clip of Gaël Duval provided by GrapheneOS:

    There’s the attack surface, on that front we’re not security specialists here, so I couldn’t answer you precisely, but from the discussions I’ve had, it seems that everything we do reduces attack surface.

    However, we don’t have a “hardened security” approach, we aren’t developing a phone for pedo(censored) so they can evade justice. So there aren’t difficult things to check if the memory is corrupted, really hardened security stuff that could clearly be useful for executives, in the secret service, or whatever.

    That’s not our goal, our goal is to start from an observation: today our personal data is constantly being plundered and that wouldn’t be legal in real life with the mail or the telephone, we want to change that. So we are making you a product that changes that by default for anyone.

    As a french speaker, I can attest that the translation is fairly accurate.

    While I don’t agree with the characterisation Gaël Duval makes here, I believe the statement from GrapheneOS here:

    Duval and his organizations have consistently taken a stance against protecting users from exploits. In this video, he once again claims protecting against exploits is for only useful pedophiles and spies.

    Is a bit disingenuous. It sounds like they do make some efforts to secure their device, but it’s not their main focus. Theirs is to improve privacy first and foremost.

    I would take anything GrapheneOS devs says with a grain of salt, as we all know that they have quite an adversarial relationship with… well… everyone. But especially other OS makers.






  • Whoever promised that?

    Updated the description to clarify.

    The economic incentive from Signals point of view is that it allows them to steal users. Its a lot easier to switch if you don’t have to drag 100% of people you know off a platform to remove their app.

    Look up adversarial interoperability if you’re interested. It’s how Facebook got big in the first place.

    As for Meta, the only thing they would gain is less scrutiny from regulators as Gatekeepers.





  • Made the jump last week.

    The only thing I miss is Android Pay, but it’s not a big deal. Cards are fine, you’ll just need to remember your wallet.

    I did find I had a problem with my work 2FA app, but that’s their problem to solve, not mine. Maybe they’ll give me a 2FA USB key.

    A few pieces of advice:

    • Don’t forget to back up any apps with local data that support it. You won’t get your app data back from the play store. Many FOSS apps have built-in backup optioms to files etc.
    • Back up your phone logs and SMS if that’s valuable to you, and ideally make sure the backup works on another device.
    • Install GCam to keep the same level of camera quality and features as the original app provides. I recommend BigKaKa’s versions for good compatibility with Pixels, though they can get a little cluttered.
    • Do install both the Play Store and Play Services if you want to use any Google app like YouTube or Maps (even some non-Google ones will need it). Then use a more private app store like Aurora and remove all permissions from the Play Store to strike a good middle-ground.
    • The Fossify apps are great alternatives to the imo not very good stock apps preinstalled on LineageOS.