Oh, is more HEVC stuff finally going off patent? They’re the leaders.
AV2 video codec delivers 30% lower bitrate than AV1, final spec due in late 2025
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Re: AV2 video codec delivers 30% lower bitrate than AV1, final spec due in late 2025
#62Earlier quoted context omitted.
Yet I still only got hardware support for it on my first devices last year. The downside of "rapid" iteration on video codecs is that content needs to always be stored in multiple formats (or alternatively battery life on the client suffers from software playback, which is the route e.g. Youtube seems to be preferring).
It'd be really cool if we had 'upgradable codec FPGAs' in our machines that you could just use flash to the newest codec... but that'd probably be noticeably more expensive, and also not really in the interest of the manufacturers, who want to have reasons to sell new chips.
Back in ~2004, I worked on a project to define a codec virtual machine, with the goal of each file being able to reference the standard it was encoded against, along with a link to a reference decoder built for that VM. My thought was that you could compile that codec for the system you were running on and decode in software, or if a sufficient DSP or FPGA was available, target that.
While it worked, I don't think it ever left my machine. Never moved past software decoding -- I was a broke teen with no access to non-standard hardware. But the idea has stuck with me and feels more relevant than ever, with the proliferation of codecs we're seeing now.
It has the Sufficiently Smart Compiler problem baked in, but I tried to define things to be SIMD-native from the start (which could be split however it needed to be for the hardware) and I suspect it could work. Somehow.
Re: AV2 video codec delivers 30% lower bitrate than AV1, final spec due in late 2025
#63It’s pretty amazing people are still finding ways to make video smaller. Is this just people being clever or is it also more processing power being thrown at the problem when decoding / encoding?
It’s more money and more user’s compute being thrown at the problem to get the streaming service’s CDN bill down.
Modern video codecs are what broke the telco monopoly on content and gave us streaming services in the first place. If the cdn bill is make or break, the service isn’t going to last.
And there’s no transfer of effort to the user. Compute complexity of video codecs is asymmetric. The decode is several order of magnitude cheaper to compute than the encode. And in every case, the principal barrier to codec adoption has been hardware acceleration. Pretty much every device on earth has a hardware-accelerated h264 decoder.
Re: AV2 video codec delivers 30% lower bitrate than AV1, final spec due in late 2025
#64It’s pretty amazing people are still finding ways to make video smaller. Is this just people being clever or is it also more processing power being thrown at the problem when decoding / encoding?
Soon we will just have local AI processors which will just make stuff up between scenes but adhere to a “close enough” guideline where all narratively critical elements are maintained but other things (eg landscapes or trees) will be generated locally. Movies will practically be long cutscenes with photorealistic graphics.
Re: AV2 video codec delivers 30% lower bitrate than AV1, final spec due in late 2025
#65Earlier quoted context omitted.
Considering AI is good at predicting things and that’s largely what compression does, I could see machine learning techniques being useful as a part of a codec though (which is a completely different thing from asking ChatGPT to write you a codec)
Yeah in the future we might use some sort of learned spatial+temporal representation to compress video, same for audio. Its easier to imagine for audio: Instead of storing the audio samples, we store text + some feature vectors that uses some model to "render" the audio samples.
It’s not absurd to think that you could send a model of your voice to a receiving party and then have your audio call just essentially be encoded text that gets thrown through the voice generator on the local machine.
AI video could mean that essential elements are preserved (actors?) but other elements are generated locally. Hell, digital doubles for actors could also mean only their movements are transmitted. Essentially just sending the mo-cap data. The future is gonna be weird
Re: AV2 video codec delivers 30% lower bitrate than AV1, final spec due in late 2025
#66Hooray, finally a codec name that doesn't look like AVI
Re: AV2 video codec delivers 30% lower bitrate than AV1, final spec due in late 2025
#67Re: AV2 video codec delivers 30% lower bitrate than AV1, final spec due in late 2025
#68Earlier quoted context omitted.
Yes, and it's allowing the format to change to allow more cleverness or apply more processing power. For example, changes from one frame to the next are encoded in rectangular areas called "superblocks" (similar to a https://en.wikipedia.org/wiki/Macroblock ). You can "move" the blocks (warp them), define their change in terms of other parts of the same frame (intra-frame prediction) or by referencing previous frames…
In general with movement through scenes it would seem that rectangular update windows seem like a poor match. Is there a reason codec's don't use the previous frame(s) as stored textures, and remap them on the screen? I can move a camera through room and a lot of the texture is just reprojectivetransformed.
>Is there a reason codec's don't use the previous frame(s) as stored textures, and remap them on the screen? I can move a camera through room and a lot of the texture is just reprojectivetransformed.
I mean, that's more or less how it works already. But you still need a unit of granularity for the remapping. So the frame will store eg this block moves by this shift, this block by that shift etc.
Re: AV2 video codec delivers 30% lower bitrate than AV1, final spec due in late 2025
#69Earlier quoted context omitted.
I believe patents play a big role here as well. Anything new must be careful to not (accidentally) violate any active patent, so there might be some tricks that can't currently be used for AV1/AV2
I think patents are quickly becoming less of a problem. A lot of the foundational encoding techniques have exited patent protection. H.264 and everything before it is patent free now. It's true you could still accidentally violate a patent but that minefield is clearing out as those patents simply have to become more esoteric in nature.
...till someone decides to patent one of the new techniques used
Re: AV2 video codec delivers 30% lower bitrate than AV1, final spec due in late 2025
#70Will streaming services ever stop over-compressing their content? I have a top-of-the-line 4K TV and gigabit internet, yet the compression artifacts make everything look like putty. Honestly, the best picture quality I’ve ever seen was over 20 years ago using simple digital rabbit ears. You especially notice the compression on gradients and in dark movie scenes. And yes — my TV is fully calibrated, and I’m paying for…
Seems like piracy is the way for you
Sadly many shows aren't released on BluRay anymore, so even piracy won't deliver better quality.