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Old 19th November 2021, 01:47   #5  |  Link
benwaggoner
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Join Date: Jan 2006
Location: Portland, OR
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Quote:
Originally Posted by RanmaCanada View Post
I refuse to encode anything with noticeable grain, in HEVC. H.264 is still far superior. AV1 is supposed to be better, eventually, but until that happens, I'll just keep remuxing grainy sources and storing the discs on a shelf.
And AV1 isn't intrinsically better. It supports film grain synthesis.

So it's not encoding the grain better, but degraining the source, parameterizing the removed grain, encoding, and putting the parameters into metadata. On playback the degrained frames are decoded and the parameters fed into a grain synthesis filter to generate new grain which hopefully looks like the original grain.

Which is utterly brilliant and should drop bitrates by >50% for grainy content!

But it's not like we've figured out optimal fully automated grain removal and parameterization technology! And that is out-of-band of the actual codec itself, and not something codec engineers are particularly skilled with or interested in. During AV1 development it was largely a "and someone else can implement..." feature. I'm not aware of anyone actually using FGS in deployed AV1 yet.

A cool thing is that the degraining process, metadata, and grain synthesis tech is all codec agnostic. SoC vendors are implementing it generically, so any AV1 decode capable HW should be able to use the same technique with HEVC, VVC, AV2, etc.
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