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AV1 video codec gains broader hardware support

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Re: AV1 video codec gains broader hardware support

#71

I don't know what's up with AV1 software decoding but it uses considerably more CPU than HEVC or VP9

AV1 is more complex. Prediction can be more complex with things like "combined inter/intra" or "warped motion" or "overlapping block MC" compared to HEVC/VP9. Then there's additional postfilters like loop restoration, cdef and film grain that didn't exist in VP9 (just deblock - which also exists in AV1) or HEVC (deblock + sao). Entropy coding is more expensive than VP9 with per-symbol entropy updates (which HEVC also has). Bigger blocks are probably an overall win, but bigger transforms can be painful with many non-zero coefficients. And intermediates in 2D MC and bi-directional ("compound") prediction are 12-bit instead of 8-bit in VP9 for SDR/8bit video. This is more similar to HEVC. So overall, AV1 > HEVC > VP9 in terms of runtime complexity, this is expected, nothing you can do about it.

Re: AV1 video codec gains broader hardware support

#72
post #12

I would add that broader AV1 support is also a good news for low latency application like Cloud gaming or streaming to VR headsets. HW accelerated encoding/decoding improve upon HEVC on every metrics so you can get near real-time streaming with higher quality and lower bandwidth requirements.

This doesn’t match up to my experience playing on Quest 3. Certainly I see better quality for lower bandwidth, but the client side decoding actually adds more latency at the point it actually looks better the HEVC.

Re: AV1 video codec gains broader hardware support

#73
post #48

According to the article, it's supported by every browser except Edge. It will be interesting to see who ultimately ends up making a better IE, Safari or Microsoft. So far, it seems Safari is winning, given the ever growing set of standards they don't support, but maybe this is Edge trying to catch up?

[flagged]

Because they want something less user hostile than Chrome?

Re: AV1 video codec gains broader hardware support

#74
post #29

Earlier quoted context omitted.

In context of format war, winning means that they earn patent fee from every device. I don't think it's Apple's intension, but possibly Qualcomm's.

Qualcomm isn't even a part of the HEVC alliance patent pool, so that theory doesn't hold. Indeed, the fact that Qualcomm is currently building AV1 support into their next chip (purportedly) puts them at risk of being sued because while AV1 is open, we all know how patents work and there are almost certainly actionable overlaps with the pool. Apple ships probably more devices than anyone, and given that the patent poo…

If I'm not wrong paying to patent pool is capped, so apple would just pay at the cap

Re: AV1 video codec gains broader hardware support

#76
post #31
post #12

I would add that broader AV1 support is also a good news for low latency application like Cloud gaming or streaming to VR headsets. HW accelerated encoding/decoding improve upon HEVC on every metrics so you can get near real-time streaming with higher quality and lower bandwidth requirements.

> improve upon HEVC on every metrics Color me the skeptic here, but which benchmark(s) are we talking about? Even h264 vs h265 is not a settled matter - if we truly consider every possible metric, including e.g. SW encoding.

I'm interested as to why it isn't a settled manner. In my experience, H265 files tend to strike really nice compression ratios (in the same vein, after an AV1 transcode, I'm typically left gobsmacked).

(Or were you talking more about latency? In that case I have to defer to someone with more knowledge.)

Re: AV1 video codec gains broader hardware support

#77

How much silicon does it take to add an AV1 decoder to a chip? The areas Apple highlighted in their A17 release looked pretty substantial, but I wasnt sure if it was to scale. https://b3148424.smushcdn.com/3148424/wp-content/uploads/202...

That looks like a pure marketing slide to me. I don't think it would make sense to actually have separate dedicated silicon for these.

How would you do it in hardware otherwise?

Re: AV1 video codec gains broader hardware support

#78

According to the article, it's supported by every browser except Edge. It will be interesting to see who ultimately ends up making a better IE, Safari or Microsoft. So far, it seems Safari is winning, given the ever growing set of standards they don't support, but maybe this is Edge trying to catch up?

What are the "ever growing set of standards" that Safari doesn't support?

Nothing that is relevant. I use safari across all my devices and I have never had an issue besides very specific things like flashing microcontrollers through a web interface which I had to use chrome for. That’s basically irrelevant for the entire world. Safari is mega efficient and fast and actually cares about your privacy

Re: AV1 video codec gains broader hardware support

#79

Earlier quoted context omitted.

Microsoft Edge USED to support AV1 through the extension, but decided to disable the support altogether since v116. The "Can I use" website [1] has the up-to-date information on this. [1] https://caniuse.com/av1

Huh, I didn't know that, good point! Even weirder though. Hopefully it's a prelude to built-in support.

This can be treated as a rumor but I heard a Microsoft developer on Mastodon hint that they had been having trouble with a patent troll, so maybe that's the reason behind the kind of obnoxious workaround too. But that they were dealing with it.

Re: AV1 video codec gains broader hardware support

#80

I don't know what's up with AV1 software decoding but it uses considerably more CPU than HEVC or VP9

It looks like dav1d is (or was 2 years ago, maybe it's even faster now) on par with ffmpeg's hevc decoder in that aspect: https://youtu.be/wkZ4KfZ7x1k?t=656

You're right about VP9 though, definitely faster to decode, though there are trade-offs (video quality, encoding performance) when compared to HEVC.

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