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lukevp

For others like me who are curious and haven't heard of AV1, some main features:

* Open & Royalty Free (no licensing required to use)

* Backed by Mozilla, Google, Microsoft, Cisco, etc. [1]

* Approximately 50% higher compression than x264 [1] and 30% higher than H.265 (HEVC) [2]

* Supported in current versions of Chrome, Firefox, Opera, and Edge [3]

* Slower encoders than HEVC, so not typically used for live streaming [2]

[1]: https://en.wikipedia.org/wiki/AV1

[2]: https://www.theoplayer.com/blog/av1-hevc-comparative-look-vi...

[3]: https://caniuse.com/#feat=av1

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Note that the encoders are slower largely because it's not hardware-accelerated yet.

We can reasonably assume that will change, as basically every major player in the CPU/GPU spaces[1] has signed on to back this. Even Apple is a member.

[1] the exceptions are mostly downstream ARM vendors - notably, Qualcomm

> Note that the encoders are slower largely because it's not hardware-accelerated yet.

This is a very misleading statement.

AV1 encoders are slow because they're slow, not because they're not hardware accelerated.

x264 and x265 are not hardware accelerated, either.

> x264 and x265 are not hardware accelerated, either.

This is incredibly false.

https://en.wikipedia.org/wiki/Intel_Quick_Sync_Video

https://en.wikipedia.org/wiki/Nvidia_NVENC

https://en.wikipedia.org/wiki/Video_Coding_Engine (this has been widely available for 8 years)

You've linked competing hardware encoding APIs which are not x264/x265.

x264/x265 are software encoding libraries for H264/H.265 video formats and don't really use hardware acceleration beyond SIMD instructions on CPUs. x264 is known for its great output quality while still being fast on x86 CPUs.

I think kasabali was talking about x264 (https://www.videolan.org/developers/x264.html) and x265 (http://x265.org/) specifically rather than the H.264 and H.265 video formats in general.

x264 and x265 refer to the specific set of software programs of the same name, right? Most chips nowadays can hardware accel H.264 and H.265, but they don't use x264/x265 (or do they? Not sure...). I think the confusion is that the terms x264 and H.264 are not interchangeable

> x264 and x265 are not hardware accelerated, either.

Huh, TIL.

Though I would also sort of want to know where x264 and x265 were a year in, tbf.

Still no support in any mobile browser. 35% isn't a lot of coverage. And of course Safari is a holdout -- they haven't even adopted VP9 yet.

> And of course Safari is a holdout -- they haven't even adopted VP9 yet.

Given Apple is an AOM governing member it's pretty likely Apple will eventually support AV1 (and AVIF).

VP9 is simply not on their roadmap at all, it's not a "yet" thing.

and they never will - apple is not interested in vpX codecs. AV1 is different story.

As far as I know, WebM only recently added AV1 support to its container format. Before that, it was already supported in MP4 and Matroska.

Thanks, I removed the reference to WEBM in that case. MP4 and MKV are very common container formats, so being supported in WEBM, MP4, MKV doesn't seem like a differentiator.

With how versatile the MKV container is, it seems odd that it isn't the de facto container out there.

Not to mention WebM is (was?) literally a subset of Matroska.

Afaik WebM is just a royalty-free subset of MKV, maybe with some exotic features omitted.

>WebM only recently added AV1 support to its container format

I was unable to find any evidence of this anywhere I looked. For instance this webpage: https://www.webmproject.org/docs/container/ shows only VP8 and VP9 as acceptable video codecs.

Indeed you are right, my mistake! While ffmpeg allows writing AV1 streams to WebM containers, it's not officially supported by the spec. I'd be interesting to know whether Firefox and Chrome support playback of these WebM AV1 streams though.

>ffmpeg allows writing AV1 streams to WebM containers

Any idea why they flipped the switch on that? Seems irresponsible when .mkv will do in all circumstances.

AFAIK even HEVC isn't typically used for live streaming, at least not on Web (YouTube, Twitch, etc.).

Is there any examples of major services currently using HEVC?

Apple Facetime. Netflix 4K on select TVs.

Most commercial 4K content, e.g. pretty much all 4K television broadcasts. YouTube/Twitch don't like it due to the royalties.

>Approximately 50% higher compression than x264 [1] and 30% higher than H.265 (HEVC)

What is the relative improvement between codec generations (e.g. H.264 vs. H.265) compared to implementations of the same codec standard (e.g. early reference implementation of H.264 vs. current x264 with well-chosen parameters)?

I recently did some encoding, but settled on VP9 over AV1 because it has wider support and ffmpeg considers its encoder "experimental." VP9 is supported out-of-the-box on practically everything modern that isn't Apple. AV1 is on-track to replace it, but depending on the support you're looking for, that might be five years out.

I downloaded Blade Runner 2047 in AV1 (search for `av1` in qbittorent), tiny size and it looked fantastic! I can't wait until more releases are made with this codec. Youtube will save a ton of money and people on networks like Ting will be able to stream content and not pay ridiculous amounts of money.

You obviously meant 2049 (unless there's a much more compressible pre-montage version of the movie 2 commits before the final version, that is :) )

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