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What's the state of the art AV1 encoder right now? Is it practical to encode hours-long videos on regular personal computers now?

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I use either aom for trying to make "optimized" encodes of things to get quality at the smallest file size or svt for fast encodes that aren't really any more efficient than h265, just with the better codec.

I just transcoded some movies with vmaf of 98% from 4k hdr blurays this last week. Takes about two days of mostly single core work with cpu-used=4 on a 5950x but they get average bitrates of around 4400 kbps. Which is like, really, really good for hitting that quality target.

The trick is that since its mostly single core I just do 16 movies at a time, or 24 on my server.

I was like "wtf is vmaf?!"

Turns out it's $NFLXs OSS automated encoding quality assessment tool. Pretty cool!

https://github.com/Netflix/vmaf

p.s. zanny, nice casual stealth drop you did there ;)

I have no affiliation with Netflix, I just like using av1an which supports vmaf quality targets.

If Netflix wants to hire me, dm me, lol.

Best way to encode video is to use a scene detect algorithm to chunk up the video into multiple parts, configure your encoder to encode those parts with a single CPU thread, and spin off one thread per scene to your CPU's max amount of threads. You then just concat the scenes together afterwards.

For anyone actually wanting to do this, Av1an handles all of it automatically for you.

https://github.com/master-of-zen/Av1an

SVT-AV1 has massively improved encoding speed. I was getting ~4x encode speed with some heavy compression (barely any noticeable quality drop) on 1080p/24fps footage on my Ryzen 7 3700X just yesterday.

4x means that you can encode with 1/4 the time of the video, right? That sounds nice, a lot more practical than when I tried before.

To get a rough idea - is it faster or slower than HEVC encoding on a CPU (without any hardware encoder)?

https://www.spiedigitallibrary.org/conference-proceedings-of...

It's good and getting gooder.

Just give it a try using https://github.com/Alkl58/NotEnoughAV1Encodes or whatever, svt-6 is fairly quick.

For cpu I don't know but h265 hardware acceleration ASICs are mainstream contrary to AV1. Also h265 can reach higher compression level than AV1 although the difference is relatively small apparently. However technologically AV1 is largely obscolete since h266 stable has been released.

Every study I've seen shows AV1 beats H.265 on VMAF at all bitrates. H.265 never got significant browser support, and I don't expect H.266 to either. https://caniuse.com/hevc

I have seen a scientific paper a few weeks ago stating h265 was ~7% smaller than av1 on tested dataset. Although maybe it's dataset sensitive or differ because of the metric? (maybe it was PSNR or SSIM?) Anyway any data on AV1 hardware decoding energy consumption vs h265? That is probably the main differentiating metric of interest here

svtav1 is the best I've found, personally. Unlike libaom, it's parallelized, which obviously helps massively. I use it at quality profile 20 (as given to ffmpeg params), but I'm not an expert here.

There is also https://github.com/xiph/rav1e

If you want quality your choice is still limited to the reference encoder libaom.

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