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Comment by brucethemoose2 | Hacker News Reader

The hardware encoders are very fast and generally better than x264 (but not by as much as you'd think with the x264 slow preset).

In addition, there are fast threaded AV1 encoders you may be overlooking, like SVT-AV1. For non-realtime, my favorite is av1an, which also yields better quality than is possible from aomenc and works with pretty much any encoder/codec: https://github.com/master-of-zen/Av1an

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Hardware encoders are fine for streaming but not archiving. A CPU encoder can produce a file that is half the size or less for the same quality.

Yes, but AV1 hardware encoding beats x264 software encoding, if thats the only other option (albeit not by much).

Do you have a way to reproduce this?

This comparison is not mine, and its excellent:

https://giannirosato.com/blog/post/nvenc-v-qsv/

x264 used the medium 10 bit preset, which is a bit of an oddball because 10 bit AVC is "unofficial," and many hardware decoders don't support it.

The benchmark should be against x265 though, which is mainstream now

Is it? AFAICT most things are still on h264.

Most things where? Like, the biggest video app on the earth called Youtube uses mostly VP9/AV1 (it will only play H.264 if you don't have any encoding for VP9 OR AV1, which is very, rare).

Netflix also uses H.265/AV1. Amazon, HBO, Disney, etc also use H.265, but I believe only on higher resolutions.

On Apple world even phone pics uses HEVC (HEIC).

I think it's a total mix honestly (Because tiktok/X/Meta uses h264 as far I know).

Most things like the rest of the world - H.264 is really the only option.

More technically correctly, more than half the currently in use devices in the world do not support more than H.264

Like all my Smart TVs, my kitchen iMac, my parents’ phones etc. only my phone and my laptop support HEVC.

They force AV1 and VP9 via software decoding even if your hardware doesn't support it. Youtube been using VP9 for a decade, even without HW support at the time.

Netflix uses AV1 when on mobile data, even if the HW doesn't support as well (for TVs, it need HW decoding).

The only way to not use VP9 on Youtube is if you don't have the codec installed, which is super rare because the codec is open.

x264 opponents are earlier versions of AV1, namely VP8 and VP9.

x265 should be what is compared against AV1 when discussing quality and encode speeds.

We use x264 for compatibility purposes, if your device is intended to play video, it will decode x264. x265 decoders are in a lot of devices at this point, and AV1 is just now starting to see representation.

x264 is like .jpeg and will probably never die.

Yeah y'all are preaching to the choir, but AVC is still the default for... Well, everything, including OP.

It will probably eventually be like mp3, where users are still reflexively encoding to it without a good reason.

Unlike mp3s compared to other audio codecs, h264 has the luxury of pretty much ubiquitous support for hardware decoders and encoders against other video codecs, so I believe it will have an even longer life than mp3.

A nitpick: x264 is an encoder implementation, the format itself is called H.264 (and H.265).

av1an is essentially a "wrapper" around other encoders. I've played around with it lot in the past, but have never seen any real quality gains from using it (as measured by VMAF) instead of just using the encoder directly. Am I doing something wrong? What exactly does av1an buy me (except maybe for better independent threads?)

First some background. Av1an works by splitting videos into scenes/chunks, which it then encodes in parallel. But this also allows it to change encoding settings for each scene.

Specifically, it has a "VMAF target" mode that encodes a few frames from each scene as samples, measures their VMAF, and then boosts or reduces the encoding preset for that individual scene based on the result. It also has a "black boost" feature to allocate more bitrate to dark scenes, which encoders and various metrics tend to misrepresent.

Also, the possibilities with the VapourSynth support are infinite. Some simple examples include denoising a noisy video on the GPU for better quality than the encoders' CPU denoising, or deblocking with custom parameters, or upscaling with some model in PyTorch. And that's just the start:

https://vsdb.top/

There's a feature that allows you to try and target a specific VMAF score, but it doesn't work very well. What av1an does do for you is increase the speed by a lot, especially for aomenc and rav1e, which don't scale well with high thread counts. SVT-AV1 doesn't really have this problem.

A faster encode might allow using a slower speed/preset setting, which would increase quality per bitrate a little bit. But I don't really consider av1an a tool that increases encode quality, to be honest.

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