Joshiraku VS SVT-AV1

- <https://github.com/Kaleido-subs/Joshiraku>

Regarding 'why' AV1 and other codecs like VP8/VP9 or VVC haven't really been used:

1. Many of the private trackers have fairly strict rules in terms of standards (e.g., due to lack of hardware support, perceived differences in quality, etc., many don't allow <4K HEVC encodes at all, except in edge cases like when a streaming platform releases a new show in HEVC-only), so individual encoders and groups aren't always free to use whatever codecs they please.

2. Many seem to find x264 easier to tune for certain types of media than x265, and even more so compared to AV1 and others.

3. Many seem to believe that insert codec tends to produce worse results in certain circumstances or for certain content, so they will stick with x265 (or even x264 for the same reasons)

4. Many find that, to truly achieve the same picture quality produced by x265, compression ratios often end up much worse than people claim, and thus the significant slow-down in encoding speed and loss of hardware support is not worth the minor reductions in size.

#4 is likely the most common reason, as it was/is the same with those who prefer x264 over x265; HEVC video is definitely not "half the size" if you want it to look comparably good. And so, especially in the past with older hardware, it simply wasn't worth the tradeoffs; it's worth remembering that, in the case of piracy groups which distribute over P2P networks, no one is paying a AWS exorbitant amounts of money per terabyte of data transferred.

These sites run off of 'free' bandwidth provided by users and cheap unmetered servers from companies like Hetzner, OVH, LeaseWeb, etc -- saving 10-30% in bandwidth often is not worth it at the expense of doubling your encode times (or significantly worse than doubling, in the case of AV1 and VVC) and alienating the people watching on older hardware.

The docs mention that the unit for this option is in "frames" (not "seconds").

From the pull request:

In these tests SVT-AV1 beats x265 on quality:

- FullHD: http://compression.ru/video/codec_comparison/2022/main_repor...

- FullHD 10-bit: http://compression.ru/video/codec_comparison/2022/10_bit_rep...

- 4K: http://compression.ru/video/codec_comparison/2022/4k_report....

SVT-AV1 has seen a number of speed ups in recent releases:

https://gitlab.com/AOMediaCodec/SVT-AV1/-/releases

I don't see this options under the "Advanced features" like for H.265/HEVC (for example). Also, adding "-input-depth 10" manually to the command line doesn't work (it doesn't recognize the parameter, despite it clearly being written here as one of them).

Docs for SVT-AV1 at https://gitlab.com/AOMediaCodec/SVT-AV1/-/tree/master/Docs

I find it interesting that you know the project well enough to get to the pre-compiled binaries page, yet somehow missed that the merge request explictly calls out a VMAF LOSS for the SSIM tune by several percentage points.

SVT-AV1 has no NEON.

I used the precompiled FFmpeg from SVT-AV1's git: https://gitlab.com/AOMediaCodec/SVT-AV1/-/jobs/4540276837