Implement rav1eenc.c for libavcodec

[Kagami]

This issue rather belongs to ffmpeg's bugtracker but I suppose it would be useful to have tracking issue here as well.

Right now ffmpeg supports encoding to AV1 only via libaom. Would be nice to add encoding support via rav1e as well.

[lu-zero]

A C API is in the work, it depends on #410 and wouldn't be limited to libavcodec. :)

[tdaede]

This is especially useful because ivf to mp4 muxing in ffmpeg doesn't currently work due to the lack of an av1 parser.

[kodawah]

this is on my todo plate for march

[farindk]

+1 from me.
I started an AV1 plugin for libheif in order to support AVIF images (https://github.com/strukturag/libheif).
Since libaom is way too slow, I would like to use rav1e instead, but I depend on a C API for that.

[lu-zero]

The C API exists, you are welcome to use it and provide feedback :)

[farindk]

Thanks for the link. I will have a look.

Offtopic question: is there support for encoding with still_picture and reduced_still_picture_header set in the sequence header?

[tdaede]

We're missing an API call to set it. When that's added, still_picture should work. There's also some support for reduced_still_picture_header but it's never been tested so we may need to fix a few bugs.

[farindk]

Sounds good. As soon as I find some time, I'll try to integrate rav1e to libheif.

[dwbuiten]

WIP: https://github.com/dwbuiten/FFmpeg/tree/rav1e

[xuguangxin]

@dwbuiten , any update on this? I want to use ffmpeg+rav1e to do some RD curve comparison. Is your patch ready for target bitrate setting?
thanks

[lu-zero]

@xuguangxin what do you have in mind?

[dwbuiten]

@xuguangxin It's a few extra lines of code to update the patch to properly map bitrate options from FFmpeg to rav1e.

However, rav1e's bitrate mode is a WIP. I am, in fact, working on updating some of the empiracally derived values in the bitrate RC code to work properly with AV1 (one of tons of low hanging fruit for rav1e).

If you really want to test it within FFmpeg, you can apply the patch as-is and build; it will work fine, but you have to specify stuff like bitrate via -rav1e-params quantizer=<maxqaunt>:bitrate=<bps>.

[xuguangxin]

@lu-zero , just want to draw some RD curve for all AV1 encoders and compare it with x264 and x265. But current rav1e's ivf muxer did not write bitrate information to headers.

@dwbuiten. I had use some workaround to get the bitrate. I used ffmpeg remux the ivf to mp4. ffmpeg will calc the bitrate for me.
I got the basic RD curve now. As you said, seems rav1e's bitrate control still WIP.

Also, I want to double confirm you with params. To make sure I did not make a mistake.
Here is command for one pass abr:

encoder	params
x264	ffmpeg -i $INPUT -c:v libx264 -tune psnr -b:v $RATE -bufsize 2*$RATE -vframes 600 $OUTPUT
x264	ffmpeg -i $INPUT -c:v libx265 -tune psnr -b:v $RATE -bufsize 2*$RATE -vframes 600 $OUTPUT
libaom	ffmpeg -i $INPUT -c:v libaom-av1 -b:v $RATE -bufsize 2*$RATE -vframes 600 $OUTPUT
rav1e	rav1e --tune Psnr -b $RATE $INPUT -o $OUTPUT

thanks for help

[Kagami]

Offtopic, but can't you get bitrate just by diving file size to the number of seconds in resulting video which should be known in your case?

[xuguangxin]

Sorry for off topic :). In this case, I need query fps and frame count from ivf. Then to the calc by my self. But ffmpeg can help me do this :).
Just need one line, "ffmpeg -i out.ivf -c:v copy out.mp4 && ffprobe -v error -select_streams v:0 -show_entries stream=bit_rate -of default=noprint_wrappers=1 out.mp4"

[dwbuiten]

This is done an upstreamed.

[peters]

FFmpeg/FFmpeg@d8bf244