Add support for AV1 streaming with Enhanced RTMP

[Conan-Kudo]

Describe the problem to be solved

It should be possible to stream to PeerTube using open, royalty-free codecs like AV1 rather than using encumbered codecs like H.264.

Describe the solution you would like

Now that the Enhanced RTMP specification is available and OBS Studio implemented support for it in v29.1, PeerTube should implement support for the new spec so that OBS can stream in AV1+Opus to PeerTube.

[Chocobozzz]

Hi,

As an information we use https://github.com/illuspas/Node-Media-Server to handle RTMP streams, and ffmpeg to mux/transcode it to HLS.

Does ffmpeg support enhanced RTMP?

[Conan-Kudo]

There's a patch set by @T-bagwell to add this capability to FFmpeg under review. I'm optimistic that it'll land soon. 😄

[Conan-Kudo]

This is all now available with FFmpeg 6.1.