Add local ffmpeg and MediaMTX builds to Docker

[j0sh]

This is needed in order to support Opus (enhanced RTMP) for audio pass through.

The MediaMTX changes have been submitted upstream; hopefully they will get merged soon and we can go back to using off the shelf releases.

[hjpotter92]

since this is temporary, should we put the removed snippet as comments instead of deleting completely?

[hjpotter92]

and update the MEDIAMTX_VERSION with v1.11.2-livepeer-1 as we track that version field for alerts in deployments/version mismatches.

[mjh1]

I'm ok with still deleting, we have the git history to go back to. not really a big fan of commented out code

[j0sh]

Re-introduced the MEDIAMTX_VERSION env var in d6d05ed

since this is temporary, should we put the removed snippet as comments instead of deleting completely?

I am not sure exactly how temporary it would be ... depends on how soon our changes get upstreamed, and whether there is anything else we need to change and maintain for ourselves. Could be a while. Like Max said, we have the git history to fall back to.

[mjh1]

I thought we already had local ffmpeg for rtmp input and output 😕
https://github.com/livepeer/go-livepeer/blob/master/media/rtmp2segment.go#L59

[mjh1]

Oh I see now, you've removed the apt install and are compiling it instead

[j0sh]

Yes - the system ffmpeg is quite old (version 4-something) and we need the bleeding edge, since ffmpeg's support for Opus in RTMP was merged just a couple weeks ago

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 1 line in your changes missing coverage. Please review.

Project coverage is 32.25330%. Comparing base (86922ea) to head (7206957).
Report is 1 commits behind head on master.

Files with missing lines	Patch %	Lines
server/ai_mediaserver.go	0.00000%	1 Missing ⚠️

Additional details and impacted files

@@                 Coverage Diff                 @@
##              master       #3353         +/-   ##
===================================================
- Coverage   32.25409%   32.25330%   -0.00079%     
===================================================
  Files            147         147                 
  Lines          40584       40585          +1     
===================================================
  Hits           13090       13090                 
- Misses         26723       26724          +1     
  Partials         771         771                 

Files with missing lines	Coverage Δ
media/mediamtx.go	0.00000% <ø> (ø)
server/ai_mediaserver.go	7.38832% <0.00000%> (-0.01271%)	⬇️

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Files with missing lines	Coverage Δ
media/mediamtx.go	0.00000% <ø> (ø)
server/ai_mediaserver.go	7.38832% <0.00000%> (-0.01271%)	⬇️

[j0sh]

Updates for a6e7aef

Updated MediaMTX to latest + bumped Livepeer git tag to fix this issue: bluenviron/mediamtx#4212

Also had to lowercase the connection type since MediaMTX changed these strings recently: bluenviron/mediamtx#4076 Lowercasing keeps us compatible across versions. cc @mjh1