This is a reduced test case of an issue I've been encountering with pion and H264 streams.
When reading VP8 video from a file descriptor and sending it to a client over WebRTC, the video starts instantly.
When reading H264 video from a file descriptor and sending it to a client over WebRTC, the video doesn't start for 8 seconds (and starts 8 seconds in).
./build.sh will build a docker image and ./run.sh will run it. Or if you already have go and ffmpeg installed, then just compile the .go files and use ./boot.sh.
Then go to http://localhost:8080 to view the page. You should see the ffmpeg testsrc pattern.