https://forums.linuxmint.com/viewtopic.php?t=391549
The symptoms described (audio but no video) are the same as the issue I had: [viewtopic.php?t=391549]
(SOLVED: GStreamer plays only audio for MP4 videos on Mint 21.1 - Linux Mint Forums). It was caused by a problem with the accelerated video codec in GStreamer, and can be worked around by an environment variable.
As stated above, VLC has its own codecs, so doesn't suffer from the problem.
It seems not to be missing codecs.
Maybe you can figure out what this means eric, it is way beyond me.
GStreamer selects codecs based on capability and priority. The priority of a codec (0 - 255?) can be manipulated via the GST_PLUGIN_FEATURE_RANK environment variable. By launching my app from a shell script that set the variable, I was able to work around the problem:
Code: Select all
GST_PLUGIN_FEATURE_RANK="vaapidecodebin:0" python3 ...
I hope this write-up helps someone else grappling with the issue...