This is set to use mp4mux, but I actually normally use matroskamux because
the file remains playable even if you don't finalize correctly (i.e. if
program crashes, you can play what was recorded). This uses a videotestsrc,
but I don't think that makes much of a difference, should be easy to
Re: mp4mux with h264 stream from appsrc - Could not multiplex stream.
You're probably right, I messed around a bit for my own education. Attached
is sample code, tested on the Jetson Nano. You can probably run it on
anything; just change out the hardware-specific elements with