Kazam crashed, convert .mux file to .mp4

Question

I was recording a 2+ hour long full screen stream of a game (Company of Heroes) and I stupidly and accidentally closed Kazam before it was complete and to ask me where I wanted to save it.

I have found it's already saved everything to a .mux file (my settings was set so that it converts it as a h264 stream into an .mp4 file)

Since Kazam uses GStreamer, How can I use gstreamer to process it to a playable .mp4 format?

this occurred on Ubuntu 16.04

EDIT: I want to add that I really want to save this video file (need sound included too) a high priority for me.

Answer 1

github.com/bookkojot/mp4fixer   

This tool solves exactly this problem. Worked for me. There are a few simple steps involved, instructions are enclosed. You need a short properly saved video on the same machine with the same kazam to use as input so it knows what the headers should look like. And you get the mp4.