[Donald Ortiz]"How can i convert mp41 to mp42 with ffmpeg?"
I had a look into this and found that it is an incompatible microsoft variant of mpeg4.
FFmpeg supports these types:
DEVSD msmpeg4 MPEG-4 part 2 Microsoft variant version 3
D VSD msmpeg4v1 MPEG-4 part 2 Microsoft variant version 1
DEVSD msmpeg4v2 MPEG-4 part 2 Microsoft variant version 2
NOTE: the second one does not support encoding
I tried msmpeg4v2 and it created an unplayable file for me... but I am on Mac....
For mov, it reported:
[mov @ 0x7fcd0204d800] Using MS style video codec tag, the file may be unplayable!
For mp4 it failed:
[mp4 @ 0x7fe35c04d800] track 0: could not find tag, codec not currently supported in container
anyway, have a tinker and see if you can get the desired result....