• libmp4v2 contains:
    • mp4art - to extract a picture (or coverart from mp4)
    • mp4info - to get meta data from mp4 streams
    • mp4tags - to set metadata and picture.
  • qt-fastload to move index to the front and making mp4 streamable
  • When encoding:
    • Change max GOP or IDR to around 5 seconds.
    • 2-pass avg bitrate: 800 or even 500…

Concatenating files:


ffmpeg has a feature concat, like

ffmpeg -i concat:"video1.ts|video2.ts"

There is also a “concat” video filter that may be useful. See http://ffmpeg.org/trac/ffmpeg/wiki/How%20to%20concatenate%20%28join,%20merge%29%20media%20files


An alternative is gpac. One command it includes is MP4Box to concatenate MP4s

mp4box -cat sbd0.mp4 -cat sbd1.mp4 -new sbd.mp4


Of course the avidemux GUI can append files.

Final notes

So far I have not been able to create a reliable media concat recipe.

Media Gain

mp3gain can be used to normalize volume levels (without re-encoding). Accomplish this by using ReplayGain that needs to be supported by player. (XBMC claims to supports this).