[FFmpeg-user] Adding metadata at the stream level for a multi-stream media file

[Peter White]

Alfredo Di Napoli wrote:
 > Hey guys,
 >
 > Suppose I have a media file composed by 1 video stream and 2 audio
 > streams (both AAC).
 > Is it possible to add metadata at the stream level, for each of the
 > two audio?

It most certainly is. But maybe the answer is that it depends.
Apparently the file format plays a part in this.

 > Here is the command I  tried:
 >
 > ffmpeg-3.1.1 -i multi.mp4 -y -map 0:v -map 0:a -codec copy
 > -metadata:s:a:0
 > title="Foo" -metadata:s:a:1 title="bar" multi2.mp4
 >
 > But the metadata does not show in the output probe:

It is the same for me. I just reproduced this here. But when I use
matroska (.mkv) as output format, it does work.

So, if you are not dependent on mp4 as container format you can at
least work around this. I don't know why it does not work with mp4. I
think it should but I know too little about this format.

 > What am I doing wrong? Is this even possible or am I flogging a dead
 > horse?

Not necessarily a dead but perhaps the wrong horse. ;)


Peter