[FFmpeg-user] Naming an audio track

Moritz Barsnick barsnick at gmx.net
Mon Nov 3 12:12:21 CET 2014

[Replying to self]
On Mon, Nov 03, 2014 at 10:21:39 +0100, Moritz Barsnick wrote:
> I do not know, though, whether "name" is a header such as "stco" or
> "udta".

So apparently we're looking as MPEG4/MOV containers here. That's what
Tomáš was using as well, and where I managed to reproduce.

Using AtomicParsley, I managed to "see" that the tag in use is an atom

     Atom trak @ 8193 of size: 560, ends @ 8753
         Atom tkhd @ 8201 of size: 92, ends @ 8293
         Atom mdia @ 8293 of size: 428, ends @ 8721
         Atom udta @ 8721 of size: 32, ends @ 8753
             Atom name @ 8729 of size: 24, ends @ 8753

The atom is described here:

I have found a mention that HandBrake and subler use this atom:

I couldn't figure how to add arbitrary atoms with AtomicParsley, only
how to delete them. I do see ffmpeg has a function named
mov_write_track_udta_tag(), called from mov_write_trak_tag(), called
from mov_write_moov_tag(), but I don't know if it gets used and whether
it does the "right thing" from VLC's point of view, and how to get it
to write the "right thing".

Getting closer,

P.S.: Interesting, because it follows a question I never dared to ask:
      Where does my PVR/STB get the names of its audio tracks from?
      (Albeit MPEG-TS.)

More information about the ffmpeg-user mailing list