Viewing contents of GoPro `udta` atom/box with mp4dump?

[victorhooi]

I'm trying to understand some of the data in GoPro MP4 files. They normally have a udta box/atom (hopefully I'm using the right terminology here) that has some camera metadata in it, and other global metadata for that video.

I am able to use the Bento4 mp4dump utility to view the structure of the file, including the udta box, and the fields in it, and I assume their sizes:

~/code/Bento4/cmakebuild/mp4dump GX010870.MP4
[ftyp] size=8+12
  major_brand = mp41
  minor_version = 20131018
  compatible_brand = mp41
[mdat] size=16+10582934258
[moov] size=8+1248744
  [mvhd] size=12+96
    timescale = 24000
    duration = 33809776
    duration(ms) = 1408741
  [udta] size=8+26381
    [free] size=8+22
    [FIRM] size=8+15
    [LENS] size=8+16
    [CAME] size=8+16
    [SETT] size=8+12
    [MUID] size=8+32
    [HMMT] size=8+404
    [BCID] size=8+36
    [GUMI] size=8+16
    [GPMF] size=8+25600
    [free] size=8+124
...

But I can't seem to find a way to view the actual data in those fields?

Is there some way to do that with mp4dump? Or is there a different tool in the Bento4 suite that I should be using for that?

[barbibulle]

One option here is to use the mp4extract tool to save each entry to a file.
Ex: mp4extract --payload-only moov/udta/FIRM input.mp4 FIRM.bin.

[legosoff]

Oh, you're finally alive barbibulle.