"Trying to add item, but missing meta box" error

[gabriele-v]

Hello,
I need to extract some additional data (GoPro GPS data) from a MP4 file and add them to another MP4 file.
I'm able to extract them with the command
mp4box.exe -raw 3 ..\video.mp4

But when I try to import them again with this command
mp4box.exe -add ..\GoproVideo.mp4 -set-meta meta:tk=3 -add-item ..\video_track3.gpmd:tk=3 -new output.mp4

I got the following error
Trying to add item, but missing meta box

Am I missing something? Looking at the documentation, command line seems ok because I set the meta type and then add the item to it. Should I create first the track3? Or is automatically created with the set-meta command?

This is what I get if I run a -info on the original file

# Track 3 Info - ID 3 - TimeScale 1000
Media Duration 00:14:41.526
Track has 2 edits: track duration is 00:14:41.628
Track flags: Enabled In Movie In Preview
Media Samples: 8801
1 UDTA types:
        meta:
Media Type: meta:gpmd
        Unknown Metadata Stream
        RFC6381 Codec Parameters: gpmd
        All samples are sync
        Max sample duration: 104 / 1000

Thanks for reporting your issue. Please make sure these boxes are checked before submitting your issue - thank you!

• I looked for a similar issue and couldn't find any.
• I tried with the latest version of GPAC. Installers available at https://gpac.io/downloads/gpac-nightly-builds/
• I give enough information for contributors to reproduce my issue (meaningful title, github labels, platform and compiler, command-line ...). I can share files anonymously with this dropbox: https://www.mediafire.com/filedrop/filedrop_hosted.php?drop=eec9e058a9486fe4e99c33021481d9e1826ca9dbc242a6cfaab0fe95da5e5d95

Detailed guidelines: https://gpac.io/bug-reporting/

[jeanlf]

I looks like trackID 3 is no longer present after import (I added a more explicit check in mp4box for that).

Can you run a -info on the output file without the -set-meta and -add-item options ?

[gabriele-v]

Hi @jeanlf sorry for the dealy.
I confirm that I don't have any trackID 3 in the output file, I was thinking i''s created by -set-meta meta:tk=3
Is there a way to create it and then import back my file as raw track?
I'm looking at gpac.exe filters as well but I'm not able to make it working.

Thanks!

EDIT: If I use for example this command mp4box.exe -add GoproVideo.mp4 -add video.mp4#trackID=3 -new output.mp4 looks like TrackID3 is added, even if not present, but I want to do it from my raw file, not extarcting from another track.
Trying with mp4box.exe -add GoproVideo.mp4 -add video_track3.gpmd -new output.mp4 I have this error:

[FFDmx] Fail to open video_track3.gpmd - error Invalid data found when processing input
Filter ffdmx failed to setup: Filter not found for the desired type
Filters not connected:
mp4mx (importer:file=0000028BE3235890) (idx=1)
[Importer] Error importing video_track3.gpmd