Hello,

I'm playing around with some sample files I found in Google's `CtsMediaTestCases`, but some of them seem to be unrecognized by GPAC.

I've uploaded the mp4 here: https://www.mediafire.com/file/wsyt42zw7mf5fxs/video_dovi_3840x2160_30fps_dav1_10.mp4/file
And a demuxed OBU file here: https://www.mediafire.com/file/ee16i6lsoaeug09/dav1_10.obu/file
(According to the template, that's how it should be done..)

The demuxed video was obtained with Dolby's tool: https://github.com/DolbyLaboratories/dlb_mp4demux

When probing with `gpac` I get this:
```
gpac probe -i video_dovi_3840x2160_30fps_dav1_10.mp4
[iso file] Read Box "sgpd" (start 1460337) failed (Invalid IsoMedia File) - skipping
[iso file] Read Box "stbl" (start 1458670) failed (Invalid IsoMedia File) - skipping
[iso file] Read Box "minf" (start 1458606) failed (Invalid IsoMedia File) - skipping
[iso file] Read Box "mdia" (start 1458521) failed (Invalid IsoMedia File) - skipping
[iso file] Read Box "trak" (start 1458385) failed (Invalid IsoMedia File) - skipping
[iso file] Read Box "moov" (start 1458269) failed (Invalid IsoMedia File) - skipping
[IsoMedia] error while opening video_dovi_3840x2160_30fps_dav1_10.mp4, error=Invalid IsoMedia File
Failed to connect filter fin PID video_dovi_3840x2160_30fps_dav1_10.mp4 to filter mp4dmx: Invalid IsoMedia File
Blacklisting mp4dmx as output from fin and retrying connections
session last connect error Filter not found for the desired type
```

And when trying to remux:
```
MP4Box -add dav1_10.obu -new test.mp4
[AV1] parsing for metadata is not implemented. Forwarding.
[Importer] Error probing dav1_10.obu
Error importing dav1_10.obu: Bad Buffer size (too small)
```

Now I think this might be an experimental file, but I'm not sure at all.
The OBU file parses correctly using https://github.com/yohhoy/av1parser
But `aomdec` does say the frames are corrupted.

The file also does not seem to follow AV1's ITU-T T.35 specification for the Dolby Vision metadata, so it might just be bogus.

I am using GPAC on Arch Linux, 64 bits.
`gpac - GPAC command line filter engine - version 1.0.1-rev0-gd8538e8ae-makepkg`
Errors when probing/muxing dav1 video file
This is a GitHub Issue
repo:gpac
owner:gpac
Title : Errors when probing/muxing dav1 video file
Issue date:

--- start body ---
Hello,

I'm playing around with some sample files I found in Google's `CtsMediaTestCases`, but some of them seem to be unrecognized by GPAC.

I've uploaded the mp4 here: https://www.mediafire.com/file/wsyt42zw7mf5fxs/video_dovi_3840x2160_30fps_dav1_10.mp4/file
And a demuxed OBU file here: https://www.mediafire.com/file/ee16i6lsoaeug09/dav1_10.obu/file
(According to the template, that's how it should be done..)

The demuxed video was obtained with Dolby's tool: https://github.com/DolbyLaboratories/dlb_mp4demux

When probing with `gpac` I get this:
```
gpac probe -i video_dovi_3840x2160_30fps_dav1_10.mp4
[iso file] Read Box "sgpd" (start 1460337) failed (Invalid IsoMedia File) - skipping
[iso file] Read Box "stbl" (start 1458670) failed (Invalid IsoMedia File) - skipping
[iso file] Read Box "minf" (start 1458606) failed (Invalid IsoMedia File) - skipping
[iso file] Read Box "mdia" (start 1458521) failed (Invalid IsoMedia File) - skipping
[iso file] Read Box "trak" (start 1458385) failed (Invalid IsoMedia File) - skipping
[iso file] Read Box "moov" (start 1458269) failed (Invalid IsoMedia File) - skipping
[IsoMedia] error while opening video_dovi_3840x2160_30fps_dav1_10.mp4, error=Invalid IsoMedia File
Failed to connect filter fin PID video_dovi_3840x2160_30fps_dav1_10.mp4 to filter mp4dmx: Invalid IsoMedia File
Blacklisting mp4dmx as output from fin and retrying connections
session last connect error Filter not found for the desired type
```

And when trying to remux:
```
MP4Box -add dav1_10.obu -new test.mp4
[AV1] parsing for metadata is not implemented. Forwarding.
[Importer] Error probing dav1_10.obu
Error importing dav1_10.obu: Bad Buffer size (too small)
```

Now I think this might be an experimental file, but I'm not sure at all.
The OBU file parses correctly using https://github.com/yohhoy/av1parser
But `aomdec` does say the frames are corrupted.

The file also does not seem to follow AV1's ITU-T T.35 specification for the Dolby Vision metadata, so it might just be bogus.

I am using GPAC on Arch Linux, 64 bits.
`gpac - GPAC command line filter engine - version 1.0.1-rev0-gd8538e8ae-makepkg`
--- end body ---
