Hi,

I tried to extract the box info of a segment using MP4Box with `-diso` option. I got `[iso file] Unknown top-level box type imda
` and `Error opening file <file_name>.mp4: IsoMedia File is truncated`.

Windows 64 bits
```
> MP4Box -version 
MP4Box - GPAC version 2.1-DEV-rev426-g3b6f2436-master
```

the sample video: https://www.mediafire.com/file/ungdop0ywxrenvk/omafv2.0.base.1.mp4/file


Unknown top-level box type imda
This is a GitHub Issue
repo:gpac
owner:gpac
Title : Unknown top-level box type imda
Issue date:

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Hi,

I tried to extract the box info of a segment using MP4Box with `-diso` option. I got `[iso file] Unknown top-level box type imda
` and `Error opening file <file_name>.mp4: IsoMedia File is truncated`.

Windows 64 bits
```
> MP4Box -version 
MP4Box - GPAC version 2.1-DEV-rev426-g3b6f2436-master
```

the sample video: https://www.mediafire.com/file/ungdop0ywxrenvk/omafv2.0.base.1.mp4/file


--- end body ---
