[FFmpeg-devel] [PATCH] mov: Prioritize aspect ratio values found in pasp atom

[Derek Buitenhuis]

On 07/04/2021 19:56, Vittorio Giovara wrote:
> My OS doesn't even let me install Quicktime 7, if anybody could chime in
> and help solve this point it would be much appreciated.
> Alternatively, I'd say we shouldn't cargo cult broken files generated by 11
> year old software, but if people disagree we can leave things as they are.

For MP4, at least, there is a definitive answer from ISO/IEC 

    The pixel aspect ratio and clean aperture of the video may be specified using the ‘pasp’ and ‘clap’
    sample entry boxes, respectively. These are both optional; if present, they over-ride the declarations (if any) in 
    structures specific to the video codec, which structures should be examined if these boxes are absent. For 
    maximum compatibility, these boxes should follow, not precede, any boxes defined in or required by derived 
    specifications. 

- Derek