[FFmpeg-devel] [PATCH][RFC - DO NOT MERGE] Revert "mov: Discard invalid CTTS."

[Derek Buitenhuis]

On 08/03/2021 17:29, Michael Niedermayer wrote:
> I would try to detect the specific abberant muxer based on the input. 
> Then have custom code in the demuxer which is based on reverse engnenering the 
> issue to do a best effort to recover as much as is possible. And also print a big 
> warning about the broken input / muxer so the user doesnt stay unaware.

I mean, I already listed the options in my email. Best you can do is try and check
for insane PTS/DTS diff (I proposed 16 frames), and the 'fix' of dropping the CTTS
info just makes it broken in a different way.

> You can see this also in 2 ways
> 1. It sucks its not our job to workaround someone elses bugs
> 2. It cool, it gives FFmpegs demuxer a unique advantage over competing demuxers

As an API user, I do not see returning made up PTS/DTS rather than what is in file
as an advantage. At least if I have what is in the file, I can make my own decisions
in my program, on how to handle it.

As it stands right now, as detailed in my previous mail, I have no way to even detect
these files since avformat handles them differently depending on if the file hits
the arbitary number of 1<<28.

What I'm looking for here is something actionable: I know what the possibilities are
for changes/fixes. Which the community prefers are not clear. As it stands, it is
just broken.

- Derek