[FFmpeg-devel] [PATCH] avformat/matroskaenc: always reserve max aac private data

[John Stebbins]

On Fri, 2020-05-01 at 19:53 +0200, Nicolas George wrote:
> John Stebbins (12020-05-01):
> > The test case is a TS file with aac audio.  It TS files, it is
> > certainly possible for stream parameters to change on the fly. But,
> > if
> > the extradata changes, there's really no way to handle it in mkv
> > since
> > this data is global in mkv.  So perhaps a better solution is to
> > ignore
> > side data extradata if it's already been written once?
> 
> Would it not lead to a corrupted file, possibly unplayable?
> 
> 

If the parameters change on the fly, some part of the audio stream is
going to be unplayable.  Either the part after the change will be
unplayable if you ignore extradata changes, or everything preceeding 
the last extradata change will be unplayable if you rewrite codec
private on every change.