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

[Vittorio Giovara]

On Tue, Apr 6, 2021 at 6:51 PM Vittorio Giovara <vittorio.giovara at gmail.com>
wrote:

> Here is the proposed patch to address samples like trac/7277.
>
> This effectively reverts an 11 year old patch
> (9044dd83991491309ecb76c389502e410897d7d2) but I wasn't able to identify
> the file mentioned in the log.
>
> If anyone knows where to look up the sample in issue 1539 that is not on
> trac I can see if this patch affects it in one way or another, however a
> lot has changed in the mov demuxer so maybe it's not strictly necessary.
>

Carl kindly pointed me to the sample, and I can confirm my patch does
affect how the video looks: without my patch the sample is shown at a 16:9
AR (which I assume was the original fix), with my patch the sample uses an
AR of 1:1 and it is therefore square. However I tried with a recent
Quicktime, and it displays the sample using the square aspect ratio.

What is the preferred course of action? I see three options
 - leave the code as is, no action
 - apply my patch, fixing 7277, but breaking 1539, assuming QT is doing the
right thing
 - add a demuxer option that optionally disables pasp parsing (is it even
worth it?)

Let me know your thoughts
-- 
Vittorio