[FFmpeg-devel] [PATCH] movenc: write clap tag

Dave Rice dave at dericed.com
Mon Jul 10 02:26:03 EEST 2017

> On Jul 7, 2017, at 7:06 PM, Derek Buitenhuis <derek.buitenhuis at gmail.com> wrote:
> On 7/7/2017 10:13 PM, James Almer wrote:
>> Isn't this necessary only for files with raw video? As is, this box
>> would be written on any mov file with a video stream.
> This was addressed a previous email:
>    http://lists.ffmpeg.org/pipermail/ffmpeg-devel/2017-July/213350.html
> I guess the spec is up for interpretation.

The quicktime spec says "This is a mandatory extension for all uncompressed Y´CbCr data formats”. It doesn’t clarify if the clap atom is recommended or not in mov files that are not “uncompressed Y´CbCr”, though it would make sense if the video container needs to store cropping data. I think constraining the change for only  “uncompressed Y´CbCr” would be more cautious though. I’ll revise my patch to include the condition and resubmit.

If the patch only impacts “uncompressed Y´CbCr” would any fate updates be needed?
Dave Rice

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