[FFmpeg-devel] [PATCH] libavutil: add clean aperture (CLAP) side data.

[Lynne]

Apr 27, 2020, 05:27 by neil.birkbeck at gmail.com:

> The clean aperature represents a cropping of the stored image data used to
> relate the image data to a canonical video system and exists as container
> metadata (see 'clap' section in https://developer.apple.com/library/archive/documentation/QuickTime/QTFF/QTFFChap3/qtff3.html)
>
> Addition of the side data is a first step towards demuxing CLAP atom metadata,
> helping to resolve https://trac.ffmpeg.org/ticket/7437
>
> This CleanAperture representation can also carry PixelCrop fields from MKV.
> Side data was suggested as a way to carry such PixelCrop fields in:
> https://ffmpeg.org/pipermail/ffmpeg-devel/2016-March/192302.html
>
> Transmuxing the side data can then be added (MOV to/from MKV), and
> auto-application could optionally be enabled like autorotate in ffmpeg_filter.c.
>

We already have frame cropping metadata in the AVFrame structure.