Fix T94237: Glitch when copying unaligned ffmpeg buffer

Using a negative linesize to flip an image vertically is supported in
ffmpeg but not for every function.

This method treats frames that need and those that do not need alignment
the same. An RGBA frame buffer with alignment that ffmpeg decides is
optimal for the CPU and build options is allocated by ffmpeg.
The `sws_scale` does the colorspace transformation into this RGBA frame
buffer without flipping. Now the image is upside down and aligned.
The combined unaligning and vertical flipping is then done by
`av_image_copy_to_buffer` which seems to handle negative linesize
correctly.

Reviewed By: ISS

Differential Revision: https://developer.blender.org/D13908

0 files changed, 0 insertions, 0 deletions