Looks like ffmpeg AVFrame width/height/format for the deinterlaced frame
was never initialized. That was not a problem until starting with 4.1
the colorspace conversion and upside down flip was started to be
multi-threaded, which accessed the frame width/height.
Also, the memory storage for the deinterlaced frame was never freed
either; fix that too.
Pull Request: https://projects.blender.org/blender/blender/pulls/127689
bab4f7a0cd