Part of overall #118493 task: video input/output support at 10 and 12
bit/component formats. (note: this is still LDR videos just at higher
precision; there's no HDR handling (yet)).
Movie reading/playback: when movie file pixel format has >8 bit
components, decode those into a floating point ImBuf result. Previously
all movies were decoded into 8 bit/channel ImBufs, so 10- and 12-bit
movie pixel colors were getting quantized.
Movie output: when ffmpeg video with suitable codec is selected,
there's a color depth setting under Encoding block. Currently that is:
- 10 bit option for H.264, H.265, AV1 (VP9 could do 10 bit in theory too,
but ffmpeg that is built in Blender does not have that compiled in)
- 12 bit option for H.265, AV1
When "lossless" is picked, then similar to how for regular 8-bit video
it switches from YUV 4:2:0 to 4:4:4, this also switches to 4:4:4
10- or 12-bit variant.
Pull Request: https://projects.blender.org/blender/blender/pulls/129298