The veai filter is running in RGB color space, and codecs such as ProRes are in YUV color space, so the conversion process occurs.
FFMPEG will cause an overall whitish color alteration when converting from RGB color space to YUV color space if the right options are not set.
https://trac.ffmpeg.org/wiki/colorspace
Try adding the following FFMPEG options on the command line.
Written before filters
-sws_flags spline+accurate_rnd+full_chroma_int
Written the end of the filter
,colorspace=bt709:iall=bt601-6-525:fast=1
Example
input.mp4(bt709) → output.mov(Proteus ProRes422 bt709,yuv422p10le)
ffmpeg -y -i input.mp4 -vf veai_up=device=-2:model=prob-3:scale=2:compression=0.24:details=0.24:blur=0:noise=0.12:halo=0:preblur=0 -color_primaries 1 -color_trc 1 -colorspace 1 -an -c:v prores_ks -profile:v 3 -vendor apl0 -pix_fmt yuv422p10le output.mov
ffmpeg -y -i input.mp4 -sws_flags spline+accurate_rnd+full_chroma_int -vf veai_up=device=-2:model=prob-3:scale=2:compression=0.24:details=0.24:blur=0:noise=0.12:halo=0:preblur=0,colorspace=bt709:iall=bt601-6-625:fast=1 -color_primaries 1 -color_trc 1 -colorspace 1 -an -c:v prores_ks -profile:v 3 -vendor apl0 -pix_fmt yuv422p10le output.mov
