It was noticed that -copy hwdec modes typically dropped the
chroma_location field. This happened because the attributes on hw
download are copied with mp_image_copy_attributes(), which tries to copy
these parameters only if src and dst were both YUV (in an attempt to
copy parameters only if it makes sense).
But hardware formats did not have the YUV flag set (anymore?), and code
shouldn't attempt to check the flag in this way anyway. Drop the check,
and always copy the whole color metadata struct. There is a call to
mp_image_params_guess_csp() below, which tries to unset nonsense
metadata if it was copied from a YUV format to RGB. This function would
also do the right thing for hw formats (although for the cited bug only
the software case matters).
Fixes#4804.
810990a746