Nikolay Sivov (@nsivov) commented about dlls/mfreadwrite/reader.c:
-static HRESULT source_reader_create_transform(struct source_reader *reader, +static BOOL source_reader_allow_video_processor(struct source_reader *reader, BOOL *advanced) +{ + UINT32 value; + + *advanced = FALSE; + if (!reader->attributes) + return FALSE; + + if (SUCCEEDED(IMFAttributes_GetUINT32(reader->attributes, &MF_SOURCE_READER_ENABLE_ADVANCED_VIDEO_PROCESSING, &value))) + *advanced = value; + if (SUCCEEDED(IMFAttributes_GetUINT32(reader->attributes, &MF_SOURCE_READER_ENABLE_VIDEO_PROCESSING, &value))) + return value || *advanced; + + return *advanced; +} I think on Windows it's to distinguish between "simpler" color conversion and VideoProcessorMFT. I don't know if we care too much, but it's obviously exposed to applications.
-- https://gitlab.winehq.org/wine/wine/-/merge_requests/5120#note_62812