[FFmpeg-devel] [PATCH v1 1/2] lavc/vp9: set yuvj pixel format for full range decode

[Thilo Borgmann]

Am 17.06.23 um 16:02 schrieb Leo Izen:
> On 6/17/23 04:11, Thilo Borgmann wrote:
>> While the yuvj pixel formats are deprecated lots of code still relies
>> on them to be set. Without setting a yuvj420p pixel format VP9
>> decoding ends up incorrectly due to auto conversion.
>>
> 
> I oppose this on principle. If there's code that relies on YUVJ being set, then *that code* needs to be changed so it respects the AVFrame->color_range field. Which code is working improperly with this?

I don't like adding YUVJ stuff either. If I do

  ./ffmpeg -i full-range-in.mp4 -c:v libvpx-vp9 -lossless 1 lossless-out.mp4

and then comparing the frames, they are not equal. E.g. by

  ./ffmpeg -i full-range-in.mp4 -i lossless-out.mp4 -filter_complex ssim -f crc -

they are not 1.0 in ssim terms.


I agree, maybe the same effect can be fixed somewhere else and if so it could effect more codecs than VP9. You (or anyone) have an idea?

Thanks,
Thilo