вт, 8 июн. 2021 г., 5:28 Michael Bradshaw <mjbshaw-at-google....@ffmpeg.org >:
> I'll just chime in and say: > > FIXME comments aren't that helpful. It would be more helpful to av_log when > you detect you've hit an unsupported situation. > How should I know what are unsupported situations? I mean sure, sYCC (BT.709 primaries with BT.601 matrix and sRGB transfer) is such a case, but I am not sure what else and it is impossible to detect it (also BT.601 matrix with classic BT.601/709/2020 transfer and SMPTE C primaries, like on trac)). Because were it possible, I would have JUST FIXED IT. Also, that will still be not enough as primaries must be also color managed, except ffplay does not support color managment. BT.601 matrix vs BT.709 matrix vs BT.2020-ncl matrix is not all, I hope you understand that. With the case BT.2020-ncl it is not it that make it that bad for BT.2100 (HDR). It is PQ transfer function. Not even primaries. As for SMPTE 240M vs BT.601 Y'CbCr matrices: yes, they're different. But > SDL doesn't support SMPTE 240M. It only supports: > Yes, I know that. Can you imagine?? Oh, my. > SDL_YUV_CONVERSION_JPEG, /**< Full range JPEG */ > SDL_YUV_CONVERSION_BT601, /**< BT.601 (the default) */ > SDL_YUV_CONVERSION_BT709, /**< BT.709 */ > (and automatic, but that's just BT.601 + BT.709) > > It's probably better to fall back to using BT.709 matrix for SMPTE 240M > (with a warning log) since BT.709 is closer to SMPTE 240M than BT.601 is. > No. This uses sRGB transfer. sRGB transfer is not close BT.709 OETF (or its BT.1886 EOTF) because sRGB is an EOTF in by itself. Please do not say it again. _______________________________________________ > ffmpeg-devel mailing list > ffmpeg-devel@ffmpeg.org > https://ffmpeg.org/mailman/listinfo/ffmpeg-devel > > To unsubscribe, visit link above, or email > ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe". > _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
