W dniu 2017-10-20 o 20:07, Jan Ekstrom pisze: > On Fri, Oct 20, 2017 at 10:26 AM, Mateusz <mateu...@poczta.onet.pl> wrote: >> W dniu 2017-10-06 o 17:33, Mateusz pisze: >>> Fixed DITHER_COPY macro (only C code), updated FATE tests. >>> >>> PSNR in tests that needed update goes from 50 to 999.99 -- the quality is >>> there. >> >> Ping. > > Hi, > > The updated PSNR values look really good (and the max difference going > from 1 to 0), but unfortunately I lack the capacity to verify that the > code is doing the same thing as the original thing. > > Can we please have someone's eyes on this? If a patchwork URL makes it > simpler, it's https://patchwork.ffmpeg.org/patch/5440/ . > > > Jan
There was discussion about this code in thread "swscale_unscaled: fix DITHER_COPY macro, use it only for dst_depth == 8". Conclusion was that it should be the same code for dst_depth from 8 to 15 bit (in all possible cases). The worse quality scenario for this DITHER_COPY macro is when dst_depth is 8. It is hard to see differences from normal 8 bit to dithered 8 bit (too good quality). I've prepared example movies with new DITHER_COPY macro versus downshift only with dst_depth == 5 (impossible in normal code, only for testing). Movie Sintel in resolution 2K with bit depth 5 (original 5 most significant bits): www.msystem.waw.pl/x265/sintel-org5.mkv The same movie with bit depth 5, but dithered 5 bit instead of original: www.msystem.waw.pl/x265/sintel-dit5.mkv Mateusz _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
