On 9/4/2016 4:06 PM, Carl Eugen Hoyos wrote: > 2016-09-04 16:02 GMT+02:00 Timo Rothenpieler <t...@rothenpieler.org>: >> The purpose of this patch is to make conversion from >> yuv420p (8 bit) to p010 (10 bit) fast. > > Do I understand you correctly that your patch is > faster without the change I suggested?
With the &: [bench @ 0x600045b80] t:0.011178 avg:0.011172 max:0.018297 min:0.010505 Without it: [bench @ 0x600045b80] t:0.008455 avg:0.008517 max:0.015815 min:0.007941 So it is quite a bit faster. Tested with nvenc hevc10 encoding, and the output is visually identical, and the file size is also exactly the same. So it seems to cleanly ignore the unused bits. Also, given that at least microsoft argues with upcasting to 16 bit, the approach without zeroing the lsb would be more accurate, as t << 8 | t is how one would convert 8 bit to 16 bit. So I'd say going with the faster approach here should be fine. If at some point someone runs into something that chokes on the bits being non-zero, which I think is highly unlikely, it can be changed back. _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel