On Tue, Feb 07, 2017 at 09:07:02PM -0700, Daniel Verkamp wrote: > There is already a rgb24-to-rgb565 path, but it does not get used by > default because of the needsDither check in ff_get_unscaled_swscale(). > If the scaling algorithm is set to fast_bilinear, needsDither is > ignored and the RGB24 to RGB16 converter is used. (In either case, no > actual scaling is performed, so the scaling algorithm is irrelevant > aside from selecting dithering.) Looking at the mplayer docs, this is > probably equivalent to '-sws 0'. > > e.g. > ffmpeg -i <sample> -f null -c rawvideo -pix_fmt rgb565le -sws_flags > fast_bilinear /dev/null > > Using matrixbench_mpeg2.mpg (720x567) encoded with ffmpeg into Cinepak > using default settings, decoding on an i5 3570K, 3.4 GHz: > > bicubic (default): ~24x realtime > fast_bilinear: ~65x realtime > patch w/rgb565 override: ~154x realtime > > As far as I can tell, this patch doesn't do any dithering for RGB565, > so the fast_bilinear (non-dithering) swscale converter is a fair > comparison.
Thanks Daniel. Yes, the patch does accurate rounding, no dithering. Rune _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
