On 2/5/16, Dave Rice <d...@dericed.com> wrote: > Hi all, > I am having trouble creating an mpeg2video output that conforms to 16-235 > broadcast range. I'd like to find a way to have an input which is yuv420p > but has luma values out of broadcast range but clip to broadcast range while > encoding to mpeg2. > > To demonstrate the issue, I generate a yuv420p file with samples in the out > of broadcast range via: > > ffmpeg -f lavfi -i > "nullsrc=s=256x256,geq=random(1)/hypot(X-cos(N*0.07)*W/2-W/2\,Y-sin(N*0.09)*H/2-H/2)^2*1000000*sin(N*0.02):128:128" > -c:v ffv1 -t 10 sample.mkv > > I can then clip the samples using clipval in the lut filter and see the > clipped values in a waveform with: > > ffmpeg -i sample.mkv -vf lut=y=clipval:u=clipval:v=clipval -c:v ffv1 -f nut > - | ffplay - -vf waveform > The waveform shows the values clipped at 16 and 235. > > However I need the output to use mpeg2video. When I change lossless ffv1 to > mpeg2video with: > > ffmpeg -i sample.mkv -vf lut=y=clipval:u=clipval:v=clipval -c:v mpeg2video > -f nut - | ffplay - -vf waveform > > The output shows many sample values above 235. The lossy mpeg2video encoding > seems to place values above 235 while the lossless ffv1 doesn't. Is there a > way to encode in mpeg2video without having values over 235 in the output?
Appears to be mpeg2video bug, can others confirm? _______________________________________________ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-user
