Hi Christoph, > On May 20, 2015, at 1:59 AM, Christoph Gerstbauer > <christophgerstba...@gmail.com> wrote: > > Am 19.05.15 um 23:06 schrieb Carl Eugen Hoyos: >> Christoph Gerstbauer <christoph.gerstbauer <at> gmail.com> writes: >> >>> C:\Windows\System32>ffmpeg -i >>> C:\Users\Administrator\Desktop\big_buck_bunny_ffvhuff.avi -vf >>> "scale=in_range=full:out_range=tv" -vcodec ffvhuff >> It seems to me that the scale filter is so smart >> that it doesn't scale if the input and output >> resolution and input and output colourspace >> are identical. >> >> Even worse, both the filter and the software >> scaler are smart enough to skip actual scaling, >> so fixing the issue in the scale filter is not >> sufficient... >> >> I am not 100% sure if this is a bug, but it >> seems so;-) >> >> (Please try to understand that I had no idea >> what you are talking about until seeing your >> - imo sensible - command line.) >> >> I hope you mean "to correct 0-255 to 16-235". >> > YES. thats what I want to do: correction to 16-235 levels. > I am checking different files with QCtools. It shows me optical if the values > are above 235 or under 16. A numerical way would be much better, of course. > But that is another issue.
QCTools quantifies samples out of the 16-235 range with the BRNG value from the signalstats filter. You can get the same numbers (range of 0-1) via: ffprobe -f lavfi movie=input.mov,signalstats=stat=brng -show_entries frame_tags=lavfi.signalstats.BRNG -of flat Dave Rice _______________________________________________ ffmpeg-user mailing list ffmpeg-user@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-user