On Sun, Apr 17, 2016 at 09:49:58PM +0300, Jan Ekstrom wrote: > On Sun, Apr 17, 2016 at 9:44 PM, wm4 <nfx...@googlemail.com> wrote: > > > > Ah that's funny. This indeed ruins everything. It looks like subtitle > > decoders should simply output YUV, and until we can fix it, a private > > option could change between the colorspaces? > > Well, the colorimetry is at least specified as per the resolution, and > while I haven't confirmed it I would guess you could decide things by > the size of the "canvas", since it seems like SD content has been > deemed Rec.601, while HD content has been deemed Rec.709). > > Of course, I do agree that enabling YCbCr output could be one way of > getting through this for some users of the API.
One suspicion: Does the spec say anything on alpha blending? Because this close relation with video colour space sounds a lot like alpha-blending might have been intended to be done in YUV space. Which would potentially give quite different results from doing it in RGB. _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
