Good explanation, I neglected telecine; wasn't aware of how it worked. Agreed, yadif should handle that, the decoder cannot reverse-telecine by itself without some kind of hinting of the original frames correspondence. Thanks a lot.
2015-01-05 18:35 GMT-05:00 Michael Niedermayer <michae...@gmx.at>: > On Mon, Jan 05, 2015 at 03:17:32PM -0500, Vanista Herion wrote: > > Some MPEG 2 video will give bad interlacing information in AVFrame. If > the > > parameters are used by a deinterlace filter such as yadif, frames will be > > processed needlessly and impair the quality. > > > > By reviewing the code in mpegvideo.c which sets the interlaced_frame > > and top_field_first, I noticed that picture_structure is not considered > > whereas it probably supersedes everything else. The H.262 specification > is > > not very clear on that but in the case of this sample, the stream is > > definitely progressive, picture_structure is equal to 3 (Frame picture) > and > > top_field_first alternates true and false. > > > > The result is that frames come out reported as tff, bff and progressive, > > cycling at every frame. > > I propose a simple patch to set interlaced_frame to false when > > picture_structure is equal to PICT_FRAME. > > fixed differently, that is by detecting telecined content in yadif > > [...] > > -- > Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB > > When the tyrant has disposed of foreign enemies by conquest or treaty, and > there is nothing more to fear from them, then he is always stirring up > some war or other, in order that the people may require a leader. -- Plato > _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
