On Fri, 5 Aug 2016 17:18:39 -0700 Sasi Inguva <isasi-at-google....@ffmpeg.org> wrote:
> In YouTube we have long been receiving MOV files from users, which have > non-trivial edit lists (Those edit lists which are not just used to offset > video start from audio start) and multiple edit lists. Recently the uploads > of such files has increased with the introduction of apps that allow video > editing and upload like Vine etc. mov.c in ffmpeg does not have edit list > parsing support i.e. the support for deciding what video/audio packets should > be output with what timestamps, based on edit lists. For this reason, we had > built a basic support for edit list parsing in our version of ffmpeg, which > fixes the AVIndexEntries built by mov_build_index by looking at edit lists, > and introduces new DISCARD flags in AVPacket and AVFrame to signal to the > decoder to discard certain packets. > > For a while our edit list support was broken, as in it didn't properly work > for multiple edit lists and it had problems with edit-lists ending on > B-frames. But we've fixed most of these issues in recent times, and we think > that now it is in a good enough condition so that it can be submitted to > HEAD. This will not only help the vast userbase of ffmepg, but will also help > us with staying up-to-date with ffmpeg and also by adding the power of ffmpeg > developer community to our MOV support. So here's a go at it. > What is supported: > - multiple edit lists > - edit lists ending on B-frames > - zero segment duration edit lists > > What is not supported: > - Changing the rate of playing with edit lists. We basically ignore > MediaRate field of edit. > > I have added fate tests too. Here is a no-sign-in required link to the test > files > https://drive.google.com/folderview?id=0Bz6XfEJZ-9N3R3o3QXNHUGRqbms&usp=sharing. This still makes demuxers output packets with _not_ strictly monotonically increasing DTS timestamps. Please fix this - a demuxer isn't supposed to do this, and it's completely broken. _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
