On 1 Jul 2017, at 20:24, Sasi Inguva <[email protected]> wrote: >> On Sat, Jul 1, 2017 at 6:56 AM, Mark Burton [via FFmpeg-users] >> How about this for a partial solution - ffmpeg supports the audiotoolbox >> aac encoder on macOS. For the sake of being able to create .mov which are >> compatible with the Quicktime format, there is a single change which I >> think could work well, albeit the ‘fix' would be limited to macOS system >> encoders. >> >> Currently a .mov created by ffmpeg when using the aac_at audiotoolbox >> encoder creates a sound track edit list with a media time of 2112. This >> will not work with Quicktime decoders, the file with decode out of sync. If >> this value was 0 however, then the file will decode properly in sync. >> >> For now, would it be possible to change this value to 0 when using the >> aac_at encoder in ffmpeg? >> >> Doing the same for the ffmpeg native aac encoder does help quite a bit, >> about 1/2 frame out of sync as opposed to a full frame.
> > There is already a flag called -use_editlist in ffmpeg MOV muxer > http://git.videolan.org/?p=ffmpeg.git;a=blob;f=libavformat/movenc.c;h=ca389e3a97f92e05b1abfda29aa7bde25e1089a0;hb=HEAD#l88 > > <http://git.videolan.org/?p=ffmpeg.git;a=blob;f=libavformat/movenc.c;h=ca389e3a97f92e05b1abfda29aa7bde25e1089a0;hb=HEAD#l88> > I think you can use that along with the audiotoolbox encoder to achieve what > you want. I have tried this before, but by removing the editlist using this flag, the resulting file had major frame rate issues - for example a 24fps file, would come out at 23.99fps and would not play correctly - using my test file with burnt in timecode and a timecode track, it was easy to see that they were not keeping sync. This also results in a file which is longer than the true duration and Quicktime decoders can display a black frame at the end as a result. Perhaps this is because the edit list is removed from all tracks, not just the audio, I don’t know, but it doesn’t currently achieve what I described above sadly. _______________________________________________ ffmpeg-user mailing list [email protected] http://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email [email protected] with subject "unsubscribe".
