On 15 Apr 2017, 09:22 +0100, Christian Ebert <[email protected]>, wrote:
> * Mark Burton on Friday, April 14, 2017 at 22:44:52 +0100 > > > On 14 Apr 2017, at 22:22, Christian Ebert <[email protected]> wrote: > > > > > Also, when you run with -v verbose, you'll see a delay (depends > > > > > on audio codec), for you case it's probably 1024. Maybe try: > > > > > > > > > > -filter:a aresample=first_pts=0,asetpts=PTS-STARTPTS+1024 > > > > > > > > 1024 looks correct. This method successfully changes the start, and the > > > > encoded audio plays, almost, 100% in sync. Its slightly cut off at the > > > > head, but only very slightly. However the downside of this method is > > > > that the audio now overruns the end of the picture further and is not > > > > trimmed from remaining samples I’m guessing. This results in a blank > > > > video frame being added to the tail of clip. ffprobe for ffmpeg_v3 > > > > attached. > > > > > > > > I tried using -shortest, but that didn’t help address the above issue. > > > > > > Inserting > > > > > > -t `ffprobe -v quiet -of default=nw=1:nk=1 -select_streams V > > > -show_entries stream=duration SyncTest24p.mov` > > > > > > into your commandline should do the trick. > > > > Adding '-t 2.000000’ to the command does help a little, but ultimately the > > final audio packet is still too large - 6ms in this case - and the black > > frame still occurs. > > Works for me with all my sample results I checked. > > Somewhat counterintuitive, but you never know: > > -filter:a aresample=async=1:first_pts=0,asetpts=PTS-STARTPTS+1024 > > combined with the -t incantation. Same result for me as before - the last packet is too large (1056) and is not being trimmed, so a black frame occurs at the end on playback. When you say it works for you, was that with a Quicktime based decoder? Thanks Mark _______________________________________________ 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".
