[FFmpeg-trac] #4769(ffmpeg:new): Concatenate: Audio and Video out of sync after a couple of rounds

FFmpeg trac at avcodec.org
Tue Aug 11 20:08:43 CEST 2015


#4769: Concatenate: Audio and Video out of sync after a couple of rounds
-------------------------------------+-------------------------------------
             Reporter:  Timster      |                     Type:  defect
               Status:  new          |                 Priority:  normal
            Component:  ffmpeg       |                  Version:  git-
             Keywords:  ffmpeg,      |  master
  concatenate, desync, audio, video  |               Blocked By:
             Blocking:               |  Reproduced by developer:  0
Analyzed by developer:  0            |
-------------------------------------+-------------------------------------
 Hello!

 Summary of the bug:

 There is an issue with concatenating video files. After several rounds of
 concatenation, the audio and video desync. The issue also occurs when just
 concatenating one video file with itself several times so it can't be due
 to video/audio settings being incompatible with each other. Different
 containers/settings as well don't change anything.

 This is the command I am using:

 ffmpeg -f concat -i <(for i in `seq 5`; do printf "file %s\n"
 /path/to/*.mkv; done) -c:v h264 -preset slow -b:v 1500k -minrate 1500k
 -maxrate 1500k -bufsize 1500k -g 80 -c:a copy out1.mkv


 It is a regression - I've have tested it with the static build
 ffmpeg.static.64bit.2014-07-16 - it is working there. With my ppa build or
 the git build it doesn't. The output is attached - produced with the ppa
 build.


 Best,
 Tim

--
Ticket URL: <https://trac.ffmpeg.org/ticket/4769>
FFmpeg <https://ffmpeg.org>
FFmpeg issue tracker


More information about the FFmpeg-trac mailing list