[FFmpeg-trac] #3448(undetermined:new): problem when seeking with an mp4 file

[FFmpeg]

#3448: problem when seeking with an mp4 file
-------------------------------------+-------------------------------------
             Reporter:  galkahana    |                     Type:  defect
               Status:  new          |                 Priority:  normal
            Component:               |                  Version:
  undetermined                       |  unspecified
             Keywords:  seek,mp4     |               Blocked By:
             Blocking:               |  Reproduced by developer:  0
Analyzed by developer:  0            |
-------------------------------------+-------------------------------------
 Summary of the bug:
 i am trying to created a version of seg_2_1_1.mp4 without the first half a
 second.
 i am running the command "ffmpeg -y -i seg_2_1_1.mp4 -ss 0.5 -c copy
 seg_2_1_1_cut.mp4" to do this.
 problem is the result is wrong. Seems like too much video is cut.
 Checking with ffprobe i see that the output streams are desynched - the
 video stream is
 shorter than the audio stream in about half a second, and is offset by 0.6
 seconds.
 i would like NOT to lose that extra half a second.

 for some reason, when encoding, even just the video stream, doing
 something like this:
 "ffmpeg -y -i seg_2_1_1.mp4 -ss 0.5 -c:a copy seg_2_1_1_cut.mp4"
 The problem is solved. however, this takes more time, so i'd like to
 avoid.

 How to reproduce:
 {{{
 % ffmpeg -y -i seg_2_1_1.mp4 -ss 0.5 -c copy seg_2_1_1_cut.mp4
 ffmpeg version N-61105-gbba7b6f
 built on  Mar  5 2014 22:01:31 with gcc 4.8.2
 }}}

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Ticket URL: <https://trac.ffmpeg.org/ticket/3448>
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