[mythtv-commits] Ticket #3925: mythcommflag gets mpeg2video errors not seen in playback

[MythTV]

#3925: mythcommflag gets mpeg2video errors not seen in playback
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 Reporter:  anonymous  |        Owner:  ijr    
     Type:  defect     |       Status:  new    
 Priority:  major      |    Milestone:  unknown
Component:  mythtv     |      Version:  unknown
 Severity:  medium     |   Resolution:         
  Mlocked:  0          |  
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Comment(by km at mathcs.emory.edu):

 My initial thought about wrong codec was wrong. The same mpeg2 decode is
 done in all cases.

 The problem boils down to this. The errors don't show when playing the
 streams because they are played sequentially. mythcommflag seeks forward
 skipping frames incorrectly for these streams and then tries to decode
 garbage. Eventually it recovers but the indexing is off.

 I need someone more expert than me to help look at a sample stream and
 help pin down the error. I have a 1MB stream that illustrates the problem.
 mythcommflag tries to skip from frame 30 to frame 58 and thats where the
 problem occurs. mpeg_decode_frame is called 5 times successfully, the 6th
 time follows a AvFormatDecoder::SeekReset which attempts to skip 28
 frames, and this one is given garbage.

 1MB exceeds the largest file I can attach, so please contact me if you
 would like to have a look.

 This is not an isolated problem.

-- 
Ticket URL: <http://svn.mythtv.org/trac/ticket/3925#comment:1>
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