[mythtv-commits] Ticket #12010: mythcommflag --rebuild does not re-create good seektables with h264 recordings

[MythTV]

#12010: mythcommflag --rebuild does not re-create good seektables with h264
recordings
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     Reporter:  J.Pilk@…             |      Owner:
         Type:  Bug Report -         |     Status:  new
  General                            |  Milestone:  unknown
     Priority:  minor                |    Version:  0.27-fixes
    Component:  MythTV - General     |   Keywords:  mythcommflag --rebuild
     Severity:  medium               |  h264
Ticket locked:  0                    |
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 This looks like a re-run of #11435 and #6243.  Initial report here, quoted
 below.

 http://www.gossamer-threads.com/lists/mythtv/users/561003#561003

 I have just found that for recordings from DVB-T2 FreeviewHD in the UK,
 (h264), a listing of the markup data generated after mythcommflag
 --rebuild contains only a small subset of the lines in a similar listing
 made immediately after recording.

 In the 'original' table, keyframe separation is typically around 24
 frames. In the 'rebuilt' table the spacing is variable, sometimes in the
 hundreds of frames. Points listed there are also in the original table.

 hexdump shows that all keyframes in the original list for this recording
 begin 47 40 65 3x, and to me look genuine.  The problem does not affect
 DVB-T SD recordings, which are mpeg2 format.

 In my tests I have usually been working with recordings having seektables
 that have been rebuilt, often several times. This may explain why editing
 has sometimes been difficult.

 mythutil --chanid 1102 --starttime 20140109182600 --getmarkup
 Haworth_orig.xml
 mythcommflag --rebuild --chanid 1102 --starttime 20140109182600
 mythutil --chanid 1102 --starttime 20140109182600 --getmarkup
 Haworth_rebuilt.xml

 ls -l Haw*
 -rw-rw-r--. 1 john john 290708 Jan 9 19:13 Haworth_orig.xml
 -rw-rw-r--. 1 john john 73286 Jan 9 19:16 Haworth_rebuilt.xml

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Ticket URL: <http://code.mythtv.org/trac/ticket/12010>
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