[mythtv-commits] Ticket #8875: av-sync lost

[MythTV]

#8875: av-sync lost
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 Reporter:  Markus Schulz <msc@…>              |           Owner:  tralph    
     Type:  defect                             |          Status:  closed    
 Priority:  minor                              |       Milestone:  0.24      
Component:  MythTV - Video Playback            |         Version:  Trunk Head
 Severity:  medium                             |      Resolution:  fixed     
 Keywords:                                     |   Ticket locked:  0         
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Comment (by Markus Schulz <msc@…>):

 Ok, i think i know the problem, i've debugged the time_base values (and
 changed the code to prefer the container fps instead of stream-fps):
 {{{
 2010-10-03 14:49:18.158 AFD: Selected FPS is 25 (matroska 0 stream 25
 container 25 estimated 25 tick_per_frame 1 time base_ 1 / 25)
 2010-10-03 14:49:26.635 AFD: Selected FPS is 23.9761 (matroska 0 stream
 23.9791 container 23.9761 estimated 23.9761 tick_per_frame 1 time base_
 2733 / 65535)
 2010-10-03 14:49:34.762 AFD: Selected FPS is 25 (matroska 0 stream 25
 container 25 estimated 25 tick_per_frame 1 time base_ 1 / 25)
 2010-10-03 14:49:46.142 AFD: Selected FPS is 25 (matroska 0 stream 29.97
 container 25 estimated 25 tick_per_frame 1 time base_ 1001 / 30000)
 2010-10-03 14:49:57.305 AFD: Selected FPS is 25 (matroska 0 stream 25
 container 25 estimated 25 tick_per_frame 1 time base_ 1 / 25)
 2010-10-03 14:50:21.843 AFD: Selected FPS is 25 (matroska 0 stream 23.9791
 container 25 estimated 23.9791 tick_per_frame 1 time base_ 2733 / 65535)
 2010-10-03 14:50:34.256 AFD: Selected FPS is 25 (matroska 0 stream 23.9791
 container 25 estimated 23.9791 tick_per_frame 1 time base_ 2733 / 65535)
 2010-10-03 14:50:52.498 AFD: Selected FPS is 25 (matroska 0 stream 23.976
 container 25 estimated 23.976 tick_per_frame 1 time base_ 1001 / 24000)
 2010-10-03 14:51:06.641 AFD: Selected FPS is 23.976 (matroska 0 stream
 23.9791 container 23.976 estimated 23.976 tick_per_frame 1 time base_ 2733
 / 65535)
 2010-10-03 14:51:17.008 AFD: Selected FPS is 25 (matroska 0 stream 23.9791
 container 25 estimated 23.9791 tick_per_frame 1 time base_ 2733 / 65535)
 2010-10-03 14:51:26.977 AFD: Selected FPS is 25 (matroska 0 stream 25
 container 25 estimated 25 tick_per_frame 1 time base_ 1 / 25)
 2010-10-03 14:51:37.031 AFD: Selected FPS is 25 (matroska 0 stream 25
 container 25 estimated 25 tick_per_frame 1 time base_ 1 / 25)
 2010-10-03 14:51:51.846 AFD: Selected FPS is 25 (matroska 0 stream 23.9791
 container 25 estimated 23.9791 tick_per_frame 1 time base_ 2733 / 65535)
 }}}

 The async files are "PAL-Speedup" files (like most PAL-DVDs) were the
 video stream was taken from Cinema/NTSC-Source combined with PAL-Audio-
 Stream. Therefore the video stream must be played faster at 25fps to be
 sync with audio. MPlayer seems to do this always (take container value),
 but myth prefers the stream-fps which seems to be wrong.

 I will now try to prefer the container-fps for a while instead of stream
 fps and see if it works (no async files anymore)

 What i still don't understand was: why files with time_base = 1001 / 24000
 and selected fps = 23.976 are played with:

 'video_output' mean = '40010,51', std. dev. = '10190,71', fps = '24,99'

 and are perfect in sync. At a first look only files with time_base = 2733
 / 65535 are async if the stream-fps was chosen.

-- 
Ticket URL: <http://svn.mythtv.org/trac/ticket/8875#comment:10>
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