[mythtv-commits] Ticket #1960: patch for wraptimecode - fix multiple 'Guessing avsync'

[MythTV]

#1960: patch for wraptimecode - fix multiple 'Guessing avsync'
----------------------------------------+-----------------------------------
 Reporter:  mythdev at penyball.cix.co.uk  |       Owner:  ijr 
     Type:  patch                       |      Status:  new 
 Priority:  minor                       |   Milestone:  0.20
Component:  mythtv                      |     Version:  head
 Severity:  low                         |  
----------------------------------------+-----------------------------------
 I've just had a period where on change to some lower resolution dvb
 channels  I was getting bad stuttering and the logs had multiple 'Guessing
 at new AV sync values' messages which originate in
 NuppelVideoPlayer::WrapTimecode.
 I added a debug printout to show the values of
 timecode,lastval[TC_AUDIO],tc_wrap[TC_AUDIO], lastval[TC_VIDEO]and
 tc_diff_estimate. This showed that the AUTO_RESYNC code was effectively
 doubling what should be the value of tc_wrap - leading to the Guess being
 invoked every 30 calls. The attached patch fixes this.

 Note that the value of TC_WRAP can be negative (with or without the patch)
 and I think this means that there is a corner case where the initial 'wrap
 test'
 {{{
 // wrapped
 if (timecode < tc_lastval[tc_type] - 10000)
 }}}
 is triggered when it shouldn't be - I only got this behaviour once in a
 few hundred channel changes.

-- 
Ticket URL: <http://svn.mythtv.org/trac/ticket/1960>
MythTV <http://www.mythtv.org/>
MythTV