[mythtv] [mythtv-commits] Ticket #10007: Video lags audio (sync) by ~400ms on hd pvr 1212 h264 recordings (only) after firmware update.

Taylor Ralph taylor.ralph at gmail.com
Thu Nov 3 18:48:26 UTC 2011

On Thu, Nov 3, 2011 at 1:52 PM, Asher Schaffer <freedenizen at gmail.com> wrote:
> On Thu, Aug 25, 2011 at 7:53 AM,  <noreply at mythtv.org> wrote:
>> #10007: Video lags audio (sync) by ~400ms on hd pvr 1212 h264 recordings (only)
>> after firmware update.
>> -----------------------------------------+----------------------------
>>     Reporter:  gdelx001@…               |      Owner:  markk
>>         Type:  Bug Report - General     |     Status:  new
>>     Priority:  minor                    |  Milestone:  unknown
>>    Component:  MythTV - Video Playback  |    Version:  0.24.1
>>     Severity:  medium                   |   Keywords:  video lag sync
>> Ticket locked:  0                        |
>> -----------------------------------------+----------------------------
>>  This didn't happen before a recent firmware update on the HD PVR taking it
>>  from version 0xf to 0x17 (May 2009->July 2011 release date), leading me to
>>  _speculate_ that some assumptions made by MythTV about h264 streams are no
>>  longer met, that Hauppauge tightened or expanded their adherence to spec,
>>  which VLC can tolerate and MythTV can't.
>> --
>> Ticket URL: <http://code.mythtv.org/trac/ticket/10007>
>> MythTV <http://code.mythtv.org/trac>
> I confirm that this is firmware related, updated to 0x17 and the
> problem is there, reverted to an earlier version and it is fine.
> There actually appear to be 2 problems.
> I have one HDPVR attached to and RNG100 which has the problem
> described in the ticket, audio is offset by ~400ms or so, plays back
> fine in vlc, but mplayer and myth have issues.
> The other HDPVR is connect to a DCT6200, that also plays back fine in
> vlc, but with myth it stutters continuously.
> I have tested this using both vdpau and software with the same
> results, the hdpvrs are both using Component/SPDIF.  I am guessing the
> problem is either with the h264 implementation with this firmware, or
> upstream in ffmpeg.  Is there any data I can provide that would be
> helpful to localize the issue, or should I be speaking with the ffmpeg
> group?

Please, attach logs to ticket with -v playback,timestamp,extra. I'll
take a look when I have the time.


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