[vdr] FF card AV sync problems, possible fix to VDR

VDR User user.vdr at gmail.com
Wed Jan 31 19:45:23 CET 2007

On 1/31/07, Klaus Schmidinger <Klaus.Schmidinger at cadsoft.de> wrote:
> Ville Rannikko wrote:
> > Hi!
> >
> > The newest firmware for FF cards did not completely fix the AV desync
> > problems for me. According to information from Werner the problem
> > happens when small video frames fill the decoder buffer with over 2
> > seconds of data. So I made this patch for dvbplayer.c to stop it from
> > uploading more PES frames to decoder when STC/PTS difference is more
> > than 2 seconds. This seems to fix the remaining problems for me, but I
> > have not tested it much. The PTS/STC-code has been mostly taken from the
> > dvb-subtitles plugin. Comments, please
> While this may actually help in your case, I'm not particularly fond
> of this. The cDvbPlayer shouldn't have to worry about this. It takes care
> that data is sent to the player device fast enough to avoid underruns,
> but that's all it should have to care about. It's the device's (driver
> and firmware) job to play the data correctly.

>From what he's saying, the problem is buffer overrun's, not underrun's.  Too
much data is being sent and the device isn't able to keep up.  If that's the
case then it would make sense for vdr to have a user setting to limit how
many seconds (or milliseconds perhaps?) worth of data is sent to the
buffer.  I can't think of any reason not to add such a feature if it means
better usability for the end-user.

That's my opinion anyways.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://www.linuxtv.org/pipermail/vdr/attachments/20070131/388d0c65/attachment-0001.htm

More information about the vdr mailing list