Hi,
Cristiano wrote:
> I am having some problem with vdr xine and analogtv plugin.
>
> I have a client-server vdr installation based on vdr 1.3.34, xine 0.7.6
> plugin, when I select a DVB channel I have no problems but if I select
> an analog channel (stream generated by analogtv plugin 0.9.37 with ivtv
> 0.4.0 and PVR 150 card) I had some sync problem: here is the xine log:
>
> audio jump, diff=-51840
> audio_out: inserting 27627 0-frames to fill a gap of 51815 pts
> video jump
> bad_frame
> video jump
> video jump
> bad_frame
> video_out: throwing away image with pts 653020 because it's too old
> (diff : 6489
> 9).
> 200 frames delivered, 14 frames skipped, 1 frames discarded
> video_out: throwing away image with pts 2753839 because it's too old
> (diff : 418
> 6).
> bad_frame
> bad_frame
> video jump
> bad_frame
> bad_frame
> audio jump, diff=-51850
> audio_out: inserting 27655 0-frames to fill a gap of 51866 pts
> video jump
> bad_frame
> video jump
> bad_frame
> bad_frame
> 200 frames delivered, 7 frames skipped, 1 frames discarded
> video_out: throwing away image with pts 5052089 because it's too old
> (diff : 4544).
> 200 frames delivered, 0 frames skipped, 1 frames discarded
> bad_frame
> audio jump, diff=-45370
> audio_out: inserting 24197 0-frames to fill a gap of 45382 pts
> video jump
> video jump
> video jump
> bad_frame
> video_out: throwing away image with pts 6157260 because it's too old
> (diff : 54139).
>
> Searching on the vdr mailing list I found a thread ("problem
> vdr-xine-0.7.3 plugin") that seems to be related to this issue.
> I tried to "play" with WRAP_THRESHOLD values without good results
>
> Did you have any suggestion?
Have a look into xineDevice.c, cXineDevice::PlayCommon3() and comment
out the first "if (0)" (i. e. => "// if (0)"). This enables logging of
PTS values on console and you can check the offset between audio and
video PTS as well as the offset to xine's metronom.
The offset to xine must allways be positive and should be around 60000
pts (= 2/3 seconds). If it gets too small or even negative, then xine
will get buffer underruns which may cause the above issue.
Another parameter to play with is vdr-xine's prebuffer setting. If you
enlarge the setting then the above offset to xine should enlarge, too.
But there are some drawbacks: when VDR cannot dispose its data to the
device, it clears the device (after consecutive poll timeouts) which
discards the buffers and causes vdr-xine to setup the prebuffer again
and again.
Especially the analogtv plugin uses "little" buffers for the encoder and
therefore it is likely that vdr-xine's prebuffering overflows the
encoder buffers which are then in turn cleared. The result is that there
is almost no buffer although vdr-xine thinks to have a reasonable sized
one (it's on my todolist to change prebuffering to consider xine's
metronom).
For any reason (I still haven't discovered why) there is a difference in
the achieveable buffer size when xine is already connected to vdr-xine
and you switch to an analogtv channel respectively when xine connects to
vdr-xine after VDR was tuned to the analogtv channel. Most often the
latter works without the above mentioned issue.
Bye.
--
Dipl.-Inform. (FH) Reinhard Nissl
mailto:rnissl@xxxxxx
