[mythtvnz] Pixellation Every ~ 20 minutes

[Stephen Worthington]

On Tue, 16 Oct 2012 19:44:50 +1300, you wrote:

>...now.......
>what has changed in the video encoder/decoder software to cause this I wonder?  
>Anyone tried changing their video acceleration to see if this changes anything?
>ie VDPAU settings.  Who's brave enough to try rolling back to XvMC to see if SD is OK?
>

Have you tried playing the recording files on another player (eg VLC,
which has all the codecs internally), or on another PC?  That should
rule out the playback software and leave only the recording software
as a problem.

In recording DVB-T, there is no encoding being done - the packets for
that program's streams are just selected out of the full set of
packets for the multiplex, and then they are written directly to disk.
So the corruption would have to already be in the packets being read
from the tuner (ie a reception problem), or in the software selecting
and buffering the packets to write them to disk.  An overflow in the
buffers waiting to be written is the most likely idea.  But that
should affect all tuners, or all tuners writing to that disk, not just
your particular model of tuner.  So we need to keep on narrowing down
the possibilities as much as possible.

Another useful check would be if you could borrow a different tuner
from someone and try with that.

If the problem can be narrowed down to a recording problem it would
then be useful to run mythbackend with high debugging settings.  It is
best to do this as a test only, as too much logging can itself cause
problems with recordings - it needs to have the recording going to a
different disk from the log files, and only your test recording
happening.