[mythtv-users] Aspect ration wierdness?

richard Woelk richardwoelk at gmail.com
Fri Sep 10 13:38:32 UTC 2010

  On 09/07/2010 14:17, Jan Johansson wrote:
>> It does sound like the STB is putting out something funky.  One final
>> sanity check I would recommend is playing the file back in mplayer and
>> seeing how it is handled there.  I assume you will get the same result
>> and myth is giving, which would indicate that it is indeed a STB
>> issue.
> Mplayer gives the same result.
>> Any chance of getting a new STB?
> Nope.
>> Also, how are you capturing?
> STB SCART ->  Composite adapter ->  PVR 350 (same cabling as for old STB).
> As I said, my plan is to get a HD PVR and use component instead, but that is for another day.
> Actually, I have to put the entire troubleshooting on ice for a bit, as I am off for a little trip.
> Thanks so far!

Is your set top box HD? If so, it might be outputting anamorphic. When you hooked it to 
the TV, did you hook directly to the SCART or use composite?
There is a signal similar to Closed Caption/teletext that can be used for auto-stretch 
that your TV might be accepting but not the PVR350. Does this happen on certain channels only?

I have HD satellite, and I set the STB to output anamorphic on the HD channels to my 
PVR-250 in widescreen. The ivtv driver has an option to change the aspect.
 From my channel change script, I launched another script into the background that checks 
the channel, waits 3 seconds, then changes the aspect. This puts a "widescreen" flag in 
the mpeg2 stream that mythtv playback follows properly. In my case, the widescreen 
channels are between 200 and 299.

-------------from channel.pl-------------------------

system ("/usr/local/bin/video_settings3 $channel &");


# - for pvr-250
sleep 3


#if (( $channel > 200 && $channel < 299 )); then
#   /usr/bin/v4l2-ctl -d /dev/video-SD -c video_aspect=2
    /usr/bin/v4l2-ctl -d /dev/video-SD -c video_aspect=1

I hope this works for you

- Richard

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