[mythtv-users] Scaling HD output

Seth Heckard seth.lists at gmail.com
Mon Nov 7 18:08:15 EST 2005

I have a HD tube TV (Sanyo HT32744) which is 1080i native but supports
720p via upconversion.  Attached to it I have my Myth computer with a
FX5200 outputting to DVI, and then connecting to my TV via a HDMI

Now, in my area ABC and Fox are 720P.  I have a 1280x720 modeline that
works perfectly and allows me to watch the recorded shows in full
glory.  There's no problem there.

My problem is with 1080i broadcasts.  I can't get a
1920x1080i/1920x540 modeline to work to save my life, as I get a
picture with too much flashing and artifacts.  So, I've decided while
not ideal, in order to get a working picture I'd like to be able to
have Myth scale 1080i content to a 1280x720 output.  It seems like
this should be possible, but I can't get it to work.  All it does is
output the 1080i signal sans scaling, which chops off a third or so of
the image to the right.

Is there any way to have Myth scale down 1080i output?  Or is this
something that is not possible.  If it is possible, how do I go about
enabling it?

Also, I have been having problems triggering the automatic resolution
switching for 1080i broadcasts.  It doesn't seem to work, as if the
file is not being recognized as 1920x1080, which is the size I have
set in the config.  Viewing the verbose mythfrontend output, I see a
few references to 1920x1088 while playing the file.  Where are the
other 8 pixels coming from, and is this possibly why the resolution
switching is failing?  If I open the file in mplayer or xine it
reports as 1920x1080.

Thanks, Seth

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