[mythtv-users] Video quality?

[Kevin Page]

On Mon, 2007-10-01 at 13:30 +0100, Mark Kendall wrote:
> I'd put my house on deinterlacing being the major problem. The other
> issue is probably the refresh rate on your monitor.
> 
> Your monitor is probably defaulting to 60Hz (most seem to)
[snip]
> You may be able to force the monitor to accept a 50Hz modeline 

Of course, this would make sense. Thanks! My monitor is indeed stuck at
60Hz.

> - I managed with my Dell.

Any hints? I also have a Dell - a 2407fpw. I've tried feeding it various
modelines but it always auto-adjusts to 60Hz (whilst accepting the
resolution). I'll dig out a VGA cable later and see if the 60Hz-only
refresh is a DVI thing.

The panel reports what it's running at (and scaling the xorg.conf
resolution to) on DVI (it's always @60Hz!), but doesn't give anything
away when it has composite input from the STB, which I presume is
PAL/50Hz.

I suspect I could be out of luck for 50Hz - the specs say 56-76Hz is
supported, and Xorg.log shows:
Ranges: V min: 56  V max: 76 Hz, H min: 30  H max: 83 kHz, PixClock max 170 MHz

I wonder whether 75Hz might be "better"?

> Your monitor is probably defaulting to 60Hz (most seem to) which will
> never give you smooth playback of PAL material with Mythtv at the
> moment.

I'm intrigued (hopeful?) by "at the moment". Or is our only hope a
deinterlacing algorithm incorporating framerate adaption as you
describe?

> Other solutions seem to have the capability to alter the
> framerate while deinterlacing (e.g. some Windows apps, Playstation 3)
> but mythtv in its current state does not attempt it.

Regards,

kev.