[mythtv-users] "/ try to find video override mode" Change of resolution to match 720x576 and 720x480 ?

[John]

I have been trying for a while to get mode switching to work properly, 
as I have both PAL (720x576i) and NTSC (720x480i) DVD isos on my myth 
box. There seems to be no simple way to play back the DVDs at the right 
resolution, and at the right rate.

I am most interested in changing the refresh rate, to reduce scan 
juddering, and I'm happy to let myth do the scaling if needs be, but 
even that doesnt workout of the box.

I am running VGA to Scart, and have good modelines for both 720x480, and 
720x576 interlaced on a CRT TV.

Couple of issues:

I am running 22fixes, and as far as I can see, the

"// try to find video override mode " _never_ finds any matching modes 
for the played video, whatever you put in the specific modes fields. It 
always defaults to the top line video mode defined next to the GUI 
display resolution. I have followed advice to disable twinview, so that 
the interlaced modes are displayed, and the modes can all be selected as 
the defaults in the top line.

The refresh matching works, but only for the same resolution. As I cant 
drive the TV at 720x576 30i, this is not an option.

I can manually use xrandr to switch modes, so that is not the issue. A 
simple script that ties a remote button to either xrandr -s 720x576 or 
xrand -s 720x480 works, but you need to restart mythtvfrontend to pick 
up the change in "display window".

I also found that unfortunately xrandr doesnt seem to let you set the 
aspect ratio via the displayscreen or dpi options. The options are in 
the man page, but when aplied seem to make no diffrence on my NVidia 
6200. Therefore I have a default of 70 x 100 dpi set to make sure 
720x576 is not scaled on my 16:9 screen, with 16:9 content, switching to 
720x480 changes the aspect ratio of the display window, and therefore 
Myth scales the Video, and doesnt fill the screen.

I have a working solution now, which was to craft a 600x480 modeline, 
which matches the aspect ratio of 720x576.


However, its all a bit clunky.


As you can see I've spent more time than it deserves on this problem :-) 
Is anybody successfully using the override modes succesfully in 
0.22-fixes ? If so is there some trick I'm missing ?

Best regards,

John