[mythtv-users] Strange resolution problem

[Damian]

On 14/07/2015 23:07, Damian wrote:
> On 07/07/2015 09:46, Damian wrote:
>> On 06/07/2015 16:01, Michael T. Dean wrote:
>>> On 07/06/2015 06:32 AM, Damian wrote:
>>>> The first thing I did was test a particularly bad scene from a 
>>>> program I watched a few nights ago. That would now play without any 
>>>> problems. So, I decided to watch a full film last night. It was 
>>>> pretty good throughout, but at about 3 points throughout the film, 
>>>> it had two or three of these 'black and searching' screens, then 
>>>> after a couple of seconds it pops back up having found the 
>>>> resolution again (switching between 1920x1080 and 1919x1080). 
>>>
>>> The fact that the annoying mode is 1 pixel less than your 
>>> normal/desired mode leads me to assume that this may be related to 
>>> the Window Manager you're using "scaling away" some 1-pixel-wide 
>>> auto-hidden bar on the side of your screen every once in a while. 
>>> I'd guess it's one of those fancy, compositing Window Managers. That 
>>> said, if I'm correct, it won't help you fix the issue with your 
>>> projector disliking mode changes (and/or prevent mode changes), but 
>>> it may help find ways to avoid the changes (even it means just 
>>> switching to a different, 
>>> less-fancy-but-much-better-for-MythTV-type-usage Window Manager).
>>>
>>> Note, too, that MythTV will only change the mode if you enable:
>>>
>>> Separate video modes for GUI and TV playback
>>> Switch X Window video modes for TV. Requires "xrandr" support.
>>>
>>> and set the appropriate related settings.  So, if your mode is 
>>> changing and you have that disabled, it's not MythTV that's doing 
>>> the changing.
>>>
>>> Mike
>>
>> I fixed it!
>>
>> I too was thinking that it must be something to do with the window 
>> manager or something, but I'm using XFCE, the default WM that comes 
>> with Mythbuntu.
>>
>> Then I remembered that I edited the DPI setting to make everything a 
>> bit bigger on screen.
>>
>> I had it set to 100, which must have resulted in things not quite 
>> fitting to 1920x1080 right. So, it was kind of flickering between 
>> 1920 and 1919 resolution.
>>
>> I'm not quite sure why this was only happening on scene changes, but 
>> don't really care as it's fixed now :-) I've even deleted the xorg 
>> file (why had been the only thing that had made it at all bearable) 
>> and all is still good.
>>
>> Thanks for the help everyone.
>>
>> Is there any other way to make everything a bit bigger on screen 
>> without messing with the DPI? I've increased the default font size 
>> and the height of the default mythbutu/xfce panel, but some things 
>> are still too small.
>>
>> Thanks again,
>> Damian
> Here's part of the output of ... xrandr -q --verbose
>
> 1920x1080 (0xb9)  172.8MHz -HSync +VSync *current
>         h: width  1920 start 2040 end 2248 total 2576 skew    0 
> clock   67.1KHz
>         v: height 1080 start 1081 end 1084 total 1118 clock 60.0Hz
>   1920x1080 (0xba)  148.5MHz +HSync +VSync
>         h: width  1920 start 2008 end 2052 total 2200 skew    0 
> clock   67.5KHz
>         v: height 1080 start 1084 end 1089 total 1125 clock 60.0Hz
>   1920x1080 (0xbb)  148.5MHz +HSync +VSync
>         h: width  1920 start 2448 end 2492 total 2640 skew    0 
> clock   56.2KHz
>         v: height 1080 start 1084 end 1089 total 1125 clock 50.0Hz
>   1920x1080 (0xbc)  148.4MHz +HSync +VSync
>         h: width  1920 start 2008 end 2052 total 2200 skew    0 
> clock   67.4KHz
>         v: height 1080 start 1084 end 1089 total 1125 clock 59.9Hz
>   1920x1080i (0xbd)   74.2MHz +HSync +VSync Interlace
>         h: width  1920 start 2008 end 2052 total 2200 skew    0 
> clock   33.8KHz
>         v: height 1080 start 1084 end 1094 total 1125 clock 60.1Hz
>   1920x1080i (0xbe)   74.2MHz +HSync +VSync Interlace
>         h: width  1920 start 2448 end 2492 total 2640 skew    0 
> clock   28.1KHz
>         v: height 1080 start 1084 end 1094 total 1125 clock 50.0Hz
>   1920x1080i (0xbf)   74.2MHz +HSync +VSync Interlace
>         h: width  1920 start 2008 end 2052 total 2200 skew    0 
> clock   33.7KHz
>         v: height 1080 start 1084 end 1094 total 1125 clock 60.0Hz
>
> From that list, this one ...
>   1920x1080 (0xba)  148.5MHz +HSync +VSync
>         h: width  1920 start 2008 end 2052 total 2200 skew    0 
> clock   67.5KHz
>         v: height 1080 start 1084 end 1089 total 1125 clock 60.0Hz
> ... looks most like the settings I need for my projector at 1920x1080 
> (67.5 H-freq and 148.5 Pixel Frequency)
>
> How can I make the machine use this setting instead of the 'current' 
> one it is using?
>
> I assume I need to make a modeline out of those numbers, bot how do I 
> do that?
>
> Damian

OK, I'm assuming that this is the aswer:

# 1920x1080 @60Hz 67.5KHz 148.5MHz +HSync +VSync
Modeline "1920x1080" 148.5 1920 2008 2052 2200 1080 1084 1089 1125 
+HSync +VSync

I'll give it a try tomorrow

Damian