How to set resolution with non 1:1 aspect ratio

sangeetk · 10-08-2009, 02:23 PM

Hi,

I am a newbie and this is my first question in this linux forum.
I am facing difficulty in getting 16:9 resolution from my old laptop with Intel® 82852/82855 GM/GME Graphics controller.

The problem goes like this:

My laptop (which is without screen) supports the following resolutions:
640x480, 800x600, 1024x768 and also few other standard resolutions, but it doesn't support 800x480.

I am using the laptop as a carputer and Xenarc 700TSV touchscreen as screen, which is of 16:9 ratio and the native resolution is 800x480.

Now the problem is my old laptop doesn't support 800x480 and It is not possible to upgrade the graphics card. The closest resolution supported by the laptop is 800x600 but the output is horizontally stretched.

Is it possible to vertically stretched the desktop resolution so that when I use 800x600, it actually displays 800x480 pixels after vertical scaling?

And when I see this 800x600 output in my Xenarc 7 inch screen, output is horizontally stretched and aspect ratio becomes 1:1 ?

Any thoughts ??

lutusp · 10-08-2009, 02:31 PM

Quote:

Originally Posted by sangeetk

Hi,

I am a newbie and this is my first question in this linux forum.
I am facing difficulty in getting 16:9 resolution from my old laptop with Intel® 82852/82855 GM/GME Graphics controller.

The problem goes like this:

My laptop (which is without screen) supports the following resolutions:
640x480, 800x600, 1024x768 and also few other standard resolutions, but it doesn't support 800x480.

I am using the laptop as a carputer and Xenarc 700TSV touchscreen as screen, which is of 16:9 ratio and the native resolution is 800x480.

Now the problem is my old laptop doesn't support 800x480 and It is not possible to upgrade the graphics card. The closest resolution supported by the laptop is 800x600 but the output is horizontally stretched.

Is it possible to vertically stretched the desktop resolution so that when I use 800x600, it actually displays 800x480 pixels after vertical scaling?

And when I see this 800x600 output in my Xenarc 7 inch screen, output is horizontally stretched and aspect ratio becomes 1:1 ?

Any thoughts ??

If you edit /etc/X11/xorg.conf and put in the resolution you want, and if your video adaptor can produce that resolution, then you can have it.

Google for topics related to "X windows configuration" and the like.

Chromezero · 10-08-2009, 04:26 PM

If your video card does not support that resolution, you may be out of luck. However, you may be able to set your resolution to a higher res., wide screen format and push that out to the monitor. The native resolution of a monitor is not always the maximum limit of a monitor. However, I'd recommend checking the documentation of your monitor before attempting this.

sangeetk · 10-09-2009, 06:38 AM

My video card supports 1280x768 resolution but it is too difficult to operate with fingers on touchscreen. What I thought if it is possible to render the 800x480 pixels in 800x600 resolution after vertical scaling?

-SangeetK

jschiwal · 10-09-2009, 06:48 AM

Try to create a custom modeline with the "gtf" program. At it to the [Modes] section. If the modes section doesn't exist, add it to your "Monitor" section. Also add the resolution label to the Modes line in the screen section.

Here is a part of my laptop's "Screen" section. I just use "1440x900", so it is first. You want "800x480" there instead (if your touch screen info is accurate).

Code:

Section "Screen"
  DefaultDepth 24
  SubSection "Display"
    Depth      15     
    Modes      "1440x900" "1366x768" "1360x768" "1280x800" "1152x864" "1280x768" "1280x720" "1024x768" "1280x600" "1024x600" "800x600" "768x576" "640x480" 
  EndSubSection                                                                                                                                            
  SubSection "Display"                                                                                                                                     
    Depth      16                                                                                                                                          
    Modes      "1440x900" "1366x768" "1360x768" "1280x800" "1152x864" "1280x768" "1280x720" "1024x768" "1280x600" "1024x600" "800x600" "768x576" "640x480" 
  ...
                                                                                                                                    
  Device       "Device[0]"                                                                                                                                 
  Identifier   "Screen[0]"                                                                                                                                 
  Monitor      "Monitor[0]"                                                                                                                                
EndSection

This is what my "Monitor" and "Modes" sections look like:

Code:

Section "Monitor"
  Option       "CalcAlgorithm" "XServerPool"
  DisplaySize  332 187                      
  HorizSync    50-70                        
  Identifier   "Monitor[0]"                 
  ModelName    "1440X900@60HZ"              
  Option       "DPMS"                       
  Option       "PreferredMode" "1440x900"   
  VendorName   "--> LCD"                    
  VertRefresh  50-60                        
  UseModes     "Modes[0]"                   
  Gamma   1.15  1.15  1.15  # created by KGamma
EndSection                                     


Section "Modes"
  Identifier   "Modes[0]"
EndSection

Chromezero · 10-09-2009, 10:26 AM

It sounds as if his video card won't support a resolution this small but it would be worth trying I guess.