Those 1024x768 16:9 sets are weird because the pixels are not square or 4:3- the pixels themselves must be rectangular or about 1.78:1.


You need to tell Xorg your pixel aspect ratio. I have never done this, but a quick Google search turned up-

http://www.mythtv.org/wiki/Aspect_ratio


* The Aspect ratio can be set using the DisplaySize in xorg.conf using Height Wide (mm) eg DisplaySize 656 369 (16:9 ratio- Widescreen)

* With Xorg 7.2, MythTV detects Xinerama as being active at all times and so will ignore the display sizes when calculating the aspect ratio for displaying video. To fix this, use the following SQL command:


UPDATE settings SET data = '1.7777' where value = 'XineramaMonitorAspectRatio' AND hostname='yourhost';


depending on if you're using Myth or not.



Here is exactly what you need to do:

http://www.mythtv.org/wiki/Display_Size


Calculating your own values


If you have non-square pixels on your device (i.e. if the ratio of your physical display's dimensions is different from the ratio of your X and Y resolution), and you would like to run X at about 100DPI (to size fonts appropriately in programs other than MythTV), you will need to set either vertical or horizontal pitch to 100DPI and calculate the other based on your physical display's dimensions. Generally, you should choose to use 100DPI vertical pitch.


So, for example, if you're using a 16:9 CRT TV using TV out at 800x600, to choose to use 100DPI vertical pitch, you should start with the size specified above ("DisplaySize 203 153"), but calculate the first value based on the TV's aspect ratio. To do so, divide 153 by 9 and multiply by 16 to get 272. Therefore, you would use the line


1. For 800x600 at 100dpi (16:9)


DisplaySize 272 153


Note, also, that a 4:3 monitor using 1280x1024 pixels (5:4) is using non-square pixels.


See also the FAQ for more details and for information about setting DPI when using NVIDIA drivers.


If your display is using a resolution not listed above, it's very easy to compute the values you need for DisplaySize. Use "DisplaySize x y" where


x = (horizontal resolution)*0.254


and


y = (vertical resolution)*0.254


both rounded to the nearest integer. Again, the physical display's aspect ratio should be considered for non-square pixels.



For 1024x768, this would be


x=1024*0.254, or x=260


and


y=768*0.254, or y=195


so you would use "DisplaySize 260 195".


Also
http://wiki.x.org/wiki/DisplaySize

 

Seems very confusing, but I will read through it thoroughly after work.

From what I've gathered though it seems that I need to change what is called 'Display Size' to a 16:9 ratio, that will then output a 16:9 image but in the 1024x768 resolution????

Hopefully I can figure out how to properly edit my xorg.conf file since I was having problems before.

Also I am not using Myth TV, never really tried it either. Again I am new to HTPC and Linux for the most part. I've just been playing videos I've downloaded with vlc, maybe i'll look into myth tv after I get this sorted. Thanks.

 

I've have two sets that are native 1024x768. On one of them I use the VGA input and to get rid of the similar issues you are dealing with I use the 1280x768 resolution which it accepts, and everything is fine. No overscan on the VGA input.


On my other 1024x768 I give it 720p through the HDMI input. There is overscan ( which is most likely responsible for your image being too large for screen) but since I primarily use mythtv I can manually adjust for the overscan (mythtv has controls to adjust for the overscan).. What you may need to do is see if your TV has a setting to turn the overscan off. I have a Samsung which has a mode called "Just Scan" which turns off overscan through the HDMI port.

 

unfortunatly my vga port will not accept any 16:9 resolutions just 4:3 resolutions like 1024x768 and lower. Any other resolution puts the tv in a standby no signal mode.

I will look into the just scan option on my television when it is in a 720p resolution. I think I can set my card to 1024x720.

I will look on my lunch break.

The only reason this is really an issue is for viewing images and flash videos. Both of which look "fat" right now under the current settings.

 



Quote:
Originally Posted by jstnhickey /forum/post/15974934


Seems very confusing, but I will read through it thoroughly after work.

From what I've gathered though it seems that I need to change what is called 'Display Size' to a 16:9 ratio, that will then output a 16:9 image but in the 1024x768 resolution????

Hopefully I can figure out how to properly edit my xorg.conf file since I was having problems before.

I have never tried changing the DisplaySize parameter in my xorg.conf file, but my take on the citation in my previous post is that you just have to paste this into your xorg.conf file (in the correct location):


DisplaySize 260 195


The two numbers are the horizontal and vertical DPI settings. These values together set the pixel aspect ratio correctly so that 1024x768 will display without distortion on a 16:9 montor/TV, which is your goal.


Normally, the H and V DPI's are the same for most displays whose pixel counts, when divided, equal the aspect ratio of the monitor.


1024/768 does not equal 1.78, so you must have unique DPI's for the horizontal and vertical dimensions.

 

Didn't get a chance to go home for lunch.

Quote:
The two numbers are the horizontal and vertical DPI settings. These values together set the pixel aspect ratio correctly so that 1024x768 will display without distortion on a 16:9 montor/TV, which is your goal.

Does this mean that it will be an image that leaves the black bars on the side? or are you saying that it will somehow display 1024x768 in 16:9 without it being squished down? To me that doesn't really make sense, but then again I'm pretty lost at this point with this stuff.... Never really delt with pixels, resolution, etc.

Quote:
1024/768 does not equal 1.78, so you must have unique DPI's for the horizontal and vertical dimensions.

I have read on some other websites that 42in plasmas are unable to show 720p exactly because of some measurment constraints that is why many 42in plasmas are 1024x768. The pixels don't fit right otherwise or something along those lines


I'll try out all of these options after work.

 



Quote:
Originally Posted by jstnhickey /forum/post/15975533


unfortunatly my vga port will not accept any 16:9 resolutions just 4:3 resolutions like 1024x768 and lower. Any other resolution puts the tv in a standby no signal mode.

I will look into the just scan option on my television when it is in a 720p resolution. I think I can set my card to 1024x720.

I will look on my lunch break.

The only reason this is really an issue is for viewing images and flash videos. Both of which look "fat" right now under the current settings.

I'm going to download your user manual and take a look... My first thought is that you should try regular 720p (1280x720) and then turn off the overscan. The TV is probably optimized for scaling 720p since that is a resolution most other device types might send to it.


I want to make sure it is overscan that is your problem though... Is it just a few pixels cut off from the edges (like you can't see all of the panels on the desktop) or is there a lot more that is missing?

 

Browsed through your manual. A couple of things I noticed:


1. Your TV does have a "Just Scan" mode like my samsung. It's in the menu, or you can use the P.size button on the remote. I suggest giving it 1280x720 and using this mode. You can move the picture around if it is just offset...


2. Your 1024x768 picture may look bad because of the "zoom" mode you are using. Try cycling through them (P.size button again)


3. the larger version of your set lists 1360x768 as an optimal mode that it will accept via VGA or HDMI, but not for your size set. However, I have a Westinghouse that doesn't list 1366x768 as an mode it accepts, but it's larger version does. And in fact, I can give my Westinghous 1366x768 anyway, via VGA. Might require a custom modeline, however...


good luck.

 

I'm not disagreeing with RGB's method, it might work - but you shouldn't have to do it. Your TV's native resolution is 1024x768, so every signal it gets it ends up turning it into 1024x768 before displaying it (thus RGB's statement that you have rectangular pixels - that's how you get the 16:9 display with a 4:3 native resolution). So it should be able to appropriately display an input that matches it's native resolution in widescreen as well...


This is not a knock on RGB's suggestion, just an observation/frustration with TV sets.


Another thing to try is giving it 1024x768 and putting it in just scan mode...

 

Putting the TV in just scan mode and putting the computer in 1280x720 worked. Only about 5 pixels are cut off.

The picture is fairly crappy though...

 



Quote:
Originally Posted by jstnhickey /forum/post/15978689


Putting the TV in just scan mode and putting the computer in 1280x720 worked. Only about 5 pixels are cut off.

The picture is fairly crappy though...

That overscan is minor enough to adjust with xvidtune. A good howto for this is on the lower section of this page --> http://howto-pages.org/ModeLines/


Can you elaborate on "fairly crappy"?

 

I messed with the contrast and sharpness and it looks a bit better. I don't know how to describe the crappiness it was kind of blury and the colors looked to run a bit on words. I'm going to use the computer for a few days and see what other changes I should make.

Should I maybe try adding a lower 16:9 resolution to my xorg.conf file and trying that.

 



Quote:
Originally Posted by jstnhickey /forum/post/15979205


I messed with the contrast and sharpness and it looks a bit better. I don't know how to describe the crappiness it was kind of blury and the colors looked to run a bit on words. I'm going to use the computer for a few days and see what other changes I should make.

Should I maybe try adding a lower 16:9 resolution to my xorg.conf file and trying that.

Yours is going to take some work...increasing the DPI to 120 should help. To see what it's running at now, run this from a terminal:
Code:

xdpyinfo | grep resolution

Also check the display size it's using:
Code:

xdpyinfo | grep dimension

And see what modes are being detected:
Code:

xrandr

You can never have too much info about what X is doing.

With the nvidia card, you should be able to change the DPI in the "Screen" section for yor TV in xorg.conf by adding:
Code:

Option "DPI" "120 x 120"

Note that this may not be 100% correct (120 x 120) in your circumstance, but it's worth a shot as it can't hurt anything.


Save, restart X, then check the DPI with xdpyinfo again as noted above. If it didn't take, you may also have to add the following to the "Screen" section and restart X again:
Code:

Option "UseEdidDpi" "false"

If the DPI doesn't change after that or it still looks crappy, you'll probably have to use Rgb's calculation method to get more accurate results.


Nothing wrong with playing around with different modes, either.

 

Hmm for some reason everytime I reboot the resolution gets set back to 1024x768. Looks like I'll try RGBs method, definitely not today, though, not in the mood to mess with the computer all day.