Aspect ratio incorrect on 16:10 LCD screen

[Agamemnon]

I am using the GB-PVR (PVRX2) software with a Hauppauge WinTV Nova-TD stick and a 20" Samsung 16:10 LCD monitor set to 1680x1050 resolution but the PVRX2 refuses to display 16:9 or 4:3 material correctly because it assumes that my monitor aspect ratio is 16:9 when in fact it is 16:10 and uses square pixels as are most widescreen monitors, and therefore narrows the TV image assuming the monitor will stretch it, which it won't do because it uses square pixels.

Can this problem be fixed so that programmes display with the correct aspect ratio of 16:9 or 4:3 on 16:10 monitors which use square pixels?

[sub]

The default settings are only aimed at 16:9 or 4:3 screens. If these dont suit you, then you tweak the values in the <AspectRatioModes> section of the config.xml file.

[Agamemnon]

I don't understand what the settings mean. The programme assumes rectangular pixels therefore setting the TvShape displays a 16x10 window. If I set the TvShape to 16:10 it still displays a 16:10 window but with black bars top and bottom and a letterbox in the centre which is far too narrow. The ratios in the AspectRatioModes settings don't make any sense to me. They look more like coordinates than ratios. How do I get the main window to display with a 16x9 aspect ratio using square pixels. Can someone explain what the settings mean?

Nearly all widescreen monitors at 16:10 ratio so why doesn't GB-PVR support that ratio? The previous version of the programme with the old UI use a window which could be resized by the user independently in the X and the Y direction but the PVRX2 application won't allow that. It's always 16:10.



<!-- Aspect Ratio settings -->
<TvShape>16x9</TvShape>
<AspectRatioModes>
<AspectRatioMode name="Auto" ratio="0,0,0,0" />
<AspectRatioMode name="Fill" ratio="0,0,1,1" />
<AspectRatioMode name="LetterBox" ratio="0,0.125,1,0.875" />
<AspectRatioMode name="Remove LetterBox" ratio="0,-0.125,1,1.125" />
<AspectRatioMode name="Center Cut" ratio="-0.05,-0.17,1.04,1.17" />
<AspectRatioMode name="PillarBox" ratio="0.08,0,0.92,1" />
</AspectRatioModes>

[Freakitchen]

This old thread of mine might help you, assuming that the methods still work the same.

http://forums.nextpvr.com/showthread.php?t=18122

[sub]

<TvShape>16x9</TvShape>
<AspectRatioModes>
<AspectRatioMode name="Auto" ratio="0,0,0,0" />
<AspectRatioMode name="Fill" ratio="0,0,1,1" />
<AspectRatioMode name="LetterBox" ratio="0,0.125,1,0.875" />
<AspectRatioMode name="Remove LetterBox" ratio="0,-0.125,1,1.125" />
<AspectRatioMode name="Center Cut" ratio="-0.05,-0.17,1.04,1.17" />
<AspectRatioMode name="PillarBox" ratio="0.08,0,0.92,1" />
</AspectRatioModes>

If you set the tv shape to 16x9, and the aspect ratio mode to 'auto', then it'll use the settings defined for 'fill' when you play 16:9 content and 'PillarBox' when you play 4:3 content. You can modify the 'fill' and 'PillarBox' ratio mode settings in config.xml with the appropriate values for your screenshape. 0,0 is the top/left. 1,1 is the bottom/right. Do the math work out the appropriate numbers, then plug them in and you sorted.

If you do it, also post the settings for the benefit of any future 16:10 user wanting the same thing.

[Agamemnon]

Thanks, but the figures given even when the are corrected to <AspectRatioMode name="Fill" ratio="0,0.05,1,0.95" /> do not actually solve the problem. What happens is that image is no longer being overscanned properly in the vertical direction like it's supposed to be. Instead the vertical is not ovescanned at all so you see black lines at the top bottom and then scan lines from the top and bottom of the TV image that are not supposed to be displayed on screen and lots of stuff is missing from the horizontal, left and right of the image.

PVRX2 has been programmed to regard monitor aspect ratios incorrectly. The only way to fix PVRX2 is to programme the software to always use square pixels. It assumes that the screen ratio is 16:9 even when the graphic's card resolution is set to 16:10 and therefore concludes that it should use rectangular pixels so displays a 16:10 window instead of a 16:9 window thinking it will be stretched to 16:9 by the monitor. Whoever programmed it does not understand that almost all LCD computer monitors use square pixels and a 16:10 graphics resolution such as 1680x1450 is mapped onto a 16:10 screen. This is clearly a bug. All 16:10 computer monitors use square pixels. I suspect that this bug would also manifest itself for people using LCD monitors with resolutions such as 1280x1024 which means an aspect ratios of 5:4. PVRX2 will probably thinks that the monitor aspect ratio is 4:3 which it is not the case unless it is a CRT! There are no 16:10 CRT's so PVRX2 should always be using square pixels in 16:9 aspect ratio.

[sub]

Thanks, but the figures given even when the are corrected to <AspectRatioMode name="Fill" ratio="0,0.05,1,0.95" /> do not actually solve the problem. What happens is that image is no longer being overscanned properly in the vertical direction like it's supposed to be. Instead the vertical is not ovescanned at all so you see black lines at the top bottom and then scan lines from the top and bottom of the TV image that are not supposed to be displayed on screen and lots of stuff is missing from the horizontal, left and right of the image.

If you're using 0,0.05,1,0.95 then the picture should fill the width of screen, and have black bars at the for the top/bottom 5% of the screen.

If you're talking about garbage that can sometimes be present at the top of the video frame (small white dots), like the VBI info, this is nothing to do with the aspect ratio, and would still be present when the aspect ratio is 100% correct. You can use filters like ffdshow to crop CC/VBI information from the display.

PVRX2 has been programmed to regard monitor aspect ratios incorrectly. The only way to fix PVRX2 is to programme the software to always use square pixels. It assumes that the screen ratio is 16:9 even when the graphic's card resolution is set to 16:10 and therefore concludes that it should use rectangular pixels so displays a 16:10 window instead of a 16:9 window thinking it will be stretched to 16:9 by the monitor. Whoever programmed it does not understand that almost all LCD computer monitors use square pixels and a 16:10 graphics resolution such as 1680x1450 is mapped onto a 16:10 screen. This is clearly a bug.

Bollocks. You're wrong. GB-PVR doesnt make any assumption about the physical pixel shape of your TV, and its current system works fine with square or rectangular pixels. You may have to tweak those values I mentioned for 16:10, but with the correct values plugged in, it'll work just fine.

[stustunz]

you do know to press f7 to try the different aspects to get to the correct one

[Agamemnon]

Sub, you can stick your head in the sand and swear for as long as you like. That will not change the fact that GB-PVR does not handle monitor aspect ratios correctly, because if it were I wouldn't be wasting my time here.

Stustunz I have tried F7. If I set <AspectRatioMode name="LetterBox" ratio="0,0.05,1,0.95" /> it displays the picture correctly. Thanks.

This does not solve the underlying problem though which is that in "Auto" mode the image displayed make's everyone's faces look too narrow because the software is assuming the aspect ratio of my monitor is 16:9 despite the fact that the graphics resolution is set to 1680x1050 which implies a 16:10 aspect ratio for the monitor, which is what it should be, and which is the default ratio for all widescreen monitors even to expensive 1920x1200 variety. Only HD TVs use a 16:9 aspect ratio.

GB-PVR should be assuming square pixels. It isn't. It's displaying a 16:9 window on my monitor when it should be displaying a 16:10 window instead, like Windoes Media Player, or DScaler which has it's different menu tabs to set the correct monitor aspect ratio and the correct source aspect ratio.

Hopefully the developers will read what I have written and fix the problem.

[sub]

Hopefully the developers will read what I have written and fix the problem.

I am the only developer, and I'm 100% sure my logic is able to cope irrespective of what the physical pixel shape is. Trust me, I've spent alot more time thinking about aspect ratios than you have.

As I said above, just tweak the 'Fill' and 'PillarBox' to whatever you'd prefer them to be. The defaults are there are for 16:9, since my lounge plasma is 16:9, but you can easily set them for 16:10.

GB-PVR should be assuming square pixels.

It doesnt need to do that. Infact that would be a bad idea. There is many people using TVs without square pixels.