Non native 4:3 resolution centered on 16:9 screen

Discussion about old graphics cards, monitors and video related things.

Non native 4:3 resolution centered on 16:9 screen

Postby hwh » 2017-5-09 @ 01:10

So, I've been mulling over the shortscreen issue for a while now. It's not good to have letterboxing...and ATM I have a 5:4 screen, which is great on 4:3 letterboxing but does a pretty bad job on 4:3 resolutions like 1024x768. Not a bad screen, not a great screen, get to the point.

If I get a 1366x768 and run something in 1024x768, it should be centered, I suppose. But what I am wondering is will it be sharp? Technically there shouldn't be any "scaling" because the vertical pixels are 1:1 and there are plenty (171) of pixels on the side into which this 1024x768 container might fit. Evenly. But is that how it works? Will a screen vainly try to split this 342 pixel vertical bar somehow to make it blurry?

So, I decided to test this with my 5:4 monitor (1280x1024). I set a resolution of 1024x1024. Well...the screen and driver responded by zooming in on this 1024 width and then giving me areas above and below the screen I can scroll to. :blah: I tried 800x1024. Again, tower shaped blurry picture. I tried it in dosbox and it seemed to work - but I need this to work on any 4:3 software. So the drivers have to be able to do that, if software configured to ask for 1024x768 will just stretch the 1024 across 1366 pixels.

I'm using nvidia drivers on WinXP. So it might be a video card change. Does AMD allow you to toggle scaling? Pretty funny huh, big fancy nvidia doesn't show a basic option like scaling?
hwh
Member
 
Posts: 127
Joined: 2008-7-06 @ 18:18

Re: Non native 4:3 resolution centered on 16:9 screen

Postby PhilsComputerLab » 2017-5-09 @ 01:21

A good 1366 x 768 monitor does the 1:1 pixel mapping on its own. But yes, once setup, it is a perfect 1:1 pixel mapped image.

Nvidia does suck with scaling options under XP, no other words for it. Older drivers sometimes work better. Sometimes when fiddling around with DVI and VGA cables, the scaling menu will magically appear. And yes, ATI / AMD does it better in this regard.
User avatar
PhilsComputerLab
Hardware Mod
 
Posts: 6179
Joined: 2014-9-28 @ 03:33
Location: Western Australia

Re: Non native 4:3 resolution centered on 16:9 screen

Postby Azarien » 2017-5-09 @ 08:21

I have a netbook with 1024x600 screen.

800x600 looks very sharp, 1:1.

PhilsComputerLab wrote:Sometimes when fiddling around with DVI and VGA cables, the scaling menu will magically appear. And yes, ATI / AMD does it better in this regard.

On a HD5770 (and earlier HD4xxx and earlied HD3850) the scaling menu shows up in the settings when I connect my monitor with DVI cable, bot not when I connect the same monitor with VGA cable.
Azarien
Oldbie
 
Posts: 613
Joined: 2015-5-14 @ 07:14

Re: Non native 4:3 resolution centered on 16:9 screen

Postby dr.zeissler » 2017-5-09 @ 10:28

Another thing that REALLY drives me crazy is how to center the screen in text- and gfx-modes on a tft.
Ironically you can find no active discussion on that, I think nearlly all retro-usrs should have this issue.
Only one machine does not have it at all and that is my HPnx6125. On this laptop all resoulutions are
centered, regardingless whot colordepth or resolution is shown.

The matrox g200a has also a relatively good centered image, but all others don't.

How do you deal with that problem? or do you just ignore it?
CPU: PII 133-333 MOBO: SNI-D981 RAM: 512- FDD: Dualfloppy 3,5"HD/5,25"HD - 3,5"HD - 5,25"DD ISA-Catweasel HDD: 2x40GB - DVD
ISA(3): Audician32-S2Dreamblaster - GusACE PCI(3): Monster3D- Intel NW AGP(1): 3dfx V3-3000
dr.zeissler
Oldbie
 
Posts: 1755
Joined: 2011-9-28 @ 15:33

Re: Non native 4:3 resolution centered on 16:9 screen

Postby Azarien » 2017-5-09 @ 11:06

What do you mean by "centered"? Pillar-boxed while preserving original aspect ratio?

Yes, it's often a problem. Sometimes you have the option to fix it in graphics drivers settings, sometimes you don't.
It depends on your graphics drivers, type of monitor connection and the monitor itself.
For example, I have a Samsung 16:10 monitor that can't deal with 4:3 resolutions correctly. It tries to display them centered, but the resulting aspect ratio is wrong, about 5:4 or so.
On the other hand, with DVI connection I can choose "scaling by GPU" in graphics drivers settings, so the monitor always sees its native 1680x1050.
Then 1280x960 looks perfect for gaming with just a little blur.

On two different laptops with Intel integrated graphics running Windows 10 I had to force install original Windows 7 drivers and prevent them from "upgrading".
The original drivers have scaling settings, the ones that come with Windows 10/Windows Update don't.
Azarien
Oldbie
 
Posts: 613
Joined: 2015-5-14 @ 07:14

Re: Non native 4:3 resolution centered on 16:9 screen

Postby dr.zeissler » 2017-5-09 @ 11:15

A TFT normally displays Textmode 80x25 and gfx-mode 320x200 in the same resolution (720x400),
I I center textmode while displaying volkov-commander and start a vga-lowres game, the image
is not centered it has moved to the right, If I center the gfx-mode 320x200 and go back to the volkov
the textmode is not centered any more. Sometimes the same Resolution with the same colordepth AND
frequency is not centered :(

e.g.:
640x480@32Bit@60Hz in Win3.11
640x480@32Bit@60Hz in Win9x

This not centered image drives me crazy on these old machines.

I have searched for some tools in order to change the output of the gfx-card.
But I can't find anything that works the way I wanted to.
I think the people from HP made a very good job to calibrate the 15"TFT of
the notebook to display all resolutions exactly centered.

Doc
CPU: PII 133-333 MOBO: SNI-D981 RAM: 512- FDD: Dualfloppy 3,5"HD/5,25"HD - 3,5"HD - 5,25"DD ISA-Catweasel HDD: 2x40GB - DVD
ISA(3): Audician32-S2Dreamblaster - GusACE PCI(3): Monster3D- Intel NW AGP(1): 3dfx V3-3000
dr.zeissler
Oldbie
 
Posts: 1755
Joined: 2011-9-28 @ 15:33

Re: Non native 4:3 resolution centered on 16:9 screen

Postby Gamecollector » 2017-5-09 @ 11:22

dr.zeissler wrote:A TFT normally displays Textmode 80x25 and gfx-mode 320x200 in the same resolution (720x400)

Many videocards use 640x480 (not 720x400) for startup screens. And only BIOS screens are affected.
By the way - 320x200 and 640x200 must be displayed as 640x400, not 720x400.
The trouble is - there is no easy method to detect the difference between 720x400 and 640x400 VGA signals. So TFTs just converts all 400-lines modes to 720x400.

I have the centering problem on my Sapphire Radeon HD3850 AGP. The fix is - center the BIOS screen with the TFT autoadjust then adjust the 640x480@60 mode in WinXp Catalyst settings (Monitor properties/Adjustments).
Asus P4P800 SE/Pentium4 3.2E/2 Gb DDR400B,
Radeon HD3850 Agp (Sapphire), Catalyst 14.4 (XpProSp3).
Voodoo2 12 MB SLI, Win2k drivers 1.02.00 (XpProSp3).
User avatar
Gamecollector
Oldbie
 
Posts: 1319
Joined: 2010-10-06 @ 22:17

Re: Non native 4:3 resolution centered on 16:9 screen

Postby dr.zeissler » 2017-5-09 @ 16:43

It gets much worse ich a voodoo-card is in the system. win9x with native 2d card at 640x480@60hz is not the same as glide/ogl voodoo at 640x480@60hz.
Currently my multi-boot machine has about 3-4 different screen-adjustments so I have constantly using the "auto" function on my tft to get the screen
centered and fully displayed :(
CPU: PII 133-333 MOBO: SNI-D981 RAM: 512- FDD: Dualfloppy 3,5"HD/5,25"HD - 3,5"HD - 5,25"DD ISA-Catweasel HDD: 2x40GB - DVD
ISA(3): Audician32-S2Dreamblaster - GusACE PCI(3): Monster3D- Intel NW AGP(1): 3dfx V3-3000
dr.zeissler
Oldbie
 
Posts: 1755
Joined: 2011-9-28 @ 15:33

Re: Non native 4:3 resolution centered on 16:9 screen

Postby Gamecollector » 2017-5-09 @ 19:30

Voodoo2 640x480@60 image shifting is the programmers fault. They used correct timings for 640x480@60 but forgot the card specification. Voodoo2 uses +1/+1/+2 shift for hSyncOn/hSyncOff/hBackporch values. So the result is different from the 640x480@60 VGA.
You can change this with SSTV2_HSYNC= and SSTV2_BACKPORCH= variables but the result is global and affects all Voodoo2 resolutions.
Asus P4P800 SE/Pentium4 3.2E/2 Gb DDR400B,
Radeon HD3850 Agp (Sapphire), Catalyst 14.4 (XpProSp3).
Voodoo2 12 MB SLI, Win2k drivers 1.02.00 (XpProSp3).
User avatar
Gamecollector
Oldbie
 
Posts: 1319
Joined: 2010-10-06 @ 22:17

Re: Non native 4:3 resolution centered on 16:9 screen

Postby dr.zeissler » 2017-5-09 @ 19:57

what about voodoo1?
CPU: PII 133-333 MOBO: SNI-D981 RAM: 512- FDD: Dualfloppy 3,5"HD/5,25"HD - 3,5"HD - 5,25"DD ISA-Catweasel HDD: 2x40GB - DVD
ISA(3): Audician32-S2Dreamblaster - GusACE PCI(3): Monster3D- Intel NW AGP(1): 3dfx V3-3000
dr.zeissler
Oldbie
 
Posts: 1755
Joined: 2011-9-28 @ 15:33

Re: Non native 4:3 resolution centered on 16:9 screen

Postby hwh » 2017-5-13 @ 03:33

PhilsComputerLab wrote:A good 1366 x 768 monitor does the 1:1 pixel mapping on its own. But yes, once setup, it is a perfect 1:1 pixel mapped image.

Nvidia does suck with scaling options under XP, no other words for it. Older drivers sometimes work better. Sometimes when fiddling around with DVI and VGA cables, the scaling menu will magically appear. And yes, ATI / AMD does it better in this regard.


That's very helpful; thank you. Are there any ATI cards you recommend...PCI-E, with decent XP drivers?

I might be able to do it with my current graphics card and a DVI cable (which I need to get) but I'm not counting on it.
hwh
Member
 
Posts: 127
Joined: 2008-7-06 @ 18:18

Re: Non native 4:3 resolution centered on 16:9 screen

Postby PhilsComputerLab » 2017-5-13 @ 03:34

Hmm the one I use mostly is a 6770 I believe. Decent performance for Windows XP.
User avatar
PhilsComputerLab
Hardware Mod
 
Posts: 6179
Joined: 2014-9-28 @ 03:33
Location: Western Australia

Re: Non native 4:3 resolution centered on 16:9 screen

Postby dr.zeissler » 2017-9-05 @ 11:22

Laptop screens are perhaps "pre-ajusted" because of the lacking "auto-center" function of the laptop-screen.
Therefore on a laptop the image is centred in plain dos-texmode and low-res gfx-mode like 320x200 with 16 (ega) or 256 (VGA) colors.

I am very interested in a grogram that lets me center the image of the gfx-card to my tft-screen for every resolution and frequency,
because some Games/Demos use 60Hz, some 65Hz or 59Hz or 75 and so one.

I remeber a gfx-card (must be 1995 or before) that had included a programm on the driver-disk that lets you ajust the image on the
screen. The tool must be able to "store" the corrected informations about the image to the "firmware"/"bios" or whatever is possible
to make it durable.

That's what I REALLY need. Any idea?

e.g. my G200/8MB is centered in "norton-commander" and lowres 320x200, while displaying both with 720x400 on my nec l367.
The g400 has the "norton-commander" centered and if I start a lowres game 320x200 the image starts on the left 0,5 centimetres
and the 0,5 centimeters are not visable on the right. If I correct that while pressing "auto" in gfx-mode and go back the textmode
after the game. my "norton-commander" has trhe exact opposite. Right 0,5centimerts black and on the left 0,5cm is not visable.
CPU: PII 133-333 MOBO: SNI-D981 RAM: 512- FDD: Dualfloppy 3,5"HD/5,25"HD - 3,5"HD - 5,25"DD ISA-Catweasel HDD: 2x40GB - DVD
ISA(3): Audician32-S2Dreamblaster - GusACE PCI(3): Monster3D- Intel NW AGP(1): 3dfx V3-3000
dr.zeissler
Oldbie
 
Posts: 1755
Joined: 2011-9-28 @ 15:33

Re: Non native 4:3 resolution centered on 16:9 screen

Postby hwh » 2019-5-04 @ 20:53

Checking in. DVI cable doesn't seem to do much on the random old screen I have. This is a 5:4 1280x1024. The screen just says it's DVI instead of VGA and behaves the same IIRC.

Now, 1024x768 should fit in there just fine, and such programs will letterbox correctly, but unfortunately the result is quite on the blurry side. I also had a look at 1366x768 screens. They are becoming less common now. They come in a few sizes, although I am wondering about image quality. There are some "televisions" that do 1366x768, like 24", but I have a feeling what they offer in size will be more than made up for with degraded image quality.

Haven't bought one cause I'm poor :blah:

I looked at my scaling options for a 1024x768 program, nVidia driver. My choices are

1. NVIDIA scaling - distorts to fill screen, blurry. Surprisingly this is the worst choice!

2. NVIDIA scaling with fixed aspect ratio - The same as NVIDIA scaling but it's in 4:3. Blurry :( This is what I actually use!

3. Display's built in scaling - Here is what's really important. The display distorts to full screen, but it's SHARP. Graphics are a little "not exact" but it looks better than nVidia's own scaling. I just refuse to use the distorted aspect ratio.

4. No scaling - You might think this could be the right choice. Using it generates a tiny (like 800x600 sized) screen in the center, sharp, but unacceptably small. It's odd because the resolution should almost fill the screen, but it does not. Needless to say, the image is sharp and correct, it's just very disappointing. I would hope with a 1366x768 screen, I would get a full height image (not sure how the hell I wouldn't, but this tiny 1024x768 screen on my 1280x1024 panel is implying there is a way).
hwh
Member
 
Posts: 127
Joined: 2008-7-06 @ 18:18

Re: Non native 4:3 resolution centered on 16:9 screen

Postby SPBHM » 2019-5-05 @ 05:43

hwh wrote:
4. No scaling - You might think this could be the right choice. Using it generates a tiny (like 800x600 sized) screen in the center, sharp, but unacceptably small. It's odd because the resolution should almost fill the screen, but it does not. Needless to say, the image is sharp and correct, it's just very disappointing. I would hope with a 1366x768 screen, I would get a full height image (not sure how the hell I wouldn't, but this tiny 1024x768 screen on my 1280x1024 panel is implying there is a way).


your screen is 1280x1024 and you are telling it to just use 800x600 of those pixels, it's going to be much smaller than full res...
this is the best option for image quality by far, but yes, it's small... it's more useful when the resolution you are using is closer to the full panel res, like 1280x960, or maybe 1152x864,
but even 1024x768 on my 19" 1280x1024 screen, was still usable, like a normal 15" screen in size.

the other scaling options, you are creating more pixels based of a 1 pixel source basically, so it depends on what the base and target resolution are, 2x scaling, like 800x600 on a 1600x1200 screen should look clean (2x, integer scaling), while 800x600 on 1280x1024 is harder, but I think in general all scaling gets a blur filter with the driver option, even when it's not needed (like 2x)
SPBHM
Oldbie
 
Posts: 585
Joined: 2012-10-26 @ 15:59

Re: Non native 4:3 resolution centered on 16:9 screen

Postby dr_st » 2019-5-05 @ 06:29

SPBHM wrote:2x scaling, like 800x600 on a 1600x1200 screen should look clean (2x, integer scaling)
Should, but in many cases doesn't, because of subpixel rendering, and stuff like that.
User avatar
dr_st
l33t
 
Posts: 2002
Joined: 2015-4-09 @ 07:18

Re: Non native 4:3 resolution centered on 16:9 screen

Postby hwh » 2019-5-07 @ 05:07

SPBHM wrote:your screen is 1280x1024 and you are telling it to just use 800x600 of those pixels, it's going to be much smaller than full res...


That's not what I said. I selected no scaling for 1024x768 and I got a centered sharp picture about 2/3 of the screen size, letterboxed and pillarboxed. I compared it to the screen area of 800x600 compared to 1280x1024. It's not 800x600.

Which is bullshit because 1024x768 is very similar to 1280x1024 and when it's scaled correctly it fills 95% of the screen with no pillarboxing, only letterboxing. That's fine, that's correct. It's just very blurry. It's just the scaling options on this particular panel and that the options from nVidia are useless with this panel. IN FACT, as I just said in the previous post, when I tell the monitor to do scaling via nVidia's menu (the monitor seemingly has no controls for this) it looks very sharp, but I can't tell the monitor to not distort 1024x768 into 5:4. Otherwise that would be awesome, and logical. There are panels that will do it correctly, this just isn't one of them and I figured at least I would have a greater chance of a better result if there were no "scaling" since 1024x768 doesn't have to be "scaled" on a 1366x768 panel.

If I were allowed, I would, like a CRT, adjust the screen size to fit without scaling, but the controls are disabled in the OSD, IIRC VGA or DVI.
hwh
Member
 
Posts: 127
Joined: 2008-7-06 @ 18:18

Re: Non native 4:3 resolution centered on 16:9 screen

Postby dr_st » 2019-5-07 @ 05:48

I'm still not sure what problem you are complaining about.

With 1:1 scaling, 1024x768 on a 1280x1024 screen is going to take 80% of the screen horizontally, and 75% vertically, so 60% of the total screen area. That's the only way you're going to get a sharp image in a non-native resolution on an LCD.
User avatar
dr_st
l33t
 
Posts: 2002
Joined: 2015-4-09 @ 07:18

Re: Non native 4:3 resolution centered on 16:9 screen

Postby SPBHM » 2019-5-12 @ 17:46

dr_st wrote:
SPBHM wrote:2x scaling, like 800x600 on a 1600x1200 screen should look clean (2x, integer scaling)
Should, but in many cases doesn't, because of subpixel rendering, and stuff like that.


have you tried the doublescan options that some nvidia drivers had for the VGA output?
it was made for CRTs to avoid scanlines at 640x480 doubling it to 1280x960, but I found that it worked well on my 1280x1024 LCD, I also enabled the fixed aspect ratio timing,
it's not perfect, because by default it will cut a bit of picture from both sides of the image (while adding the letterbox to top and bottom), but if I use the display's auto settings, and after that change the "clock" option down on the menu to 11 it actually shows the entire 640x480 picture (with a single black bar on the bottom for aspect ratio correction) and it's really sharp, like no filtering it's a huge improvement over any other method for 640x480 on this monitor...
ah yes, the card is actually still sending a 1280x1024 output, it's just that with the regular 640x480 GPU scaling it becomes a blurry mess with filtering, but this double scan thing works great.... I would think the same is possible with 800x600 on a 1200 screen.... it's just that I really don't know which cards and what drivers support it (I'm using XP with 93.71 with a Geforce FX via VGA)... but it's frustrating that something like this is not more easily accessible... I've looked at an 8400GS with the latest drivers and it doesn't offer the option.
SPBHM
Oldbie
 
Posts: 585
Joined: 2012-10-26 @ 15:59

Re: Non native 4:3 resolution centered on 16:9 screen

Postby dr_st » 2019-5-12 @ 19:13

Well, I don't generally run LCDs on VGA, but I guess if I ever do, and I have a system that has an nVidia card, which has with this option in the driver, I can give it a shot. That's a lot of "if"s. :)
User avatar
dr_st
l33t
 
Posts: 2002
Joined: 2015-4-09 @ 07:18


Return to Video

Who is online

Users browsing this forum: bregolin, dionb, the3dfxdude and 2 guests