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Experiments in Aspect Ratios

H

hunterjwizzard

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I'm documenting my progress here developing a method to get a 4:3 picture on a 16:9 screen, for the one other person out there who want's to this to.

I tried doing it in software with no luck. Here is my first attempt in hardware:



Using an Extron DVS 304. Unfortunately the quality is not great. A little fuzzy, and as you can see I couldn't get the image to cover the whole screen.

Hot plugging screens does not work great, so I put a 1x4 VGA splitter into the mix. This let's me try different converters while keeping the main screen running.

Let's try again with the Extron RGB-DVI 300:



It certainly looks nice. Image is just a bit fuzzy, but as you can see I'm able to modify the upper display to get a 4:3 image. But there's is a problem:



Doesn't work so good when you launch a 640x480 game. If a game DOES support 1024x768:



Things work ok. Unfortunately most games from the 4:3 era tend to have menus at different resolutions. So the challenge remains. Probably there is a better device for converting the signal.
 
Are you able to make 4:3 640x480 work on the RGB-DVI 300 if you adjust the size/position? If so, you should be possible to save input presets for each resolution so it can handle mode switches without adjustment. But you need to use the serial interface.
 
Plasma said:
Are you able to make 4:3 640x480 work on the RGB-DVI 300 if you adjust the size/position? If so, you should be possible to save input presets for each resolution so it can handle mode switches without adjustment. But you need to use the serial interface.
Click to expand...

I can probably make it work at any resolution, the challenge is as you observed switching resolutions. I've had no luck at all controlling Extron devices remotely(I own 6-7 of them, including a "head" controller unit). The problem is without access to Extron's control software or the ability to write software yourself, you're never going to control these things via serial. Its not like a router where there's a serial CLI, you have to A) know the commands that need to be sent and B)write your own software from scratch in order to send them.

Its been a very frustrating experience, hence why I'd rather find a catch-all solution intelligent enough to detect and incoming signal and spit one out at the corresponding aspect ratio.
 
Third attempt using a video capture device:

YX1I9Ej.jpg


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...I'm actually a little bit annoyed about how effective this one is. I am using a "ClearClick HD Capture Box Platinum", a stand-alone video capture box I usually use for converting VHS tapes to digital. It can flawlessly upscale a VHS signal to 1080P and letterbox it automagically. And it happens to have VGA in. So I plugged the test PC in and what do you know.

The screen blinks out for a few seconds whenever there is a resolution-change, but other than that it just flawlessly displays whatever I want. Same box even does HDMI, so I could use this on my later-era win98 machines.

The downside to all this is... well... this device wasn't designed to do this. Its a video capture system. I would like to find a device that's actually designed for this function. Also mine happens to me mounted inside a custom-built project box that makes it less than ideal(I had to stretch cables across the room to do this test). I won't go into detail about all the reasons why this is a less than ideal long-term solution, except to say that I might do whatever it takes to use it as one in the meantime to I can play some 4:3 games.
 
Attempt #4. Still using the ClearClick HD Capture Box Platinum. Now we're moving away from the experimental setup and into my actual use-case: displaying the 4:3 signal on my 43" main monitor:

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cc0yXui.jpg


I'm not gonna lie. This is exactly what I was trying to achieve. I haven't actually played any of these games yet but I'm working on it. I just feel weird using this device for something I don't feel like it was built to do.
 
hunterjwizzard said:
I can probably make it work at any resolution, the challenge is as you observed switching resolutions. I've had no luck at all controlling Extron devices remotely(I own 6-7 of them, including a "head" controller unit). The problem is without access to Extron's control software or the ability to write software yourself, you're never going to control these things via serial. Its not like a router where there's a serial CLI, you have to A) know the commands that need to be sent and B)write your own software from scratch in order to send them.

Its been a very frustrating experience, hence why I'd rather find a catch-all solution intelligent enough to detect and incoming signal and spit one out at the corresponding aspect ratio.
Click to expand...

Not sure what you mean? Extron SIS is effectively a CLI and all the commands are in the manual. You don't need any special software, just a serial terminal.
 
I want to swear that at least some of my 16x9 monitors have an OSD menu option to not stretch 4x3 video modes, is this a false memory or just a thing they don’t do anymore? I know my 2013 TV can do it.
 
Plasma said:
Not sure what you mean? Extron SIS is effectively a CLI and all the commands are in the manual. You don't need any special software, just a serial terminal.
Click to expand...

That may be the case for NEW Extron devices made in the past 10 years or so, but these things I'm experimenting with are quite a bit older. I've been able to establish serial connections to a few of them but there is no CLI.

Eudimorphodon said:
I want to swear that at least some of my 16x9 monitors have an OSD menu option to not stretch 4x3 video modes, is this a false memory or just a thing they don’t do anymore? I know my 2013 TV can do it.
Click to expand...

I've definitely seen 4:3 signals displayed properly, I know that's a must-have for the custom arcade cabinet set.

The only problem is MY specific main monitor does not have that, and the end-goal here is the ability to play 4:3 games from the comfort of my own desk. If it was just about seeing a proper 4:3 signal I have a 21" CRT where the picture looks better. My problem is I've got a touch of the attention deficit disorder and can no longer sit and play a single game for hours on end the way I once could. My desk has 7 monitors, allowing me to multi-task to my heart's content.
 
CoXhXrr.jpg


Now we're in full "production mode".

This system is different from either of the ones I tested with. It is a VGA-only Voodoo3 graphics card that looks a little fuzzy when upscaled(a problem the newer DVI GeForce card did not have). But it may be as good as it gets.

Another "nifty" feature: the capture device has a line-in that embeds audio in the DVI stream. So despite not being built for it this is a lovely one-stop-shop for converting a VGA signal over to digital while also upscaling the video and preserving the 4:3 aspect ratio. I'm still on the lookout for something better, but in case anyone finds this thread and is having a similar use-case, this device retails for about $150.
 
I wasn't happy with the digitization function on the ClearClick HD Capture Box Platinum, but it does handle the 4:3 conversion better than anything else. I've spent the last few weeks off and on experimenting with the various digitizers in my collection. The clearest picture comes from this chincy little VGA to HDMI dongle made by Mokin. Unfortunately it has no model number and I cannot find it for sale again.

Obviously most people won't have this specific use-case. But someday someone else might stumble across this thread and find something useful.
 
Good to hear you've got good output!
For any others some info on my setup.
I use a Datapath VisionPro for this (common in the retro gaming streaming/YT) and there is a lot of info about this. If you've not seen the RetroRGB website and videos, plenty of info. Essentially DOS and VGA is 'difficult' because most TV/Capture expect 50/60Hz and DOS is 70hz for lower res mode and also pixel doubling so you want to down scale back to 320x200 to reduce noise.
So the pipe is something like capture 720x400 -> decimate to 320x200 -> area scale to 320x240 (aspect correction) -> integer scale to say 1440x960. Some fiddling with phase may be required but the results can be amazing.
 
From a recent programming stream, this is a VGA cable capture from a 286 (its Norton Editor is 80x50 text moode). Text requires slightly different settings from VGA 320x200.

1702101204296.png
 
I am definitely in the market for a better solution. I went through a lot of trouble to set up a whole second desk only to never use it, which got me started on this project. I had not heard of these Datapath VisionPro cards just yet. I'll be getting more into DOS in the coming years, right now my obsession is the win98 era.

I did a bit of digging, these cards seem to be somewhat expensive?
 
There are new but the are usually available 2nd hand on Ebay for a lot less. I got a E2S (2 DVI inputs) for £50+P&P last month and a E1S (1 input) for a little more. Worth searching for Datapath E1S or E2S or Datapath DGC150C (board name of E2S) or DGC133C (1S).
Its basically pro gear from a few years ago, no 4K like there current stuff has but for retro perfect :D
 
No 4k needed.

These cards appear to be DVI capture; what are you using for the initial analog-to-digital?
 
They are technically DVI-I ports, so have the digital and analog pins connected. (they also support component via DVI which I've not tried yet). Any passive VGA to DVI dongle works. The four pins near the bar in DVI is for analog.
No Audio though, so have to bring that via sound card.
1602935519_dvi-vidy.jpeg
 
I use a program called VCS, made explicitly for capturing retro machine with Datapath cards. The author no longer updates the windows version but the last version works fine for me. You can also use Datapath own program that comes with the drivers

Linux: https://github.com/leikareipa/vcs
Windows: The older 'here' link http://r3.fyi/Datapath/MiscKnowledge
Lots of other info on using it at the second link also lots of info on VOGONS

I was using it under Linux, but lots of the streaming software is Windows only, and the old VCS works fine so for now using Windows 11.

I then use OBS or Streamlabs OBS to do a Window Capture of VCS which I then full screen project. The Datapath drivers do support V4L or DirectShow so in theory any software with a video capture api will work but I find that buggy (OBS on Win11 bluescreens if I change any options via DirectShow), so I prefer to use window capture and let VCS or Datapaths own program handle it.

One thing to watch for is the card is a PCI-E x4 connector, not x1 as most non video cards use. So check your capture machine has a spare x4 or greater slot (a x16 slot is fine)
 
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I'm not concerned with capture. All I ever wanted was to play in 4:3 on my big screen, and to have crystal clear picture. I happen to be using a capture device because it modifies the signal properly.
 
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