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VGA Capture Thread

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Reply 1001 of 1046, by Kordanor

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So I ordered the 4k Capture thing from Elgato, because I need to use it for a camera anyways.
However I was wondering...there is nothing to install (well, it got its software but that seems to be standalone, but no drivers or anything), with the camera it becomes a bit hard to test colors and I thought the most easiest way to test it, would be to just have a virtual monitor in the same PC.

So I recorded One video via OBS on my normal monitor (display port) having a black screen. And then I recorded another one on my "elgato Monitor", meaning the HDMI cable went directly into the elgato 4k thing.
Then I opened both videos and put together a picture. That way everything went through the same phases and compressions (up to picture compression at the end) but you can see a very clear difference:

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The right side, which is the normal screen is far blacker than the Elgato side (left).

Now I am wondering, is that because
1. A hdmi cable issue? Very unlikely, I also tested 2 different cables
2. Elgato just cant capture real blacks?
3. Some configuration for Elgato required?
4. Some issue with the HDMI signal?

Regarding the HDMI signal: I am aware that there is an option (normally) to switch to full color range.
However:

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So....any other ideas here? I know it's not 100% related to VGA at this point, but If there is already such a loss with the elgato cam in itself, then it can only get worse if you add additional devices.

Reply 1002 of 1046, by darry

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Kordanor wrote on 2020-12-10, 21:56:
So I ordered the 4k Capture thing from Elgato, because I need to use it for a camera anyways. However I was wondering...there is […]
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So I ordered the 4k Capture thing from Elgato, because I need to use it for a camera anyways.
However I was wondering...there is nothing to install (well, it got its software but that seems to be standalone, but no drivers or anything), with the camera it becomes a bit hard to test colors and I thought the most easiest way to test it, would be to just have a virtual monitor in the same PC.

So I recorded One video via OBS on my normal monitor (display port) having a black screen. And then I recorded another one on my "elgato Monitor", meaning the HDMI cable went directly into the elgato 4k thing.
Then I opened both videos and put together a picture. That way everything went through the same phases and compressions (up to picture compression at the end) but you can see a very clear difference:
Elgato.PNG

The right side, which is the normal screen is far blacker than the Elgato side (left).

Now I am wondering, is that because
1. A hdmi cable issue? Very unlikely, I also tested 2 different cables
2. Elgato just cant capture real blacks?
3. Some configuration for Elgato required?
4. Some issue with the HDMI signal?

Regarding the HDMI signal: I am aware that there is an option (normally) to switch to full color range.
However:
Elgato2.PNG

So....any other ideas here? I know it's not 100% related to VGA at this point, but If there is already such a loss with the elgato cam in itself, then it can only get worse if you add additional devices.

IMHO, it looks like your source is outputting limited range RGB, whereas your capture application (OBS) is expecting full range RGB .

I do not have this issue on my side, as I am able to send full range RGB to my Camlink 4K .

For testing, I used a Laptop with an Nvidia Quadro that was hooked to an Elgato Camlink 4K via HDMI . I was able to choose full range RGB as an output option .

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I then used Virtualdub2 to capture at 1920x1080 in YUY2 and compress losslessly

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to x264

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and saved the following stills from MPC-HC :

White point :

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Black point :

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I suggest you consider updating you CamLink 4K firmware to the latest version : https://help.elgato.com/hc/en-us/articles/360 … Gaming-hardware
Disclaimer : I am not responsible if something goes wrong .

I do not use OBS, so I cannot really help you with that, but, as an alternative to send full range RGB from the video card, you can set OBS to process incoming video as limited range (which is likely what your video card is outputting), which should fix the black level and white level .
See this example for another Elgato product (should be identical to the Camlink 4K) .
https://obsproject.com/forum/resources/gettin … obs-studio.617/

Reply 1003 of 1046, by Kordanor

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Yeah, actually found this post right after writing here and posted there as well, as the options there seem to be outdated - or its just because of another device, but I doubt that.
Will check the firmware stuff.

Also thanks a lot for checking on your PC!

Reply 1004 of 1046, by CaelThunderwing

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since im going to be replacing a Display of mine that Had VGA and what i will have doesnt, whats a decent but not bank breaking means of Converting VGA to HDMI that supports a good range of Resolutions?

Reply 1005 of 1046, by darry

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CaelThunderwing wrote on 2020-12-12, 00:51:

since im going to be replacing a Display of mine that Had VGA and what i will have doesnt, whats a decent but not bank breaking means of Converting VGA to HDMI that supports a good range of Resolutions?

Define "bank breaking" and define "decent" .

Also,
Do you want 70Hz in-out capability for DOS games or is 70-in and 60Hz OK or do you need 70Hz at all ?
Do you intend to use the display in 4:3 mode and, if so, at what resolutions ?

Reply 1006 of 1046, by CaelThunderwing

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darry wrote on 2020-12-12, 01:25:
Define "bank breaking" and define "decent" . […]
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CaelThunderwing wrote on 2020-12-12, 00:51:

since im going to be replacing a Display of mine that Had VGA and what i will have doesnt, whats a decent but not bank breaking means of Converting VGA to HDMI that supports a good range of Resolutions?

Define "bank breaking" and define "decent" .

Also,
Do you want 70Hz in-out capability for DOS games or is 70-in and 60Hz OK or do you need 70Hz at all ?
Do you intend to use the display in 4:3 mode and, if so, at what resolutions ?

i havent run too many dos game on the one machine, but i've had a few oddball 640x480 full screen games w/ the one adapter i have just not like it and Display nothing. (like Gearhead garage does this,), i know i cant use the Startech USBCAP3 capture device (Blacklisted USB3 controller[ASMedia]) and i want to stay within 150$ n under if possible. 90% of my games im pretty sure run in 60hz displaymodes.

i have something like this https://www.amazon.com/Cable-Matters-Converte … tronics&sr=1-46 (i doubt even the exact one i have supported 640x480)

Reply 1007 of 1046, by darry

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CaelThunderwing wrote on 2020-12-12, 01:34:
darry wrote on 2020-12-12, 01:25:
Define "bank breaking" and define "decent" . […]
Show full quote
CaelThunderwing wrote on 2020-12-12, 00:51:

since im going to be replacing a Display of mine that Had VGA and what i will have doesnt, whats a decent but not bank breaking means of Converting VGA to HDMI that supports a good range of Resolutions?

Define "bank breaking" and define "decent" .

Also,
Do you want 70Hz in-out capability for DOS games or is 70-in and 60Hz OK or do you need 70Hz at all ?
Do you intend to use the display in 4:3 mode and, if so, at what resolutions ?

i havent run too many dos game on the one machine, but i've had a few oddball 640x480 full screen games w/ the one adapter i have just not like it and Display nothing. (like Gearhead garage does this,), i know i cant use the Startech USBCAP3 capture device (Blacklisted USB3 controller[ASMedia]) and i want to stay within 150$ n under if possible. 90% of my games im pretty sure run in 60hz displaymodes.

i have something like this https://www.amazon.com/Cable-Matters-Converte … tronics&sr=1-46 (i doubt even the exact one i have supported 640x480)

a) According to the manual, https://www.cablematters.com/images/Product/f … er%20Manual.pdf , 720x400 and 640x400 ( line-doubled 320x200 ) are not officially supported (may still work).
b) According to one Amazon comment, this adapter, BIOS screen is not visible, which points to a) being accurate
c) According to one Amazon comment, this adapter has 1 second worth of latency (the answer to the comment makes it unclear if this actually the case) .
d) It is unclear exactly how 4:3 input is converted to 16:9 1920x1080 that this thing apparently scales to . One Amazon comment says there was "no distortion", whether that means pillarbox 4:3 with black bars on each side or some kind of non linear horizontal stretching to minimize the appearance of distortion while giving a 16:9 full screen picture is anybody's guess .

Having tested multiple VGA to DVI/HDMI converters and scalers, if you don't need 70Hz output (70Hz input works but is converted to 60Hz, so BIOS and VGA DOS games work), my vote for relatively inexpensive and no hassle goes to the Extron RGB-300 DVI (or its HDMI variant) . It can usually be bought used for less than 100 $US (sometimes much less), works with pretty much anything except extremely oddball resolutions (like some demo compo stuff that plays with the VGA CRTC) . Latency is apparently not bad for this (AFAICR from a shmups post) and scaling is configurable to taste . Additionally, it will work well with 16:9 monitors that have limited aspect ratio controls and allow 4:3 content to be displayed at the proper aspect ratio .

If you want something better, there is the OSSC . It is more expensive and requires a monitor capable of handling the VGA resolutions and refresh rates that you want to use directly (not scaled) or line-doubled . Additionally, the monitor you use with must be able to display the 4:3 resolutions you want to use as 4:3 to maintain proper aspect ratio . This is usually not an issue for most square pixel 4:3 resolutions (640x480 , 800x600 , 1024x768 , etc) . This is because the OSSC is not a scaler .The advantages are virtually zero input lag, a sharper image (if using line-doubling) and 70Hz in/out capability .

Reply 1008 of 1046, by bumpnthump05

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So, Ive got a question for everyone. I restore and rebuild old arcade game cabinets for my own collection, and in the past i have used a converter board that takes CGA/EGA/VGA signals from arcade boards and converts them to VGA so people can LCD convert an arcade game. (Shudders) I was thinking i wonder if they make one that converts the same video signals to HDMI. Well come to find out, they do. It accepts VGA, as well as the raw wire inputs from an arcade cabinet. Arcade games have ALWAYS had funny resolutions, and funny refresh rates, so they do a pretty good gamut of resolutions and refresh rates. They cost $39 w/o the power adapter or $45.98 with the power adapter.

https://www.arcaderenovations.com/arcade-cga- … rter-board.html

I was wondering if anyone has tried to use one of these, or if some of the pros can look into these to see if its a possible low cost HDMI converter. I worked in the past previously with the converter that takes the same signals and converts them to VGA. The converter has tons of video adjustments in the menu to center the image, zoom, and such. I've been looking for a under $60-70 QUALITY option to capture VGA from my retro computer setups (on a KVM switch) so i can stream them on Twitch. My computer is running windows 95, and i plan on gaming in DOS as well as windows at 640x480 or 800x600.

It appears a guy has done a similar thing with his old Tatung Einstein that outputs 56 × 192, 16 colours https://www.youtube.com/watch?v=iWjPNdxeFBA

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Reply 1009 of 1046, by maxtherabbit

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it's just a bog standard GBS-8200 with a ADC grafted on to it

ironically the Tvia 5725 scaler IC supports native digital RGB output, but this design doesn't use it.

Reply 1010 of 1046, by kolderman

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bumpnthump05 wrote on 2020-12-13, 07:19:

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Are those Creative speakers placed sideways under the monitors? Are they designed that way?

Reply 1011 of 1046, by bumpnthump05

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kolderman wrote on 2020-12-13, 19:49:
bumpnthump05 wrote on 2020-12-13, 07:19:

arcade-cga-ega-vga-rgb-to-hdmi-video-converter-board-connection-diagram (1).jpg
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Are those Creative speakers placed sideways under the monitors? Are they designed that way?

Not designed that way, but the bases of the speakers are removable with a single phillips screw, so i took them off and laid the speakers sideways. Sound perfect and dont vibrate.

Reply 1012 of 1046, by bumpnthump05

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Well, I ended up going and getting a 2nd hand used Datapath VisionRGB-E1S off of eBay. I purchased a powered VGA splitter, and a C2G shielded VGA cable with Audio. It should all be here by Saturday. Now i will be able to capture any of the PC's on my KVM switch with good quality. But im really intrigued of IMI's video he posted on the previous page.

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imi wrote on 2020-11-20, 19:55:

here's how that sometimes looks:
https://www.youtube.com/watch?v=ua1wAYgZNbk

This question is more aimed at IMI, but how did you manage to create a CRT bezel overlay like that with reflective properties around the edge of the CRT bezel? I have only seen that done before through retroarch. Is what you're using to generate the bezel reflections playing your capture through the ffmpeg core and then grabbing the output of retroarch for your OBS?

Reply 1013 of 1046, by Kordanor

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imi wrote on 2020-11-20, 19:55:

here's how that sometimes looks:
https://www.youtube.com/watch?v=ua1wAYgZNbk

This question is more aimed at IMI, but how did you manage to create a CRT bezel overlay like that with reflective properties around the edge of the CRT bezel? I have only seen that done before through retroarch. Is what you're using to generate the bezel reflections playing your capture through the ffmpeg core and then grabbing the output of retroarch for your OBS?

I'll join in there. Didnt realize that before.
Maybe some filters in OBS?
That said, what program do you (IMI but also others) use in the end to "save" the actual video to your harddrive? OBS and then potentially process it again to make it smaller? Or do you use different programs altogether?

Reply 1014 of 1046, by adalbert

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I don't know how the overlay in IMI's video was done, but I just wanted to challenge myself and tried to do something like that with OBS + StreamFX addons (https://obsproject.com/forum/resources/stream … obs-studio.578/)

I mainly used mirrored copies of video capture scene and added box blur filter (streamfx)

It's not as good but maybe you can tune it to your needs 😁
BTW replace that TV image with your own, as I have no idea about the exact copyrights here 😜

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Reply 1015 of 1046, by imi

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bumpnthump05 wrote on 2020-12-15, 16:28:

This question is more aimed at IMI, but how did you manage to create a CRT bezel overlay like that with reflective properties around the edge of the CRT bezel? I have only seen that done before through retroarch. Is what you're using to generate the bezel reflections playing your capture through the ffmpeg core and then grabbing the output of retroarch for your OBS?

I created that mainly directly within OBS via a whole array of filters and shaders and custom alpha masks, was quite a bit of work to get it just right ^^
basically I'm creating the reflections manually from mirroring the captured image, so yeah, very similar to the above ^^
for the curvature and scanlines I used the preexisting shaders from StreamFX and slightly modified them to fit my image better, on the chat monitor there's also 3D transform involved.

I wish I was fluent enough in shaders to create it all as one shader, that would probably be a lot less taxing on hardware too.

Reply 1016 of 1046, by lukas12p

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Hi

What do You recommend for DOS games capture, that support text mode 720x400@70Hz for less than $50?
I have bought these Chinese grabber, but it doesn't support more than 60 Hz

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Reply 1017 of 1046, by darry

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lukas12p wrote on 2020-12-19, 11:53:

Hi

What do You recommend for DOS games capture, that support text mode 720x400@70Hz for less than $50?
I have bought these Chinese grabber, but it doesn't support more than 60 Hz

Look for a good deal on a Datapath E1S . Usually they are about 100$ or less on used market. They are PCI Express. A passive VGA /DVI adapter (the kind they used to bundle with DVI video cards) will be required and is dirt cheap.

The cheapest E1S that I currently see is 65$ .

I doubt that you will find much to choose from for less than 50$ .

Reply 1018 of 1046, by bumpnthump05

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darry wrote on 2020-12-20, 23:45:
Look for a good deal on a Datapath E1S . Usually they are about 100$ or less on used market. They are PCI Express. A passive VGA […]
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lukas12p wrote on 2020-12-19, 11:53:

Hi

What do You recommend for DOS games capture, that support text mode 720x400@70Hz for less than $50?
I have bought these Chinese grabber, but it doesn't support more than 60 Hz

Look for a good deal on a Datapath E1S . Usually they are about 100$ or less on used market. They are PCI Express. A passive VGA /DVI adapter (the kind they used to bundle with DVI video cards) will be required and is dirt cheap.

The cheapest E1S that I currently see is 65$ .

I doubt that you will find much to choose from for less than 50$ .

I can second this. After tons of looking, hours of research with no clear answer, i decided to purchase a used Datapath E1S off of ebay for like $80. Its supposed to be delivered today or tomorrow i believe. Not only can it capture VGA, but also almost every video format up to 1080P through a DVI to HDMI adapter. You can even purchase a SCART2DVI board which takes video & audio inputs from retro game consoles via a SCART cable, and lets you capture RGB video from actual game consoles. Even has a 3.5mm audio passthrough to hook into the audio input of your soundcard to capture game audio. scart2dvi2_1200x1200.jpg?v=1561990868