Artex wrote on 2021-03-18, 18:51:

Now my issue is that I need to deal with the audio piece. I was under the assumption that the second 3.5mm jack on the OSSC could be assigned/linked to any of the input connections. VGA/DSub is RGBHV / AV3 (or button 3 on the remote) but there is no audio out jack for this particular input - it's all HDMI. The output jack can be used as an input for AV2/Component sources or as an output only for AVI1/SCART sources.

So now do I need another box to convert HDMI (Digitized VGA + Audio) to DVI + 3.5mm audio which then would go into my motherboard's line-in for audio capture along with the video from the VisionRGB card?

why not just feed the audio into the PC line-in directly?
no point to go through the OSSC if you don't want to output audio via hdmi.

imi wrote on 2021-03-18, 19:02:

Artex wrote on 2021-03-18, 18:51:

Now my issue is that I need to deal with the audio piece. I was under the assumption that the second 3.5mm jack on the OSSC could be assigned/linked to any of the input connections. VGA/DSub is RGBHV / AV3 (or button 3 on the remote) but there is no audio out jack for this particular input - it's all HDMI. The output jack can be used as an input for AV2/Component sources or as an output only for AVI1/SCART sources.

So now do I need another box to convert HDMI (Digitized VGA + Audio) to DVI + 3.5mm audio which then would go into my motherboard's line-in for audio capture along with the video from the VisionRGB card?

why not just feed the audio into the PC line-in directly?
no point to go through the OSSC if you don't want to output audio via hdmi.

Wow - I'm an idiot. Sorry... Apparently I like over-complicating things. 😀

Are there any decent guides out there for OSSC advanced timing tweaks for DB15/RGBHV?

Artex wrote on 2021-03-23, 00:41:

Are there any decent guides out there for OSSC advanced timing tweaks for DB15/RGBHV?

No but video timings for PC graphics modes are pretty standardized. Look up modelines. The default sampling profiles for 640x480, 800x600, 1024x768 are all bang on out of the box. Both the 400p sampler modes are good to go as well, you just have to manually select the correct one. 720x400 is VGA text mode, 640x400 is low res graphics.

maxtherabbit wrote on 2021-03-23, 03:13:

Artex wrote on 2021-03-23, 00:41:

Are there any decent guides out there for OSSC advanced timing tweaks for DB15/RGBHV?

No but video timings for PC graphics modes are pretty standardized. Look up modelines. The default sampling profiles for 640x480, 800x600, 1024x768 are all bang on out of the box. Both the 400p sampler modes are good to go as well, you just have to manually select the correct one. 720x400 is VGA text mode, 640x400 is low res graphics.

You will need to adjust phase manually, however .

darry wrote on 2021-03-23, 04:29:

You will need to adjust phase manually, however .

Thanks! So this is the type of comment that sparks my interest - is there a good article you've found that goes over what phase is or why it needs adjustment?

because analog RGB is... well analog, there is no specific assignment of "this is pixel X/Y" adjusting to the lines is more trivial than getting each pixel in it's correct position on a line, my crude understanding is phase brings the signal in line with pixels displayed, if they are out of phase things become jittery or soft because the information in the analog signal gets shifted between pixels.

It becomes much easier if you're able to display an image that alternates black and white pixels. Doing so will allow you to much more easily find the correct phase and other adjustments. The phase on everything is different, even if it's coming from the same piece of hardware (two identical video cards will probably have a different phase).

This video can show you what you're looking for and how to dial it in correctly. https://www.youtube.com/watch?v=EBStHr4XCTg

Nice! Thanks all! I'll do some more digging.

Just to update the thread with another success story, I picked up a Magewell Pro Capture HDMI (PCIe 2.0 1x):

https://www.magewell.com/tech-specs/pro-capture-hdmi

I'm feeding it the output of an OSSC and the testing so far (Sharp X68000, PS3, PS4) has shown some fairly impressive capture results. I've not fed it the output of any of my VGA-outputting computers - but they all go via the OSSC anyway.

FYI, this is in Linux, and the Magewell driver SDK seems to be a fairly tiny thing and easy to compile - not like the Blackmagic Design behemoth - and it integrates nicely into OBS as a V4L source.

I just remind my capture devices online sheet if someone want to add some more info, as ask me for rights:
https://docs.google.com/spreadsheets/d/1_15jB … dit?usp=sharing

the latest Windows10 version seems to have broken compatibility with my Startech PEXHDCAP60L unfortunately, as I said previously I can only use driver version 143 or below as anything newer won't give me any picture even though it says there is a signal in the video control panel, but now I get sporadic bluescreens whenever I try to use the capture card 🙁 can get quite annoying.

so I had to do a makeshift solution for now, took out an Extron RGB-HDMI 300A and use a HDMI capture card instead... played around for hours with the settings until I got a result I'm happy with, but it's surprisingly good now, unfortunately it's not as fun to play through the capture window like this as this introduced double latency from the capture card and the scaler, with the PEXHDCAP60L there was barely any latency noticable, so I could even play fast paced games directly from the capture on my main PC.

I thought I'd share anyways what results you can get from the Extron if you spend enough time tinkering with the settings... I set the scaled output to an integer multiple of 320x200 (1440x1000) and adjusted the input signal so the pixels would align as best as possible, then I downsampled the resulting picture in OBS into 320x200 to get rid of any filtering artefacts and scaled it back up to 4:3... I have to readjust it sometimes to make the pixels line up perfectly again but the results are quite good.

the Extron has the advantage at least that it doesn't freak out on changing resolutions like my capture card ^^ but then again, my current setup only works well for 320x200, I'll have to do custom setups for other resolutions in the future, but you can conveniently save presets on the scaler itself.

Has anyone tried any of these three?

https://www.amazon.co.uk/TRIPP-LITE-Audio-Con … 18074092&sr=8-6

https://www.amazon.co.uk/Just-Buy-Converter-A … 8074092&sr=8-12

https://www.amazon.co.uk/DAUERHAFT-Converter- … 33&sr=8-51&th=1

None list refresh rates other than 60, if at all. None list resolutions such as 720*400, if any at all.

I want to capture some DOS gaming. I bought an Elgato HDMI capture card today after being burned on a couple of no-name cards. I am planning on doing Windows 98 capture straight from DVI to Elgato HDMI (assuming the card can do 1024*768 - if not I'll VGA and scale to that res, output 720p or whatever).

Doing a few captures of Dreamcast games at the moment, using my Magewell Pro Capture HDMI card to try and get the hang of the various settings.

This is on Linux, using OBS, and I'm capturing at 1280x960@6FPS0, so it's precisely twice the vertical resolution of the Dreamcast with its 720x480 60Hz (but 640x480 in reality) display.

I initially started out capturing at native resolution; 640x480@60FPS... and those captures looked fantastic on my PC - however Youtube doesn't seem to think anything under 720 vertical lines is worthy of a decent encoding, nor 60fps, so it ends up with a horrid transcoding as shown here:

https://www.youtube.com/watch?v=ZMhdB-vXMGc&t=2s

After uploading line-doubled versions, you can see the difference:

https://www.youtube.com/watch?v=qEYiLLugkYw&t=11s

Encoding is using nvenc using the high quality preset on my 1050Ti. I'm really pleased with both the performance and quality of the Magewell card and with the available resolutions, frame rates and colour spaces that it supports.

After reading this thread, I bought a used Datapath VisionRGB E1S on Ebay for $90 (the same seller had the non-S version for $65 if anyone's interested). I'm a convert. For *years* I struggled with how to capture DOS and VGA output on old hardware, reading tons of stuff and watching YouTube videos of people using four or five devices (splitters, scalers, converters, then usually HDMI capture) just to do this one job, and the answer is just the E1S. It's a fantastic card and it just works, with every resolution I've thrown at it. Zero latency (that I notice), so I can play games while capturing them without a splitter too, just using the input on my modern PC as a monitor. I was a little afraid of the fact that I don't technically have the "required" number of PCIe lanes in my PC - I have three free, and it supposedly requires four - but I guess that's only for if you're actually trying to use multiple simultaneous capture streams. I only need one, and the card happily works with fewer lanes than it says are required if you're not actually using the full bandwidth it's capable of.

I haven't yet quite gotten a workflow that ends up in pristine quality - there's an extra generation of scaling and quality loss that I'm trying to figure out how not to do - but I probably just need to read through more of this thread. I can see that the input direct from the card is beautiful. I'm using OBS, which lets me capture audio and video at the same time, and then I import those clips into Davinci Resolve for editing. But I just haven't really figured out the scaling options in OBS and the best ways to capture clips while the computer switches between resolutions, or the best settings to not introduce compression artifacts (while also not resulting in massive uncompressed files that Resolve won't even recognize). Well, I'll keep reading. But thanks to you guys, I definitely have something that I know is going to work for me in the end.

Does anybody know of any good PCIe x1 capture cards?

I would get one of those Datapath cards, since they can also capture 15 and 24 kHz RGB, but they require a PCIe x4 slot, and the only free slot my desktop has is an x1 slot, since the only suitable slot (an x16 slot) is already taken up by the graphics card.

I do have an older desktop with a free x16 (with x8 speed IIRC) slot, but I don't want to dig it out...

cuba200611 wrote on 2021-04-13, 00:46:

Does anybody know of any good PCIe x1 capture cards?

I would get one of those Datapath cards, since they can also capture 15 and 24 kHz RGB, but they require a PCIe x4 slot, and the only free slot my desktop has is an x1 slot, since the only suitable slot (an x16 slot) is already taken up by the graphics card.

I do have an older desktop with a free x16 (with x8 speed IIRC) slot, but I don't want to dig it out...

My Magewell Pro Capture HDMI is 1x (PCIe gen 2.0 recommended though): https://www.magewell.com/products/pro-capture-hdmi