Capturing video from Arcade Boards

Now, this is an idea that just popped into my head, and my camera isnt working, so work with me here.

My capture equipment cant capture straight RGB (=me sad)

It can capture 480i component though, so if thats the best I can get, so be it.

The problem is, 1) I dont want a full fledged supergun when I have 4 cabinets in 1 room as it is, but mostly 2) Capturing shooting (gun) games would be quite difficult, as I believe many rely on the monitor..

My solution would be this.

You take the arcade board, plug that into a supergun with the neobitz encoder for component out. Split the signal**, have part going to the component (and sound for that matter, which isnt as big of a deal), which would give me what I need to capture, but then pass everything, power, RGB, controls, sound, everything, to the cabinet. This eliminates the need for controls and a power supply for one, plus 2, space is too damn limited in my room right now. Plus, it would allow me to play the gun games as I should, while capturing the video. On the plus, I can then capture whatever (Jamma) arcade game.

Now the ** part..

**How could I ensure that the signal could be split without degrading the quality too much on either end. Would some sort of signal boosting be required? I figure the quality would go down a bit, thats something Id have to deal with, but so long as its decent, and would still work with most games, I think it would be a good compromise.

Any ideas or problems that you guys feel I may run into? Its a decent concept anyway, for an issue Ive been toying with in my head for a while.

 

I have heard that arcade RGB signals don't like to travel too far.

ie: I just read a thread on KLOV where a gentleman was selling a 10 foot jamma harness extender that he had built so he could leave his jamma boards in his closet and play them on a cab. He said the RGB signal became so weak that it didn't work well.

I suppose that would mean that you would have to place your neobitz inside your cab...or at least as close to it as possible. That would be easy though, as I imagine it just requires 5v...which is plentiful in a cab. Real simple to wire.

The only question in my mind then would be whether a composite, S-video, or component signal would travel the sort of distance that you would want it to. My logic says, if you have a neobitz already, to connect a set of loooooong wires...and see how the signal comes out.

As for actually tapping the signal, I think I would tap it by adding a connector in where the RGB connects into the monitor. Seems like the easist place to get at the signal.

I have, very hackily, run wires from my burgertime pcb to a supergun while the monitor in the game was going as well, and I didn't notice any major issues...but I wasn't really looking at video quality.

If you would want to run the RGB lines a long distance, I'm sure you could find suggestions on how to amplify it here, klov, or maybe neo-geo.com

Note: I hear Jrok's encoder works with more games...so you might want to try that if you don't already have a neobitz.

 

Think simpler.

I had a drawing, but photoshop was so kind as to freeze. Anyway

Take the Jamma Edge on the game board. Plug that directly into the encoder box, which goes right to another jamma edge with as little distance between the two as possible, probably no more then 2 or 3 inches. Then that second jamma edge plugs right into the cabinet.

So really, its just a box inbetween the Jamma connections. Very small, very discreet, so the signal wont be distorted so much over any length.

The worst distortion would be going from the component cables to my PC, but even that is close to my arcade cabinet, no more then a few feet. So really, that leaves how much of the connection would be distorted by the split. Id imagine its not too terrible, even if its noticeable, considering people split an RGB signal through two cabinets.


And yeah, the encoder isnt decided on. Its just something that popped into my head.

 

Do you have a rgb to component adaptor? I have a problem...
I want to capture video from my supergun,which outputs to a scart.
My problem is that my capture card inputs rca or s-video.i have tried several adaptors but none works.:-(

 

You need some sort of signal conversion. I plan on buying a Neobitz / Jrok converter to turn the RGB into something my capture equipment can use. Youll need something that outputs RCA or S-video, which there are lesser models of the encoders above that do just that

 

a very quick n simple Opamp circuit will boost the signal well enough, and so long as you aren't using a cheap opamp it won't degrade the signal.

 

I'm just thinking that it might be a whole lot of extra work to make a box with a jamma edge input, with the encoder inside...and then have it output jamma on the other side...running so many wires though the box...when all you really need is eight of them, including power.

I just favor touching as little as possible and simply putting a tiny, extra harness in between the rgb connector and monitor that has wires that shoot out that would hook to your encoder. I suppose yours might be better for long term use though.

 

Most videocapture devices only supports PAL and NTSC and there is not many arcadegames that use those two standards... my capturecard has alot of sync problem with almost all of my games.

 

If the video is being converted, its less of an issue. Ive got a good capture card, no worries there

 

To split the signal you need to first load it to the proper level (1K pot? arcade video varies...), then you need to take two amplifiers (6x video opamps for RGB) to double (gain = 2) the signal, into a series 75 ohm resistor and 220uF capacitor. Then both outputs will be hopefully 1Vpp into 75 ohm suitable for a TV. Doing this is very expensive though! If you will ALWAYS use the two display setup, you can use only 3 opamps, change the output resistor series to 37.5 ohm (2x75 ohm in parallel), and connect the two displays in parallel. (This assumes that both displays have 75 ohm load resistors, which the arcade monitor probably won't)

Are you sure your capture card doesn't have RGB input? Component requires 3 DACs, the same RGB would so logically it would support RGB as well since it's even easier to decode.

I think the most reasonable way to go about this is to just take a JAMMA edge connector and fingerboard, wire them straight through except for the video/audio wires, and just put together a RGB encoder circuit for S-video which most capture cards have inputs for. If S-video is good enough for TV and movie production it's certainly good enough for a game recording over a capture card! Another thing that's good about an RGB encoder is that it will have an amplifier built in allowing you to use S-video/component/composite and RGB at the same time. I really don't get what the fuss is about S-video quality either, the capture card will certainly be the weakest link in the setup whether you use RGB or not.

 

i know pixel magic made an rgb capture card a while back. someone on gamesx got it and took pics.

 

how about this:
http://www.arcadeshock.com/items/sn...-to-ntsc-converter-rgbntsc-acc-detail.htm?1=1

Expensive though: $250,-

 

Non component. Plus I can make it for cheaper Im just waiting for the money for the encoder board I need.

 

there a simple schematic for RGB to S-VIDEO here http://www.nexusuk.org/projects/rgb2svid/circuit that should be ok for your jamma

 

SVideo = . Id rather spend the money on the component out, as the rest of the adapter is simple to make, or rather, should be.

 

oops my bad, I misread your post. sorry

 

zakk over at shmups (and #shmups on EFNet) uses this and swears by it.
http://www.pluggedin.tv/store/SweetSpot_Video_Processor.html

 

I got a 25$ rgb to s-video encoder board. And that's hooked into a 15$ usb s-video capture device. It captures video and sound at the same time.....yay

 

Svideo = Ive already got a pretty good idea what Im doing with this, its all a matter of getting the cash so.

 

One word - MAME!