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#1
capture card/screenshot advice
Geschrieben am: 06.10.2009 3:52
VB Gamer
Dabei seit 14.12.2005
40 Beiträge
10+ Game RatingsLong Time User (13 Years)
I hope someone in here has experience with this sort
of thing and feels like giving me some advice.

I need to be able to take high resolution screenshots
of old-school console games for a project im working on
and im kinda stuck.

It would be real nice to just be able to hook rca jacks
right into my pc, press printscreen, and import right
to imaging software, but thats too simple.

I just bought a Dazzle dvd recorder/capture device,
and the video quality sucks... im more concerned with
quality screenshots.

It would also be nice to play old consoles right on my pc
if I could. Any help or ideas?
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#2
Re: capture card/screenshot advice
Geschrieben am: 06.10.2009 8:22
Virtual Freak
Dabei seit 14.10.2008
91 Beiträge
Long Time User (11 Years)
I got a gamebridge but its pretty similar to the dazzle capturing device, and my gamebridge doesnt do NES SNES 64, the old ones anyway..

high quality im not so sure sorry, the only way i know how to play videogames on the computer would be via emulators.. or video capturing devices such as gamebridge and dazzle.

out of interest what kind of project are you doing, what do you have to do?
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#3
Re: capture card/screenshot advice
Geschrieben am: 06.10.2009 11:04
PVB Elite
Dabei seit 26.07.2003
USA
1465 Beiträge
PVBCC EntryCoderContributorSpecial AchievementTop10 PosterHOTY09 EntryLong Time User (15 Years) App Coder20+ Game RatingsPVBCC 2013 Entry
Using the phrases "high resolution" and "old-school console games" in the same sentence is slightly oxymoronic.

For example, the SNES has a max resolution of 256x240. If your capture device is at least that resolution, you should be able to extract close to 100% of the original pixels (except the actual color values will vary due to the analog video signal). Also, I would use the lowest capture resolution you can and (for stills) use a program like IrfanView to scale it up, if needed.

What consoles, specifically, are you using, and how are you connecting them to the capture device? I would assume that S-Video is the best the capture card can do, without some hacking, so you're going to be limited by that interface no matter what card you use. I don't know of any capture cards that do PAL/NTSC RGB out of the box.

You might try getting the least amount of cable possible between the console and the capture device, i.e. use something like a gender-changer that's basically two connectors back-to-back (except the SNES has a proprietary cable you'd have to hack, but you get the idea).

For consoles with RGB output, you could use one of these:

http://www.converters.tv/products/cga_to_vga/480.html

Hooked to one of these:

http://www.pixelsmart.com/vga.html

(Although, based on the PixelSmart description, you may be able to get by with it alone...)

One more thing: When console video is involved, this site is your friend

EDIT: Kind of expensive, but here's an all-in-one solution: http://www.pluggedin.tv/sweetspot/features/index.html (found via: http://shmups.system11.org/viewtopic. ... 182bdd950dfa5f7f4994fabdc)
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#4
Re: capture card/screenshot advice
Geschrieben am: 06.10.2009 16:19
VB Gamer
Dabei seit 14.12.2005
40 Beiträge
10+ Game RatingsLong Time User (13 Years)
First, I would like to change 'high-resolution' to
'close-up'.

second, console types.
-nes
-snes
-n64
-gamecube
-genesis
-saturn
-dreamcast
-3d0
-xbox (and 360)
-ps1,2,3.
-anything that uses rca jacks (composite)

Shouldn't a device capable of playing these types
of consoles (via the pc, not just the monitor)
put a useable image on the screen and I
could just press printscreen?
Does such a device exist?

the limiting factor you were talking about
is actually the rca jacks. I dont have s-video cables for
lots of these consoles- so the standard is r/w/y rca jacks.
obviously, that is quite a bottleneck in the picture
quality i will be able to get. I just want to get the best I
can from them.

thanks for help so far. I need to play with this
thing (dazzle) some more, but so far it seems
way to small of an image to work with.

So far that 'sweetspot' seems to be pretty badass, but im still researching.
Bearbeitet von pocket am 06.10.2009 16:41:34
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#5
Re: capture card/screenshot advice
Geschrieben am: 06.10.2009 17:23
PVB Elite
Dabei seit 26.07.2003
USA
1465 Beiträge
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Okay, now you have to define "close-up"

If you want a picture that's bigger than, say 256x240 from an SNES, you're just going to be "making" pixels which simply aren't there. There are dozens of algorithms for "intelligently" making those extra pixels, but there's always going to be some kind of picture degradation.

Also, most or all of said algorithms are going to produce extra poor results from an NTSC composite signal, because of the decreased color bandwidth. And it gets even worse if your capture card uses lossy compression on-board.

Commodity S-Video cables for most of the consoles in your list are actually not that expensive. Plus, the one for SNES will also work on N64 and GC, and it's the same for PS1/2/3; so it's like getting six cables for the price of two! I've even seen one cable that does all three Nintendo consoles, all three Sony consoles, and Xbox (and 360 if it's backwards compatible)!

Also, about the "print screen" thing: I'm not sure about a USB one, but the ISA/PCI/AGP capture cards I've used overlay the video directly on the video card's output, so it doesn't even exist on the level at which "print screen" operates.

Doesn't the adapter have a Twain driver or something for capturing stills? If not, you can use Media Player Classic or VLC to take stills from the video feed.

But seriously, why can't you just use a screen-shot from an emulator (except in the obvious cases)?
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#6
Re: capture card/screenshot advice
Geschrieben am: 12.10.2009 19:01
VB Gamer
Dabei seit 14.12.2005
40 Beiträge
10+ Game RatingsLong Time User (13 Years)
RunnerPack:
thanks for your help so far.
Surprisingly, I dont have any s-video cables for any of my systems :(

This is a screenshot from a gamecube using composite and the 'dazzle'. Once I have some s-cables, I will post the difference.
Printscreen works while running the dazzle, so Im not really recording with it, just using it to play the games.

The whole thing seems to contradict logic: I dont see the difference between a pixelated digital image in a game, and a bitmap- type image on a computer. I would think you would get a perfect translation from one to the other, as long as the cables themselves can support the resolution of the image, and I would think composite would be adequate for older games. Forgive my ignorance... but hey, Im trying to learn. I just have too many projects at one time to focus. Thanks for the insight, though.

Datei anhängen:



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#7
Re: capture card/screenshot advice
Geschrieben am: 13.10.2009 21:54
PVB Elite
Dabei seit 26.07.2003
USA
1465 Beiträge
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There are many reasons you can't get a perfect image from a composite source (or even SVideo, though it's much better quality).

For one, the image is RGB in the console, but NTSC uses a whole different color space. It describes colors in terms of their hue (basically the wavelength; think "Roy G. Biv" ), saturation (how "pure" the color is) and brightness. The conversion between color spaces is subject to precision losses both ways.

Also, since the color TV system was tacked on to the existing B&W TV standard, called RS-170, most of the bandwidth of the transmission line (the yellow-ended cable from your console) is devoted to just the brightness. This is why colors can shift and smear while the basic "gray" part of the picture (the brightness) stays the same. SVideo solves this by putting the "luma" (brightness) and "chroma" (color; hue+saturation) on separate (hopefully shielded) wires. Component video is the next step up. It splits the chroma into two separate signals, for a total of three. It has about three times the bandwidth of composite and is about as good as NTSC gets; unless you count the balanced cables they (used to) use in TV stations and the like.

Finally, since all of this image data is represented as a voltage on the aforementioned wire, any electrical noise that changes that voltage affects the image - hence my recommendation to use very short cables.

Before I got a digital camera, I used to use a camcorder and capture card to take photos. If my subject was motionless (e.g. eBay photos) I would capture multiple stills of it and then use software to average them together. Since the image I wanted was the same, but the noise changed each frame, this cleaned up the image quite a bit. I still had to fix the histogram, sharpness, etc., of course, but it was a big boost in quality.

That brings up another thing: don't hesitate to try post-processing your images. It can be especially effective on the older consoles, since you know what the original should be like (e.g. the NES is limited to 16 colors).

I hope you can get something to fit your needs.
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