Stories
Slash Boxes
Comments

News for nerds, stuff that matters

Slashdot Log In

Log In

Create Account  |  Retrieve Password

Atari Emulation of CRT Effects On LCDs

Posted by samzenpus on Thu Apr 30, 2009 07:50 PM
from the you're-living-in-the-past dept.
thumbnail
An anonymous reader writes "A group at Georgia Institute of Technology has developed a fun little open source program to emulate the CRT effects to make old Atari games look like they originally did when played on modern LCD's and digital displays. Things like color bleed, ghosting, noise, etc. are reproduced to give a more realistic appearance."
*
+ -
story

Related Stories

This discussion has been archived. No new comments can be posted.
The Fine Print: The following comments are owned by whoever posted them. We are not responsible for them in any way.
 Full
 Abbreviated
 Hidden
More
Loading... please wait.
  • A program to make look CRT like teletype output (or DEC LA-36)??? Or to make CRT look like Hollerith cards???
    • Re: (Score:3, Interesting)

      by sdpuppy (898535)
      What I want is one that can ply and look like Pong back in the good old days (all staticy with the screen jumping around when the numbers changed!)
  • by orospakr (715849) on Thursday April 30 2009, @07:54PM (#27781749) Homepage

    What about the Apple ][ screensaver?

    http://www.jwz.org/xscreensaver/screenshots/ [jwz.org]

    I think it did something very similar.

    (hey, first post!)

  • Great use of tag (Score:4, Insightful)

    by RenHoek (101570) on Thursday April 30 2009, @07:56PM (#27781765) Homepage

    I think this is one of the most justified uses of the 'brokenbydesign' tag ;)

  • by Anonymous Coward

    And does their program eliminate motion blur and the poor contrast of LCD to make it looks like a CRT?

    • by MobileTatsu-NJG (946591) on Thursday April 30 2009, @08:24PM (#27781981)

      And does their program eliminate motion blur and the poor contrast of LCD to make it looks like a CRT?

      No but the 21st Century did.

        • I haven't seen a flatpanel yet that in objective terms of quality comes anywhere near a CRT.

          Try looking at a new one then. The colour isn't _quite_ where CRTs were but it's within spittin' distance. Ghosting hasn't been a problem for 5+ years.

        • Re: (Score:3, Interesting)

          How are you measuring that? I'm sitting here in a bullpen surrounded by 2 year old ~$600'ish (at the time, they're like $200-$400 now) LCDs and a couple of really expensive CRTs. The CRTs are blurry and dim in comparison, by a sickening amount I might add. Actually they bloom a bit, making everything a bit soft. There's not one aspect of those CRTs I'm envious of, and these aren't cheapies.

          I haven't even had a laptop in the last two years with display that makes me look fondly at CRTs. The closest I've

        • by RzUpAnmsCwrds (262647) on Friday May 01 2009, @01:38AM (#27783895)

          Your 21st century seems a lot nicer than my 21st century. I haven't seen a flatpanel yet that in objective terms of quality comes anywhere near a CRT.

          CRTs have better black levels and better colors. On the other hand, they have fussy geometry adjustments (and you can never get them as perfect as an LCD), moiré patterns, and are generally much fuzzier than LCDs.

          My LCD provides a sharp, high-resolution image with low power consumption in a small package at a low price. All of those factors (sharpness, resolution, power cosumption, size, price) matter more to me than the areas where CRTs continue to lead (color reproduction, black level).

        • I play rhythm and fighting games on my LCD all the time. They're completely fine.

        • Re: (Score:3, Insightful)

          by Khyber (864651)

          I've been working on an 800+ character MUGEN game for quite some time, now. My primary monitor is a 32" 1080p LCD made by Samsung, and there are NO timing issues. I even have an X-Arcade controller for testing. No lag. That's like 50 feet of wire/cable between controller and monitor.

          The biggest problems most games have these days on LCD screens is their own inputs. Every guitar hero/rockband controller I've touched likes to double-strum, even on touchier movements. While DBZ BT3 on the Wii is great, part of

        • by Bigjeff5 (1143585) on Thursday April 30 2009, @10:41PM (#27783041)

          Since the fastest runners in the world have reaction times in the 170-190ms range, and unofficially at least the fastest "clicks" [humanbenchmark.com] are all above 100ms (I averaged 232ms myself, just below average), I'd doubt you could notice, let alone be affected by, a 10-50ms disparity.

          And I'm not sure how you can say 2ms response time leads to a 50ms disparity anyway, that doesn't make sense. Hell, there was a 70ms difference between my slowest and fastest clicks, and I couldn't notice the difference. The tech to get the response times so low does tend to jack colors and produce some odd artifacts, but none of those relate to how quickly it displays the data on the screen, not as far as I've ever heard anyway. Since the color/artifacting issues are relevant, and since 15ms vs 2ms is not noticeable, it's better to pick a 15ms LCD anyway.

          Plus, a frame will generally be displayed at least 10 times, if it is displaying at 15ms, before you can actually react to it. Again, the response time argument for not going LCD is tired and nearly worthless.

          The problem is probably just that you've been reading weird crap about LCDs, and haven't used them much yourself. Most likely to keep from justifying an upgrade.

          Actually, if you really want to prove me wrong (and find out for yourself if the LCD response time is really the issue), go to Humanbenchmark.com [humanbenchmark.com] and compare your OWN clicks on a CRT with your OWN clicks on an LCD. I'm assuming you have access to one, of course, but it shouldn't be hard to get access to one anyway.

          I'm betting there is less than a 5ms difference in your 10 click averages.

          • The tech to get the response times so low does tend to jack colors and produce some odd artifacts, but none of those relate to how quickly it displays the data on the screen, not as far as I've ever heard anyway.

            The 2ms 'response time' is just about the pixels response to the electrical signal. In other words, those 2ms means: this LCD can change a pixel from black to white in 2ms. It doesn't mean: this LCD will change the pixel 2ms after the computer or console tells the screen to change the pixel.

            Since a couple of years, LCDs have a 'image enhancement' mode that adds some lag, from 40 to 105 ms. This is precisely to have a buffer that lets the chip preprocess some stuff and reduce ghosting or other things. I think that the 15ms or less to change a pixel is also possible only because of this processing.

            You can't say that 105 ms is not noticeable, and this is probably what the GP is talking about. And DLP HDTVs seems to have up to 250ms of lag.

            However, modern LCDs have also a 'gaming mode' with (virtually) no processing lag, but with the usual ghosting and other LCD classic issues.

          • by Mprx (82435) on Friday May 01 2009, @05:20AM (#27784855)
            LCD response time, latency and motion quality has nothing to do with human reaction time. Humans can distinguish differences in time interval much shorter than their reaction time. Look at graphs of beat length variance of skilled drummers.
  • But why!?!?!? (Score:4, Interesting)

    by xetovss (17621) on Thursday April 30 2009, @08:02PM (#27781809) Journal

    And to think that it seems all the rage is to be upgrading Atari's with an Svideo board as featured on hack-a-day a few weeks ago http://hackaday.com/2009/04/05/s-video-from-an-atari-2600/ [hackaday.com] . Honestly I don't know why people want to make their TV's look like a 30 year old TV display. The reason for all that bleeding was the circuitry that converted the video and audio signal to RF and then the deconverting of that signal in the TV. It is beyond me why anybody would want to make something look like it did, instead of how it should look. I grew up playing the Atari 2600 and I thought it was fun, but I certainly am not fond of how it looked. I'm just waiting for my SVideo converter board to arrive so I can upgrade my 2600 to look how it should, not how it did. (And I'm still using a CRT TV as well none of these new fangled LCD TV's). - XSS

    • Re:But why!?!?!? (Score:5, Insightful)

      by Sycraft-fu (314770) on Thursday April 30 2009, @08:36PM (#27782095)

      Because old systems counted on it. They were designed around working on low rez NTSC displays. You find that the color bleed and fringing and such helped smooth out the image and make it more natural. When you display it on a modern high resolution LCD it looks extremely blocky. So you emulate the problems with the older technology and you get a better looking picture for it.

    • Re:But why!?!?!? (Score:5, Informative)

      by Daniel_Staal (609844) <DStaal@usa.net> on Thursday April 30 2009, @08:41PM (#27782145)

      Well, in the case of the Atari games, it is fairly obvious that the programmers used the effects to create nicer-looking graphics without going to extra work. Sort of a reverse anti-aliasing effect.

      Take a look at some of the comparison images in the article. The 'Enduro' image is particularly interesting: The skyline looks extremely fake on an LCD, but with the CRT emulation it looks almost realistic. The effect basically gives a continuous-color blend which would be impossible using just the colors available to the program.

      So really, you can argue that this is how the games were meant to be seen like this, and this is actually how it should look.

    • Re:But why!?!?!? (Score:5, Insightful)

      by fractoid (1076465) on Thursday April 30 2009, @09:12PM (#27782407) Homepage

      It is beyond me why anybody would want to make something look like it did, instead of how it should look.

      But this IS how it "should look". It was designed for that display. People want it to look like it originally did for the same reason that people like muscle cars, vinyl records (complete with the hiss and wow and flutter that they try so hard to eliminate), valve amplifiers. It's because sometimes the inaccuracies in equipment change the signal for the better, and people like that.

    • I've played Atari games natively on a color TV set, as well as emulated on a SVGA CRT. I like it both ways. You get a super-clear picture on the computer monitor, but it's nostalgic to play it with the video artifacts that came from the RF input and NTSC. If you value a true historical re-enactment, you kindof need to be able to do this. It's something that you can configure to your preference, so having it as an option doesn't hurt anybody. Even MegaMan 9 had a special mode that allowed you to emulate

    • Re: (Score:3, Informative)

      by bonch (38532)

      This page [slack.net] has screenshots showing the difference. Many games were designed with NTSC artifacts in mind.

  • NTCS filters (Score:3, Insightful)

    by Ailure (853833) on Thursday April 30 2009, @08:03PM (#27781819) Homepage
    Reminds me about the various NTSC filters used in various emulators (such as Nestopia). It's kind of funny how some people strive for simulating the original display, but I have to admit that I personally use the NTSC filter when possible. (and I avoid using filters like super eagle which have a tendency to make stuff look like blobs...)
  • Overdid it. (Score:3, Insightful)

    by nausea_malvarma (1544887) on Thursday April 30 2009, @08:04PM (#27781827)
    The effect is great in theory, but I think they over did it. Old arcade games are certainly a bit blurry, and have some ghosting issues, but this effect makes every little sprite into a pile of fuzzy crap. It's too bad to be true, and it ends up looking fake. Reminds me of those pre-faded jeans, with so much added wear that its easy to tell the wear and tear is not natural. Instead of looking like a pair of old jeans, they look like a pair of new jeans that someone split bleach on. Like these [magickidsusa.com]
    • Yeah, this isn't a CRT emulator. This is a RUN-DOWN, GHOSTED, POORLY TUNED CRT emulator.

      A new, decent quality CRT is still better looking in a lot of ways than a LCD monitor.
      • Re:Overdid it. (Score:4, Insightful)

        by ElectricTurtle (1171201) on Thursday April 30 2009, @08:30PM (#27782039)
        Wow, apparently people are missing the point. They obviously aren't trying to emulate 'new CRTs' what would be the point of that? Have you people forgotten what a 12" MCGA or EGA display from over two decades ago used to look like? I used to have one (MCGA) in working condition as recently as two years ago, and I can say the emulator is pretty close.

        Damn kids don't remember what shit used to look like before VGA, SVGA, XGA etc. came along and spoiled 'em. When I was growing up, I had one color! ONE! And it was the nastiest shade of amber ever conceived! At least I could play Airborne Ranger...
        • Re: (Score:3, Insightful)

          by hairyfeet (841228)

          Yes! preach brother! I grew up watching one of those big ass Magnavox TVs, and this is a pretty perfect representation of what we had in the 1970s. We had bleeding channels, and ghosting, oh and if you weren't careful you ended up with the pattern for something like Pacman "sticking" around for awhile.

          My mom of all people was addicted to Yar's Revenge and Donkey Kong JR (we had the ColecoVision [wikipedia.org] with the 2600 expansion module) and she would sit there playing Yars late at night and I would get up to watch car

          • Re:Overdid it. (Score:5, Interesting)

            by ktappe (747125) on Friday May 01 2009, @12:40AM (#27783605)

            You are missing the point. It looks NOTHING like a real television CRT from back then. The effects are just wrong.

            Yes, it really does. As a child of that era I feel quite qualified to say "Yup, that's what Pac-Man on my neighbor's Atari 2600 on their 1970's Sears TV looked like." It looked fuzzy, we knew it looked fuzzy, but we still loved it. It was quaint even when it was new, and we knew that but it was seat-of-your-pants gaming. This was the late 70's...Disco was in; everyone's clothing & carpets & cars & wood paneling were brown; Commander Adama was still played by Lorne Greene; Trans Ams were cool; our games were blocky & fuzzy. The world was right.

            Oh and computer displays never had artifacts like that. I've had every PC display type from CGA to WUXGA

            You're right, they didn't. As a dozen other posts have pointed out, this is meant to emulate what computer graphics sent to a TV through a composite cable looked like. You remember those Radio-Shack metal switchboxes that went between the antenna and the TV's RF input that let you plug in a single cable from the Atari/Commodore/whatever? That one cable carried audio, chroma, and luma, all bleeding into one another. Thus this type of bleed. Nothing to do with Hercules, CGA, EGA, VGA, etc.

      • I think it's specifically trying to reproduce the look of an old television CRT.
    • I never did get why they put the fake-wear on those jeans in the one place that lasts longer than everywhere else and then leave the knees and ankle areas completely normal.

    • How old (young) are you? It looks quite accurate to me. Heck, I still remember playing 'TV games' on our old black and white TV.

  • It reminds me of the audio effects that add pops and scratches to music to imitate (badly) the sound of old vinyl.

  • Why bother? (Score:3, Insightful)

    by Anonymous Coward on Thursday April 30 2009, @08:14PM (#27781895)

    Honestly, craig's list is riddled with people throwing away CRT's. Why run a crappy emulation...if that is what you call it, when you can go next door and get CRT?

    • Re:Why bother? (Score:5, Insightful)

      by Bottlemaster (449635) on Thursday April 30 2009, @08:38PM (#27782119)

      Why run a crappy emulation...if that is what you call it, when you can go next door and get CRT?

      Many of these artifacts are not just caused by the CRT, but result from other portions of the path from video RAM to the screen. The emulation creates an even more genuine experience than a computer CRT without compromising the convenience of an LCD.

    • I like my LCD. For any sort of productivity work or modern games, it looks way better than any CRT ever could. So I want to keep it. I don't want to haul out a CRT any time I want to emulate an older system. There's also the problem that computer CRTs won't do the trick. They are higher resolution, and have better signaling than NTSC sets. So they too will offer a different image than an old NTSC TV.

      There's no need to bother with all the physical hardware if it can just as easily be simulated by the compute

  • by CrazyJim1 (809850) on Thursday April 30 2009, @08:19PM (#27781935) Journal
    bunk bunk bunk. Do do do weep.

    Isn't it sort of ironic that people want perfect emulation of Atari 2600 PacMan when Atari 2600's PacMan was notoriously not like the arcade version? Even NES didn't do emulation well. I think the first well emulated game I ever played was Street Fighter 2 on SNES.
    • The only place where i've heard about the atari 2600's pac man has been on like the top 10 lists of terrible games or worst games of all time or whatever because it so wasn't the arcade version.

      The only thing I was wondering was where could I play the emulated games?
  • by Jah-Wren Ryel (80510) on Thursday April 30 2009, @08:19PM (#27781951)

    So, can I get burn-in on my LCD monitor now?

  • Nice (Score:3, Insightful)

    by Trogre (513942) on Thursday April 30 2009, @08:22PM (#27781965) Homepage

    Looks similar to the efforts the xscreensaver developers, with their m6502 and Apple2 hacks that simulate CRT artifacts such as static, colour separation, and shear.

  • by derGoldstein (1494129) on Thursday April 30 2009, @08:40PM (#27782135)

    Here's a list of stuff I'd like to emulate, for the sake of nostalgia:

    286 without math co-processor
    trig function lookup tables
    film
    typewriters
    horse dung smell in the streets
    Morse code
    the black plague

    Get on it!

  • I don't get it... (Score:2, Insightful)

    by theNetImp (190602)

    I don't remember my Atari looking like that on my TV. Sure it wasn't LCD perfect but it didn't suck that that does.

  • Now we need a Hercules video card [wikipedia.org] emulator for wordprocessing and CAD.
  • by phr1 (211689) on Thursday April 30 2009, @09:20PM (#27782471)
    Modern web frameworks like Cobol on Cogs [coboloncogs.org] already do burned-in CRT emulation and various other effects too. ;-).
  • Vector? (Score:3, Insightful)

    by Tablizer (95088) on Thursday April 30 2009, @09:52PM (#27782669) Homepage Journal

    Vector graphics may be the most difficult to emulate because of the potential brightness of specific spots. The brightest white on most LCD monitors cannot compare to such a spot. Asteroids is probably the most famous vector game. Basically, the electron beam could be controlled to "draw" the game via lines and dots instead of merely scanning back and forth at a fixed pace like traditional CRT's. The beam could "dwell" on a specific spot or line if needed, making it glow like nobody's mamma.

    • by Nimey (114278)

      I had one of those monitors. I do love Trinitron tubes, but this one eventually had something funny happen to the EDID information and it became unable to do more than 60 Hz.

      • Re: (Score:3, Interesting)

        I'm still keeping my ibm p260 alive until something that comes closer to CRTs than flatpanels is out. Even built my own windas cable to fix the g2 issue.