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Atari Emulation of CRT Effects On LCDs

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."

23 of 226 comments (clear)

  1. xscreensaver's Apple ][? by orospakr · · Score: 5, Interesting

    What about the Apple ][ screensaver?

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

    I think it did something very similar.

    (hey, first post!)

  2. Great use of tag by RenHoek · · Score: 3, Insightful

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

  3. But why!?!?!? by xetovss · · Score: 4, Interesting

    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/ . 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

    1. Re:But why!?!?!? by Sycraft-fu · · Score: 5, Insightful

      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.

    2. Re:But why!?!?!? by Daniel_Staal · · Score: 4, Informative

      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.

      --
      'Sensible' is a curse word.
    3. Re:But why!?!?!? by fractoid · · Score: 5, Insightful

      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.

      --
      Rampant carbon sequestration destroyed the Dinosaurs' tropical paradise. I'm here to help repair the damage.
    4. Re:But why!?!?!? by bonch · · Score: 3, Informative

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

  4. Overdid it. by nausea_malvarma · · Score: 3, Insightful

    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

    1. Re:Overdid it. by ElectricTurtle · · Score: 3, Insightful

      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...

      --
      I support the Slashcott and will not be reading or commenting from 2/10/14 to 2/17/14. Beta is steaming pile of dog shit
    2. Re:Overdid it. by ktappe · · Score: 4, Interesting

      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.

      --
      "We can categorically state we have not released man-eating badgers into the area." - UK military spokesman, July 2007
  5. Why bother? by Anonymous Coward · · Score: 3, Insightful

    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?

  6. The ultimate test! by Jah-Wren+Ryel · · Score: 3, Funny

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

    --
    When information is power, privacy is freedom.
  7. Re:Unfortunately, CRT is still the best for gaming by MobileTatsu-NJG · · Score: 4, Insightful

    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 like to lick butts!" by MobileTatsu-NJG (#32700246) (Score:5, Informative)

  8. No pedantry needed... by rbarreira · · Score: 3, Insightful

    ... since they were referring to realistic emulation... meaning closer to the reality of the system being emulated.

    --

    The AACS key is NOT 0xF606EEFD628B1CA427BEA93A9CA9773F
  9. Comment removed by account_deleted · · Score: 4, Insightful

    Comment removed based on user account deletion

  10. It's been done before by Sycraft-fu · · Score: 5, Informative

    One of the most widely used Blargg's NTSC libraries. Many console emulators make use of them. This new one just looks to be more advanced than most of the preceding ones.

  11. Re:Does this mean i can use a lcd in my mame cabin by Khyber · · Score: 3, Interesting

    Wait, you need two ports taken up so you can display on a 30" screen?

    Crap, I'm still using a single 15-pin D-SUB to connect to my 32" 1080p LCD on my old computer.

    --
    Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
  12. Re:Does this mean i can use a lcd in my mame cabin by Anonymous Coward · · Score: 5, Funny

    Wait, you need two ports taken up so you can display on a 30" screen?

    Crap, I'm still using a single 15-pin D-SUB to connect to my 32" 1080p LCD on my old computer.

    I'm betting you're using a Monster Cable. That other guy has to use two because he is using normal cable.

  13. Re:Next up: Lag emulation by guruevi · · Score: 4, Funny

    Emulating old stuff:

    286 without math co-processor - Install Vista
    trig function lookup tables - You would be surprised that they are still being used (both in paper and in code)
    film - you mean like 35mm? There are filters in most semi-advanced photo programs that will emulate this.
    typewriters - http://www.instructables.com/id/Typewriter-Computer-Keyboard/
    horse dung smell in the streets - Go live in NYC, open the window and take a deep whif
    Morse code - Well, everything is still binary these days so technically it's similar to really fast morse code.
    the black plague - Swine flu?

    --
    Custom electronics and digital signage for your business: www.evcircuits.com
  14. Re:Unfortunately, CRT is still the best for gaming by Bigjeff5 · · Score: 3, Insightful

    Since the fastest runners in the world have reaction times in the 170-190ms range, and unofficially at least the fastest "clicks" 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 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.

    --
    Security is mostly a superstition... Avoiding danger is no safer in the long run than outright exposure. - Helen Keller
  15. Re:Unfortunately, CRT is still the best for gaming by Nicolay77 · · Score: 4, Informative

    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.

    --
    We are Turing O-Machines. The Oracle is out there.
  16. Re:Unfortunately, CRT is still the best for gaming by RzUpAnmsCwrds · · Score: 4, Insightful

    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).

  17. Re:Unfortunately, CRT is still the best for gaming by Mprx · · Score: 3, Informative

    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.