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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."
What about the Apple ][ screensaver?
http://www.jwz.org/xscreensaver/screenshots/
I think it did something very similar.
(hey, first post!)
I think this is one of the most justified uses of the 'brokenbydesign' tag ;)
And does their program eliminate motion blur and the poor contrast of LCD to make it looks like a CRT?
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
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...)
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
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?
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.
God spoke to me.
So, can I get burn-in on my LCD monitor now?
When information is power, privacy is freedom.
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.
"Nine times out of ten, starting a fire is not the best way to solve the problem." - my wife
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)
... since they were referring to realistic emulation... meaning closer to the reality of the system being emulated.
The AACS key is NOT 0xF606EEFD628B1CA427BEA93A9CA9773F
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.
A bullet may have your name on it but splash damage is addressed "To whom it may concern."
Comment removed based on user account deletion
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!
Entomologically speaking, the spider is not a bug, it's a feature.
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.
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.
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 come is ghosting on the PSP.
"I like to lick butts!" by MobileTatsu-NJG (#32700246) (Score:5, Informative)
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.
Modern web frameworks like Cobol on Cogs already do burned-in CRT emulation and various other effects too. ;-).
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 the control interface lags when doing a gesture movement, or double-taps for you if you press a button only once.
Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
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.
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.
Table-ized A.I.
The highest res mode was black and white only, but due to limitations of the CRTs used in TVs at that time, if the pixels weren't a solid block, the color would shift to something not-white.
Back then I wrote a drawing program that took advantage of the artificing to draw in color. I knew which pixels in a block could be turned on or off to generate one of up to about 16 colors. Obviously, the smallest blocks were only 5 colors. (Red, Green, Blue, Black, White) So the more detail you wanted your drawing, the less colors available.
If these guys can properly emulate that program properly (sorry, don't have a copy anymore), then they've definitely hit the mark with their attempt.
Ah, the ancient days of programming when the kid with 16k memory was the uber133t. (Of course, back then, you used a different dialect of what eventually became l337 to save precious bytes of memory. And Ascii-bombing was used to play mindgames on the BBSs.)
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!)
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
Ghosting hasn't been a problem for 5+ years.
Black-level is still a huge issue. Manufacturures have been trying to correct bad contrast ratio by amping up the backlight, screwing up the blacklevel even more.
It's gotten so bad that TVs have begun cheating and dimming the backlight during dark scenes. Which just turns them into a muddy mess.
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.
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).
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.
This is NOT emulation of CRT effects! This has absolutely no basis in reality. This effect was produced by some guy randomly throwing full-screen convolutions at a wall and seeing what "looked right" to him. The only legitimate emulation of CRT effects is that which is provided by blargg's NTSC emulation libraries, and is used by such emulators as ZSNES and Nestopia. This is not in any way "emulating" a CRT or NTSC signals. It's just what some guy thinks it should look like.