Videogame history project successfully emulates CRT on LCD
See old games how they were meant to look
We thought fuzzy images went out with cathode ray tube monitors, but a team of boffins at the Georgia Institute of Technology have developed an app that mimics the visual characteristics of CRTs on today crisp, pixel-perfect LCD screens.
And it's all been done in the interest of historical research, specifically the evolution of videogames.
According to GIT Associate Professor Ian Bogost, emulation software is all very well at allowing modern historians to examine old videogames, but they don't give you the true feel of playing an arcade game or 8-bit computer programme, all of which were orginally displayed on CRTs, either monitors or TVs.
More to the point, many of them were written to take advantage of the quirks of CRT display technology.
To change that, GIT coders Edward Booth, Michael Cook, Justin Dobbs, Will Rowland and Prince Yang took the open souces Atari VCS 2600 emulator Stella and tweaked the graphics routines to emulate phosphor glow, colour bleed and the noise associated with hooking a CRT up to a source through an radio-frequency modulator.
Georgia Institute of Technology's CRT emulation in action
Click for full-size image
Pics posted by Bogost on the GIT website show how well the team managed to recreate the look of CRT on LCD, but he said you really appreciate the difference when you play the games.
Oldsters will be able to relive youths misspent in arcade halls, while younger players will get to game the way their dads did. Researchers into videogame history will be able to see games how they would have appeared when released.
Bogost said the five coders were working with the Stella development team to get their modifications incorporated into the emulator's official release. You can download Stella here.
We're anticipating the code being incorporated into a future Blu-ray Disc playback app to allow the latest HD movies to be viewed in VHS-o-Vision. ®
COMMENTS
Re: CRT
How to get it out of the flat? What floor are you on? Make a game of it. Take bets on how close you can get to the sunroof of your landlord's AMG.*
*Game works best from 8th floor or higher, due to the effects of wind and the pleasant sound it makes when you hit the bullseye.
CRT
My large widescreen Sony CRT based television is still going strong and I've calculated I've had it nearly 11 years. And no sign of it packing up. LCD's eat your heart out.
F**k knows how I'm gonna get it out of my flat when it does finally die! It's that big and heavy.
Lightguns and reflections
The most important difference is that using a CRT allows the use of a proper light-gun. You can't beat TimeCrisis (unless you work for the Metropolitan Police and head to your nearest tube station).
As for reflections; my old CRTs have a lovely anti-reflection coating meaning I can sit in a bright room and work all day. The new LCD types; especially this laptop mean I have to sit in a dark room unless I want to use it as a mirror.
Can't emulate the low latency of CRT on a LCD
I'm was an avid 8bit gamer, and one thing that has gotten worse and worse (and worse) since I were a lad is 'thumb to eye' latency, or, how long a button press on the controller takes to make a change to the image on the screen, and register in the old noggin.
Lets take the 8bit SNES, connected to a CRT - its the best case, 'thumb to eye' was as low as 2ms (0.002 seconds) and at worse 18ms (PAL) or 14ms (NTSC) for a typical 2D game (VBLANK is 2.5ms).
Connect a SNES to a LCD TV, and you now have the TV's frame buffer in your way, plus the delay to change the LCD image, and if you don't have a 'game mode' on the TV, a multi-field deinterlacer too.
This adds 16~20ms to the delay, at a bare minimum, typically double that, and a good deinterlacer will add upto 40ms, enough to need the TV to buffer and delay the audio so it does not go out of sync.
Ignore the '5ms latency' claims of the manufacturers, they only measure grey to grey, black to white, even on a modern set, is still around 30~40ms.
Now go to 3D, at 30 fps, and due to 3D being renderd to a back buffer, you can add another 30~40ms to the pipe, sometimes another 30~40ms if the game buffers its graphics commands for a frame.
Put it all together, and delays of over a 10th of a second (100ms) are not uncommon in modern video games, on modern display hardware.
So, if you ever wondered why the good old games 'felt' better, IMHO, this is why.
Plasma, and OLED offer the best hope for this, but unless the 'Game Mode' on those TV's emulates the immediate display of the image signal, that was inherent in CRT we will never get back the to twitch gaming of yesteryear.
A step in the right direction
I hope they provide the source and would love to see this integrated with most emulators.
It should allow tweaking of the parameters and come with presets for different types of TVs.
Those kids that don't get of my lawn won't care much but I thank these guys (and emulator coders) for making my childhood dreams come true.
