VGMaps

General Boards => Mapping Tips/Guides => Topic started by: on June 26, 2009, 09:25:01 AM



Title: The color difference between NES emulators
Post by: on June 26, 2009, 09:25:01 AM
I'm embarrassed about the problem.



Here are some screenshots captured from some common used emulators (VirtuaNES, FCE ultra, NNNester) and some emulators that maybe not so popular.



http://img504.imageshack.us/img504/2214/fcemulators.png



VirtuaNES, ZYH and G-NES display the same color, but the other 5 emulators' colors are not the same from each other. May I speculate VirtuaNES get the right color?


Title: RE: The color difference between NES emulators
Post by: Will on June 26, 2009, 10:22:57 AM
The NES emulator "Jnes" is one of the different colour emulator with a more orangey tint to the colours. If you take a look at the differences in colour in Ericloux's Ninja Gaiden maps and mine the comparison will be a lot to observe. Personally I don't know what colours are correct but I'm sticking with the VirtuaNES emulator.


Title: RE: The color difference between NES emulators
Post by: DarkWolf on June 26, 2009, 11:53:29 AM
Consoles generally have a smaller color space than modern computers.  For example the Genesis only uses 3 significant bits for RGB values.  Since modern devices generally use 8 bits for each RGB color, you have to expand the smaller range to fit the larger one.  There really isn't any correct way to do that (although I'm sure someone could argue otherwise).


Title: RE: The color difference between NES emulators
Post by: Revned on June 26, 2009, 12:06:45 PM
I don't know the details, but it's not just a lower bit-depth for the NES. It used a different color space than just RGB, and there is no 'correct' way to translate between the two.



I tested several palettes for my Mega Man maps. There are lots of them out there, but I found them to generally be divided into two groups -- the 'dark' ones and the 'bright' ones. I would suggest experimenting with different emulators and palettes, and choose based on what you think looks best. I ended up slightly tweaking the palette here until it looked like I wanted.


Title: RE: The color difference between NES emulators
Post by: snesmaster on June 26, 2009, 12:47:48 PM
I have found I like the colors from FCEUX the best.  I stick with that to make all the games I map consistent.


Title: RE: The color difference between NES emulators
Post by: TerraEsperZ on June 26, 2009, 12:53:49 PM
From what I've read, the problem is that unlike all the other, more modern consoles, the NES doesn't use RGB at all to render its graphics. Instead, it generates directly the NTSC (or PAL depending on the region) signal displayed by your TV, which is why the same game would have different colors when played on different TV models and/or with different Tint/Color settings.



Apparently, that's why there's no way to create an accurate RGB palette, since the NES uses a totally different system. It's even harder than matching the colors between a document on screen (an RGB process) and printed (a CMYK process) which both use a different color rendering method and different color space.



Your best bet would be using an emulator with accurate NTSC composite emulation, which I think at least Nestopia does. But if you do, say goodbye to well-defined pixels and hello to fuzzy graphics with artifacts. What was made to look good on TV isn't so hot on a computer display.



As for myself, I use FCE Ultra's default palette. It looks great, and I wouldn't notice if a few colors were slightly off from what I can remember from playing on a real NES a decade ago.



---

Current project: Castlevania: Aria Of Sorrow (GBA)



Upcoming project: Castlevania Legends (GB)


Title: RE: The color difference between NES emulators
Post by: Maxim on June 26, 2009, 12:57:01 PM
In general, emulators convert RGB by extending the range from n bits to 8 bits per channel. There are a few ways to do that, but for speed a lot of emulators do a lazy left shift, which results in white not being 255,255,255.



The NES works in an HSL type colour space. There are standard ways to convert that to RGB; the problem is that the NES video chip didn't necessarily output things that match this "perfect" conversion, and a lot of emulators may use less accurate, faster conversions.



The video chip accuracy thing applies to pretty much every console, though. When you add in things like NTSC hue adjustments and analogue effects within the video hardware, it's pretty much impossible to get it 100% accurate.


Title: RE: The color difference between NES emulators
Post by: FirebrandX on June 26, 2009, 03:13:13 PM
I spent many hours making an NTSC color NES Palette based on the composite output jack on the side of the old front-loading NES. I tested the palette against several TV displays, including an HD TV, and compared the output using the actual hardware and dozens of NES games in my collection. It's about as close I could get to what the real thing looks like, though I recall PAL users had completely different color results. This is why this palette files is strictly NTSC-based.



For those interested, you can download it here:



http://www.firebrandx.com/downloads/fbx2pal.zip


Title: RE: The color difference between NES emulators
Post by: TerraEsperZ on June 26, 2009, 07:03:51 PM
In any case, from what I've read on other forums on the subject, it's entirely possible that NES developers used whatever colors looked best on their TV and thus there might not even be a sort of "universal" palette that make each game look its best.



---

Current project: Castlevania: Aria Of Sorrow (GBA)



Upcoming project: Castlevania Legends (GB)


Title: RE: The color difference between NES emulators
Post by: DarkWolf on June 27, 2009, 09:21:52 AM
Even in this day and age people use different color settings on their monitors.  So it's not really something that will be exact anyway.


Title: RE: The color difference between NES emulators
Post by: snesmaster on June 27, 2009, 01:36:35 PM
This is kewl, I always knew there was a problem with different NES emulators using different colors, but I never knew why.  I take it the SNES uses RGB so that is not a problem?


Title: RE: The color difference between NES emulators
Post by: Maxim on June 29, 2009, 03:16:12 AM
A random look online suggests the SNES uses 5-5-5 RGB for its palettes. So there's still some scope for scaling it up to 8-8-8 in a few different ways.