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Questions about video and sound on Nestopia and on real NES/Famicom hardware

I've recently begun to get into NES/Famicom emulation, and I have a bunch of questions that I haven't found clear answers to, so I created this thread with the intention of finding some of these answers, and to help others who have similar questions to find answers for themselves.

VIDEO

Color Palette -- Every emulator I have tried so far has rendered games with different colors. Furthermore, there are people out there who are striving to make the perfect color palette (like AspiringSquire -> Link 1 Link 2). Doesn't the NES/Famicom, when rendering an image, render a pixel with an exact color? Why don't emulators just look to that for the correct color palette?

Aspect Ratio -- The TV Aspect option doesn't work exactly right in Nestopia. This can be tested with either Kirby's Adventure (the circle drawn in the game's opening) or tvpassfail. To clarify, it does work properly for 1X and 2X screen sizes, but not 3X, 4X, Max, or Fullscreen for any resolution over 640 x 480 (but I'm not sure if it works for resolutions lower than 640 x 480). Does anyone know if this option will be fixed?

SOUND

Sound Effect (specific instance) -- So far, my video questions are much more pressing. Regardless, I've noticed that the sound effect for throwing fireballs in Super Mario Bros. is off in Nestopia, but sounds correct in FCE Ultra. I find it hard to believe this problem could have gone unnoticed for such a popular game, so what am I doing wrong? My sound settings are all at their defaults.

--------------------

If any other questions pop up, I'll add them here. I'll also throw any answers I get up here for people to see.

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The NES directly generates an NTSC signal, it is never in an "RGB" form. However, Nestopia has something better than any palette can do! A couple years ago, an NTSC emulator was developed by a guy named Blargg, which can quite accurately reproduce NES video.

To enable, go into the video options and for the "Filter" item, select NTSC.

For filter settings, I use:
Field Merging - Auto
Scanlines - 50
Tuning - Auto
TV-Aspect - checked
Bilinear Interpolation - unchecked

Some of my other video settings:
32-bit color
Memory Pool - Video (this basically does free bilinear interpolation)
Palette - Auto
Monitor Frequency - Auto

I'm not sure if this is neccesary, but if NTSC filter behaves strangely for you (like odd flickering), set your monitor refresh rate to 60Hz

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I've tried that, but I thought it wasn't what I was looking for.

Although, you're saying the image the NES/Famicom renders looks like that from the very start (NTSC filter), even before the signal leaves the PPU? This makes me wonder how the Wii Virtual Console emulates the NES/Famicom, because it surely doesn't look like that (NTSC filter), and I'd assume Nintendo's in-house emulator for their own system would probably be the most accurate.

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No. He's saying the NES/Famicom generates NTSC video, and when processed through a television it will look just like what Blargg's NTSC emulator does. If you use the Wii with a composite cable, it's similar (but not identical) to what a real NES would also output over composite, but in both cases it's the distortions caused by an NTSC TV that do the "magic". (This is also why Virtual Console looks like complete ass if you use an HD component cable on the Wii like I do).

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I like the look of Virtual Console over component video. It gives a very crisp picture, and I believe that's similar to what I'm looking for from an NES/Famicom emulator -- I want the color accuracy of the image the actual NES/Famicom hardware renders, but without the NTSC artifacts. Basically, I want clear and defined pixels, along with the exact colors that the NES generates images at.

Now, a couple of more questions:

1) Although the NES/Famicom generates NTSC video, don't most consoles (especially after the NES/Famicom) generate video in an RGB format?

2) Can anyone explain how the Sharp Famicom Titler works? It outputs Famicom games over S-Video... How does it do this? Does it render games the same way a normal NES/Famicom does, then convert the YUC signal to a Y/C signal for S-Video output? Or does it do something else? Or am I misunderstanding something?

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Here's your problem: the exact colors generated by an NES/Famicom *are* NTSC artifacts. Virtual Console over component is exactly what NES games are NOT supposed to look like, but if you just turn off all the filters you'll get something similar in NEStopia. The artists for NES (and SNES and Genesis) games drew the graphics to look good *with* NTSC artifacts. In that way they could achieve colors and blending effects that weren't actual hardware features until much later consoles.

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And so that's why people are striving to create the best palette? They want to get the image as close as possible to the actual colors of an NES/Famicom without having all the NTSC artifacts?

I've only really looked into NES emulation, but if I'm understanding this correctly, then the same isn't necessarily true for SNES emulation, right? The SNES supports RGB output, and renders games in RGB format, so there is no quest for a correct palette, right?

All that said, exactly how does the Virtual Console achieve its NES emulation? What kind of a palette does it use? And of the available palettes for NES emulators, which is the closest to true NES colors (YUV in Nestopia? Something else?)?

Unfortunately, I don't have a working NES right now to compare the actual output to an emulator palette, but if I did, how would I best go about that?

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Yeah the SNES uses RGB internally, as do most other later consoles AFAIK.

No NES palette will give you the best colors in every case. Before NTSC emulation, I too was trying to create an accurate as possible palette, and you just run yourself in circles. You tweak it for one game, and that makes another game worse.

If you don't like the gritty NTSC look, you could also try going into the NTSC filter settings and turn Auto-Tuning off and then hit the "RGB" preset button.

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I took your advice and tried checking the Auto option in Tuning to off for the NTSC filter and switching to the RGB preset in the NTSC filter settings, but as far as I can tell, all that does is produce the same picture as the Standard filter, just with a slight blur. The blur isn't as bad as having bilinear interpolation checked to on for the Standard filter, though.

I tried to use the color palette for the NES found on Wikipedia (scroll down), but it looked incorrect, like it was too red or orange, at least on the Super Mario Bros. title screen.

Also, in Nestopia, where do the YUV and RGB Palettes come from that come default with the emulator? Who created them and what did they base them on?

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If I had to guess, the built-in YUV and RGB palettes were also based off the NTSC filter. That's probably why the picture using NTSC RGB preset looks the same as the standard filter. You'd probably get a blurring effect if your using video memory, if that's the case, try switching it to system memory and that should fix it.

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Oh my, so much nonsense in one thread.

Originally Posted By "BootGod"
an NTSC emulator was developed by a guy named Blargg
It was developed by me, then optimized for speed and distributed without my explicit permission by Blargg, and obviously without credit, not that anyone cares.
Originally Posted By "R. Belmont"
Here's your problem: the exact colors generated by an NES/Famicom *are* NTSC artifacts. (..) The artists for NES (and SNES and Genesis) games drew the graphics to look good *with* NTSC artifacts.
That's a bunch of crap. The NES does NOT primarily work on "artifact color". The Apple II and CGA with some games do, but NOT the NES. There are THREE (3) differences between a "NTSC-filtered" and an RGB picture made from a "palette":

1. Chroma subresolution: the color has a lower resolution than the brightness. This is ONLY relevant on one- or two-pixel-wide colored areas, where transitory colors appear. This effect also happens with S-Video.
2. Cross-color artifacts: some of the luminance information is incorrectly interpreted as color, causing "rainbow swirls". What this artifact color looks like depends on the phase of the chroma subcarrier relative to the pixel clock, which is not only changing from pixel to pixel, but also UNDEFINED on power-up. On the Famicom, I can reset a game, and the cross-color artifacts on the title screen, are sometimes the opposite from before resetting. You don't see that on the U.S. NES because the reset button also resets the PPU. But obviously, this makes it impossible to use this kind of artifact by an artist for effect.
3.- Cross-luma artifacts: some of the chrominance information is incorrectly interpreted as brightness, causing "jaggy edges". I know of no game that uses this to any effect, for the same reason as 2.

2. and 3. only appear with composite video, not S-Video. Only 1. is used for effect on *some* games, and is annoying on many others. SMB1 and others scroll at a fractional pixel speed to avoid 3. becoming too visible, but 2. and 3. are impossible to be used for effect.

In other words: A "palette" will be sufficient for any game that does not heavily rely on chroma subsampling, which by my count are most games. The "Composite/S-Video" setting buttons in NEStopia are nonsensical, as "Composite" looks more like RF, and S-Video looks like a well-comb-filtered RF signal. I can't tell you why that is, because I have no clue what picture processing operations lie behind phenomenological terms such as "Sharpness" and "Resolution".

And whether you use a NTSC filter or a palette does NOT answer the question of how greenish or brownish color x8 should look, or how blueish or purplish color x3 should look. That depends on the TV set that the graphics artist/programmers used; precisely speaking, the result is precisely defined by the TV's:

1. signal amplification and clamping. Some TVs use the color burst as an amplitude reference, others don't.
2. chroma decoding angles and gains
3. phosphor chromaticities and white point.

All these can be precisely emulated if you know the values. NEStopia by default assumes standard NTSC chroma decoding angles and gains, which no real non-studio TV set uses. It allows for user-adjument of these settings, but those are worthless without simultaneous emulation of different phosphor chromaticities and white point, also known as "Color Management".

Unless you want to Turing-successfully emulate the look of a particular TV set, the best solution is to just use an idealized PALETTE designed to make COMBINATIONS of colors look sensible, and activate chroma subsampling only on those games that use it for effect. There's no good reason to emulate actual chross-color/-luma artifacts, and YUV-derived *color values* don't get you anything useful that a palette can't, unless you care about having a "Hue" and "Saturation" slider to play with.

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I can assure you that every piece of art for 8 and 16-bit games was hand-tuned using NTSC televisions and composite monitors. Even if the artifacts weren't used specifically for effect, they did influence things like color choice and thus with the artifacts is the way the games were intended to be seen. Period. (This is also why PAL ports were so half-assed most of the time).

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Sounds like someone's all pissed because he didn't get any credit and is now trying to discredit the usefulness of it because of that.

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Quote:
I can assure you (...) Period.
Well, I doubted you before, but NOW I am convinced. :P

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(This is also why PAL ports were so half-assed most of the time).
Which PAL "ports" are "half-assed" and what does this have to do with artifacts? I find PAL versions to be identical to NTSC versions, except that the picture is letterboxed and they play slower.

Quote:
Sounds like someone's all pissed because he didn't get any credit and is now trying to discredit the usefulness of it because of that.
Sounds like you couldn't be bothered to read and understand the full post and are now trying to churn out a smartass remark.

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the picture is letterboxed and they play slower.


Exactly. Native PAL games were not letterboxed and played the right speed.

Anyway, if you're so down on NTSC, why did you create the filter? It certainly looks pretty sour-grapey.

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Native PAL games were not letterboxed and played the right speed.
But what does this have to do with artifacts and color choice? That's the context in which you brought it up, which is why I ask for clarification.

Creators may have avoided particular color combinations because of artifacting as you claim, but that doesn't make a lack of artifacts look worse. Speculating about what is "intended" amounts to palm reading, because you can't know what the creators intended, or how much artifacting their particular TV set had.

There are two possible goals for emulator authors:
1. increasing game enjoyment, and
2. 100% accurately looking like a particular TV set.

For game enjoyment, you want a clear picture with nice colors. "Nice colors" requires a palette that makes color combinations, such as light brown (0x27) and bright brownish-red (0x36), look proper. For some games, you also want chroma subsampling for transitory colors. But you don't want nasty edges or rainbow swirls around objects.

To 100% emulate a particular TV set's look on the other hand, the critera are different. You need all the extra things I talked about, in addition to NTSC artifacting and filtering. It's an interesting challenge, but not neccessarily good for game enjoyment, as there are some nasty-looking TV sets out there. smile
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Anyway, if you're so down on NTSC, why did you create the filter?
For Apple II and CGA, which you should know.
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It certainly looks pretty sour-grapey.
That's MooglyGuy's incorrect contention. I bother writing ~40 lines of post not to descredit but to inform.

NEStopia brings RF quality to "composite" and "RF" settings, and lacks proper Color Management to make adjustable YUV decoding angles/gains meaningful. It also gives people the false impression that using an NTSC filter makes for more accurate colors than palettes, as evidenced in one of MooglyGuy's posts some time ago, when actually except for the chroma subsampling for small-area colors, one has nothing to do with the other.

All these are legitimate points, so stop the psychobabble please, if you could be so kind.

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My point about PAL was simply that NTSC was so ingrained in the design process (at least in the US) that a) it hurt ports to other systems and b) clinically clean RGB output is not how the games were designed, so on some level it's not right.

Emulators are at least in part about nostalgia. I don't get that feeling from perfect sharp pixels. I need the fringed text, the dot crawl, the smearing on scrolling dither patterns, and the bleeding reds. That's what it actually looked like on real hardware (in the 80s, I played NES on a good quality 1985 model GE TV so it had a decent comb filter and so on). You can easily prove that no possible settings are "perfect", and it doesn't matter. The defaults in NEStopia with the NTSC filter compare quite favorably to real-world hardware, even if they're provably not exactly right.

Feel free to make your own emulator that's perfect by your standards (with color management and whatnot), and I'll probably switch to it when it comes out (assuming I can build it on Linux). Or make your own filter and Marty will probably add it. Either way, everyone wins.

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Well, look at that. I can't edit my first post. I'll just have to post some answers to my original questions here.

By the way, the discussion in this thread got too technical for me, so I'm just going to try to keep this basic.

Originally Posted By Josh7289
Questions about video and sound on Nestopia and on real NES/Famicom hardware

I've recently begun to get into NES/Famicom emulation, and I have a bunch of questions that I haven't found clear answers to, so I created this thread with the intention of finding some of these answers, and to help others who have similar questions to find answers for themselves.

VIDEO

Color Palette -- Every emulator I have tried so far has rendered games with different colors. Furthermore, there are people out there who are striving to make the perfect color palette (like AspiringSquire -> Link 1 Link 2). Doesn't the NES/Famicom, when rendering an image, render a pixel with an exact color? Why don't emulators just look to that for the correct color palette?

The NES/Famicom only renders video in the NTSC colorspace -- not in RGB. What this means is that there is no possible way to get the colors of NES/Famicom games on an RGB emulator/platform/monitor (like a PC) the exact same as they are on actual hardware. It just has to do with the inherent differences between the NTSC colorspace and the RGB colorspace.

Quote:
Aspect Ratio -- The TV Aspect option doesn't work exactly right in Nestopia. This can be tested with either Kirby's Adventure (the circle drawn in the game's opening) or tvpassfail. To clarify, it does work properly for 1X and 2X screen sizes, but not 3X, 4X, Max, or Fullscreen for any resolution over 640 x 480 (but I'm not sure if it works for resolutions lower than 640 x 480). Does anyone know if this option will be fixed?

This is still an issue.

Quote:
SOUND

Sound Effect (specific instance) -- So far, my video questions are much more pressing. Regardless, I've noticed that the sound effect for throwing fireballs in Super Mario Bros. is off in Nestopia, but sounds correct in FCE Ultra. I find it hard to believe this problem could have gone unnoticed for such a popular game, so what am I doing wrong? My sound settings are all at their defaults.

It turns out Nestopia is the correct one. The fireball sound effect is still "off" most of the time, but I recently played the game on actual hardware, and I heard the same thing as I heard in Nestopia. FCE Ultra wasn't emulating the hardware as accurately as Nestopia, it seems.

Quote:
--------------------

If any other questions pop up, I'll add them here. I'll also throw any answers I get up here for people to see.

I have come up with one other question:

VIDEO

Actual NES/Famicom hardware can be modded to have RGB color rendering and output with any of the following PPUs:

-- Any of the Rx2C03x PPUs (available from Vs. Tennis, Vs. Duck Hunt, Vs. Ice Climber (JP), PlayChoice-10, and the Sharp C1 Television)

-- And the RC2C05-99 PPU (available from the Sharp Famicom Titler)

Because these are RGB PPUs, the colors are not the exact same as the regular PPUs of actual NES/Famicom hardware. However, in all Nintendo promotional material, screenshots of games were always taken with these RGB colors, making the color palette on these PPUs (which is the same between all of them) the "official" NES/Famicom RGB color palette.

My question is: Has anyone exactly replicated this color palette in an emulator? Alternatively, does anyone know where I can find exactly which colors are in this "official" palette so I can make a custom palette to use in an emulator myself?

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Quote:
Because these are RGB PPUs, the colors are not the exact same as the regular PPUs of actual NES/Famicom hardware. However, in all Nintendo promotional material, screenshots of games were always taken with these RGB colors, making the color palette on these PPUs (which is the same between all of them) the "official" NES/Famicom RGB color palette.


The RGB PPU's palette is not "official" in any way. First, several Playchoice 10 games (Punch-Out, Volleyball) actually select different colors to look better on the RGB PPU. If the RGB PPU were the official palette, there would not be a difference in the colors that the regular NES version uses (for NTSC output) versus the PC10 version.

Second: yes, the American "Nintendo Power" and the German "Club Nintendo" since 1990 used the RGB PPU to take screenshots, but those screenshots were then "corrected". For example, Metroid's Brinstar stage looks very greenish in the RGB PPU's palette, but was made to look bluer in most screenshots, because that's what the NTSC PPU outputs. They forgot to do that in a few pictures however, revealing the original rather ugly RGB PPU's palette.

Also, in Japanese television commercials, the game display is almost always visibily filmed off a composite TV.

There is no "official" palette, because every developer just chose the colors to look good on his TV, and there was a lot of variation in NTSC televisions in the 1980s, more than now. There just is not one palette OR setting for the NTSC filter that will make all games look right.

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Has anyone exactly replicated this color palette in an emulator?


Yes. Select "RGB" in Nestopia, that IS the RGB PPU's palette. smile

Beware though that it is designed for a monitor with a 9300K color temperature, so select that setting on your monitor if you can, otherwise the reds and browns will jump in your face.

If it then still looks different from that promotional shot you saw keep in mind what I told you about them being retouched.

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For games developed in the US, *the* developer monitor for NTSC-output games (including PS1/N64/Saturn) was the Commodore 1084/1084S and/or the Phillips equivalent, with the controls all set to the detents. So if you can find schematics for one, you can have a "what the developer saw" setting. (I would imagine for European-developed PAL games the PAL version of the 1084 was also popular, but I can't prove it).

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http://www.acc.umu.se/~patrikax/amiga/others/schematics/1084.zip

Get going wink

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First of all, I have to clear up what I was looking for. I didn't want a "correct" palette, or what the developer saw, or what the developer may have intended. I just wanted a palette that exactly mimicked the NES-compatible RGB PPUs, no matter how incorrect those may have been for games compared to the NES' NTSC PPU.

Originally Posted By NewRisingSun
Quote:
Has anyone exactly replicated this color palette in an emulator?


Yes. Select "RGB" in Nestopia, that IS the RGB PPU's palette. smile

Beware though that it is designed for a monitor with a 9300K color temperature, so select that setting on your monitor if you can, otherwise the reds and browns will jump in your face.

If it then still looks different from that promotional shot you saw keep in mind what I told you about them being retouched.

So I guess this is what I was looking for. I wasn't sure if Nestopia's RGB palette was correct, though, since the browns were way too red, as you noted. But (according to you wink ), it is the exact palette that I'd find on the RC2C05-99 PPU or any of the Rx2C03x PPUs.

Also, you say I should set my monitor to a color temperature of 9300K. Is that because of Nestopia's implementation of the RGB palette, or is that something inherent in the RGB PPU itself?

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Neither. Because we haven't yet invented perfect invincible electronics, even PC monitors vary in terms of what colors they'll display given a particular input signal. That doesn't matter for email or Clippy or even Vista Aero, but it's huge for people doing professional image work (photo or video editing). If your monitor is at a known color temperature than you can certify that RGB values X/Y/Z will match Pantone color A or whatever.

In this case, if your monitor is set and calibrated to 9300K the Nestopia RGB palette will exactly match the nominal output from the RGB PPU on an arcade RGB monitor. It's really that simple.

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For games developed in the US, *the* developer monitor for NTSC-output games (including PS1/N64/Saturn) was the Commodore 1084/1084S and/or the Phillips equivalent, with the controls all set to the detents.
For NES games too? Do you have that on good authority? I find that hard to believe.

Quote:
Also, you say I should set my monitor to a color temperature of 9300K. Is that because of Nestopia's implementation of the RGB palette, or is that something inherent in the RGB PPU itself?
The RGB PPU. It assumes a white point near 9300K in the display monitor.

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In this case, if your monitor is set and calibrated to 9300K the Nestopia RGB palette will exactly match the nominal output from the RGB PPU on an arcade RGB monitor.
Only if the red/green/blue primaries are the same as well. And the gamma. And there are several white points commonly described as "9300K". Sorry, it's not THAT simple. smile

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I have it on good authority from friends for the NES era, and I personally programmed several dozen commercial games on those things for 16+ bit systems. There were no decent consumer TVs under 20" with composite inputs until the mid-90s, and fitting everything in an average cubicle was an issue. The Commies were relatively cheap, reliable, and compact. And they had one final trick up their sleeves for the PS2 era: you could turn the vertical height down far enough to get real anamorphic 16:9 once that became a feature in games.

And Don Quixote here will only settle for exact RGBPPU colors for some deranged reason, so if that's the case just link the En Vogue video ("never gonna get it") and I'll lock the thread :-)

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Originally Posted By R. Belmont
And Don Quixote here will only settle for exact RGBPPU colors for some deranged reason, so if that's the case just link the En Vogue video ("never gonna get it") and I'll lock the thread :-)

-_-

I just like screwing around with things, so I wanted to see what the games would look like with the RGB PPU!

Also, I understand that it would take quite a bit of effort to get a monitor's settings to display the exact colors that the RGB PPU is generating, if it's even possible at all for any particular monitor. That's not my real concern, though...I mean, when it comes to the emulator's color palette, I just want the emulator to generate the exact colors. As far as what my monitor does to those colors, that's an entirely different issue.

So for anyone that still wants to put up with me, what's it like for the SNES PPU, which is natively and normally RGB? I mean, is the SNES PPU also designed for a color temperature of 9300K on the monitor side, among other things?

P.S. So what's up with the color palettes that come default on other NES emulators? If none of them are the "true" RGB palette, and none of them are made to look close to the NTSC PPU, are they just random colors the emulator designers decided might look good??

Last edited by Josh7289; 04/03/08 05:01 PM. Reason: I edited this post while you were replying to it, R. Belmont...So if you want to answer my other questions, go right ahead. :P
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For all intents and purposes natively-RGB programmable-palette PPUs like the SNES are the same as a PC video card with an NTSC encoder slapped on the back end. Of course, that wasn't literally true until the original Xbox ;-)

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Originally Posted By R. Belmont
I have it on good authority from friends for the NES era,
Aha. Because looking at the schematics and the ICs used, that monitor would have by-the-book NTSC decoding, and if you also have the Hue knob at the detent position, you'll get very greenish yellows on the NES. It's because most NES games assume color #8 is yellow. However, color #8 is not actually yellow, it's 180 degrees phase, whereas true yellow is at 165 degrees phase, so it's greener than it should be. Which is why I would assume that either most didn't use that monitor after all, or they at least turned the hue knob minus 15 degrees.

Originally Posted By Josh7289
I just like screwing around with things, so I wanted to see what the games would look like with the RGB PPU!
Well, now you know. It's not a pretty sight, in my opinion. Theoretically, I could take the raw RGB PPU values and convert them to display properly on an sRGB display.

Originally Posted By Josh7289
I mean, is the SNES PPU also designed for a color temperature of 9300K on the monitor side, among other things?
I should clear things up a bit I guess.

The RGB NES PPU outputs hard-wired RGB voltages from values chosen by the chip designer. The SNES PPU outputs software-set RGB voltages from values chosen by the software developer.

RGB values are always *relative* to a color space, or color profile, defined by a monitor's red/green/blue/white primary chromaticities and gamma. The "correct" profile is whatever the designer/developer's monitor had, he chose the RGB values to look good on his monitor.

The NTSC broadcast system defines a particular color profile for North America, and different one for Japan. However, that only applies to broadcast video, there's no guarantee that a video game developer actually used a monitor of those specifications, because broadcast-quality "Grade 1" monitors are VERY expensive.

In reality, unless we ask the developer what monitor he used, it's only conjecture. However, a *rule of thumb* is that if a picture's reds and browns are too bright on sRGB with the 6500K white point, it's *probably* designed for 9300K. This certainly applies to the RGB PPU palette, as well as the old Nesticle one. On the other hand, we know that most monitors from the MS-DOS era had a 9300K white point, so most DOS games on sRGB look (slightly) wrong, not that most people notice.

While most standards, including sRGB, NTSC and PAL call for a 6500K white point, monitor makers liked and like the 9300K one because it 1) seems "brighter" to most people, and 2) it looks good even when the surrounding light comes from a fluorescent lamp. 6500K is the color of daylight and looks kind of reddish when the surrounding light comes from a fluorescent lamp.

Unfortunately, the schematics don't tell us what color chromaticities the 1084 has. smile

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I don't think the following question was answered yet, since I'm still wondering about it, so here it is again:

Where did the YUV color palette in Nestopia come from? Who made it? How did they go about choosing which colors to use, in order to approximate an actual NES RP2C02 PPU's output (as I assume that's what this YUV color palette was designed to approximate)?

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Last edited by R. Belmont; 08/09/08 12:13 PM.
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I have an idea of what you're trying to say, but I'd still appreciate it if you could make a link between those two Wikipedia pages and Nestopia for me. >.>

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Why do you care so much? It's not an approximation: the PPU is a digital device so NEStopia (and most other decent emulators now) can use the mathematics in those articles to generate the same exact phase angles (and therefore colors) that the PPU outputs. It happens that MAME figured out that math first, but nobody ever gives *them* credit for anything smile

NewRisingSun will now show up and say that matching the PPU output is pointless because the actual colors come from your television and where your little brother set the "tint" control, but what NEStopia displays is a very good match for a wide variety of mid to late 80s NTSC televisions.

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Originally Posted By Josh7289
I have an idea of what you're trying to say, but I'd still appreciate it if you could make a link between those two Wikipedia pages and Nestopia for me. >.>


Originally Posted By R. Belmont
Why do you care so much?


Has anyone but me ever noticed a link between people who care an inordinate amount about the inconsequential minutiae of a given emulator and people who use "anime" smileys (>.>, ^_^, and so on)?

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Originally Posted By R. Belmont
Why do you care so much?

Hm...Well, I just do. Is that good enough? smile

Originally Posted By R. Belmont
It's not an approximation: the PPU is a digital device so NEStopia (and most other decent emulators now) can use the mathematics in those articles to generate the same exact phase angles (and therefore colors) that the PPU outputs. It happens that MAME figured out that math first, but nobody ever gives *them* credit for anything smile

Ah, that's really cool. Two questions, though. You mentioned "most other decent emulators"; were you referring to other NES emulators in particular, or emulators of any system that don't render colors in RGB in general? And...When did the MAME people first figure all this out? It's really pretty cool...

Originally Posted By R. Belmont
NewRisingSun will now show up and say that matching the PPU output is pointless because the actual colors come from your television and where your little brother set the "tint" control, but what NEStopia displays is a very good match for a wide variety of mid to late 80s NTSC televisions.

Well, I would disagree with him. I'd say the "actual colors" are what the RP2C02 PPU is directly generating. Regardless of what my TV does with those colors, the colors the PPU produces are fixed. If I want to change which colors I ultimately see, I can just adjust my monitor settings (in the same way that I could adjust the settings on my TV connected to my real NES to ultimately change which colors I see).

Did that make sense?

Originally Posted By MooglyGuy
Originally Posted By Josh7289
I have an idea of what you're trying to say, but I'd still appreciate it if you could make a link between those two Wikipedia pages and Nestopia for me. >.>


Originally Posted By R. Belmont
Why do you care so much?


Has anyone but me ever noticed a link between people who care an inordinate amount about the inconsequential minutiae of a given emulator and people who use "anime" smileys (>.>, ^_^, and so on)?

...If it makes a difference, I only started using >.> a few months ago, when I noticed one of my friends doing it. I guess I used to use O.o;; or something similar before I started using >.> .....

And I wouldn't call this "inconsequential minutiae". If the developers of the emulator care enough to know this stuff, then what's so different about me caring to know that same information?

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I believe in particular that Nintendulator generates it's palette the same way. I don't remember who or when the idea of doing the palette from the NTSC math first came up. Pretty much all Apple II emulators generate colors the same way, in part because of how Woz bent the NTSC spec to do his bidding for cheap smile

Oh, and byuu uses anime smilies too and he's the lord and master of caring too much about console details (it's just he codes them all into bsnes instead).

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Originally Posted By "Josh7289"
Well, I would disagree with him. I'd say the "actual colors" are what the RP2C02 PPU is directly generating. Regardless of what my TV does with those colors, the colors the PPU produces are fixed.

The problem is that the only definition of what color it was generating was what TVs and video displays of the time displayed. Apparently the way NTSC color is decoded has changed subtly over the years, so there's no real definition of what color a particular signal should give, hence the backronym Never The Same Color. The PPU's color carrier is also a square-wave instead of a sinusoid, so it's partly up to the TV on how to handle the higher harmonics.

Originally Posted By "Josh7289"
If I want to change which colors I ultimately see, I can just adjust my monitor settings (in the same way that I could adjust the settings on my TV connected to my real NES to ultimately change which colors I see).

Computer displays rarely have tint, color saturation, and sharpness controls. smile

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Originally Posted By "Josh7289"
Aspect Ratio -- The TV Aspect option doesn't work exactly right in Nestopia. This can be tested with either Kirby's Adventure (the circle drawn in the game's opening) or tvpassfail. To clarify, it does work properly for 1X and 2X screen sizes, but not 3X, 4X, Max, or Fullscreen for any resolution over 640 x 480 (but I'm not sure if it works for resolutions lower than 640 x 480). Does anyone know if this option will be fixed?

I've been also concerened about this for some time, but my observings are quite different. AR for NTSC filter is wider than any other filters, good game to test it is Ultimate Stuntman. When in NTSC with TV Aspect, the opening Camerica's logo is nicely circular, but the smaller logo which is presented later (after a few seconds wait) is a bit too wide. When in Standard with TV Aspect, opening logo is not enough wide, but the latter is ok. I didn't notice any different behaviour when in other scaling modes (I'm using Max). So, the results bring some confusion even after reading this topic http://nesdev.parodius.com/bbs/viewtopic.php?t=3393&postdays=0&postorder=asc&start=0 and NewRisingSun's calculations. My question is why NTSC filter has wider scaling and which is correct?

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Graphics weren't always drawn to the correct aspect ratio in these games, so inconsistencies within a game are pretty much expected. Game graphics were drawn on PC monitors and artists largely had to eyeball the aspect ratio (especially at smaller studios). In this case the Camerica logo was likely drawn by a more experienced artist because of it's relative legal importance.

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Well, I tested Nestopia on my laptop and clearly there is something wrong. On 1280x800, Standard Filter (with TV Aspect and Max) produces, I assume correct image (after all this confusion hell knows), but NTSC Filter at the same settings produces image which ratio resembles 1:1. On 640x480, NTSC Filter (with TV Aspect and Max) produces wider image than Standard Filter with TV Aspect and Max (mentioned in my previous post). Another thing is that sometimes when switching between Standard and NTSC you can have other ratios than 1x and Max for NTSC with TV Aspect, but not always (it has to do with TV Aspect option in NTSC Filter Options and Emu). What is the correct Aspect Ratio for NTSC NES and how to make it in Nestopia?

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Originally Posted By diminish
Well, I tested Nestopia on my laptop and clearly there is something wrong. On 1280x800 Standard Filter with TV Aspect and Max produces, I assume correct (after all this confusion hell knows), but NTSC Filter at the same settings looks like 1:1. On 640x480 NTSC Filter with TV Aspect and Max produces wider image than Standard Filter with TV Aspect and Max (mentioned in my previous post). Another thing is sometimes when switching between Standard and NTSC you can have other ratios than 1x and Max for NTSC, but not always (it has to do with TV Aspect option in NTSC Filter Options and the same in Emu). What is the correct Aspect Ratio for NTSC NES and how to make it in Nestopia?


Can you please rephrase your post? It's very difficult to understand.

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Uh oh, sry for the lousy previous one, I'll try to explain things in more detail:

1280x800 Standard Filter, TV Aspect, Max scaling - presumably ok Aspect Ratio;
1280x800 NTSC Filter, TV Aspect, Max scaling - probably 1:1 (looks like);
640x480 NTSC Filter, TV Aspect, Max scaling - wider than 640x480 Standard Filter, TV Aspect, Max but not totally streched to 4:3;

Also in 1280x800, when unchecking TV Aspect in NTSC and menus and having Standard Filter On before, results in having 2x and 3x scaling ratios additionally with NTSC, which aren't working when you again check TV Aspect in menus (because normally in that mode there is only 1x and Max), but it's really a minor. Ideally, when you would check back TV Aspect in menus it should hide 2x and 3x or just work with these.

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Quote:
It happens that MAME figured out that math first
When? Where? Why did the arcade emulator team care about the home console's video output?

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MAME and MESS have always shared PPU code, and way back in prehistory (circa 1999 I think) it used the phase angle palette generation for PC10 and Vs as well. The original implementation turned out to be not exactly right a few years later, but the actual math was of course sound.

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Originally Posted By R. Belmont
It happens that MAME figured out that math first, but nobody ever gives *them* credit for anything smile

MAME code cannot be reused in Nestopia, so they really don't deserve credit...

Not trying to start a license war, but it's just a fact that the MESS/MAME licenses make it difficult or impossible to reuse parts in other software.

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That's an amazing misinterpretation of my statement just to get in a license flame, of all things.

Maybe I'm weird, but I credit people for ideas when I'm writing code, even if I don't implement it the way they suggested.

PS: most devs are agreeable to dual or triple licensing. It's usually a good idea to actually ask before you assume the license is preventing you from doing something.

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Fair enough. And maybe I'm weird (actually I've got hard proof of it :P), but I don't really think it's necessary to credit everyone else that's done an idea before me. For example, if I ever write a unix-like kernel, I wouldn't feel it necessary or even desirable to credit Andrew Tannenbaum, Linus Torvalds, and Theo de Raddt just because they all have worked on Unix-like kernels.

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Quote:
it used the phase angle palette generation for PC10 and Vs as well. The original implementation turned out to be not exactly right a few years later, but the actual math was of course sound.
But that code was copied from Kevin Horton's QBASIC implementation, so it's not like they came up with it. Hence my question.

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Oh, I see. So you knew all along, but you couldn't resist the opportunity to play "gotcha" instead of just clearing things up. Carry on.

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