Aspect ratio in Super Nintendo games PAL vs. NTSC

[DRW]

I've got a question to you:

Today, I played "Street Fighter II" on a PAL Super Nintendo and I noticed that the game looks pretty "widescreen". I know that especially this game has black bars hardcoded into the game. But it still doesn't look right. Let me demonstrate it:

This is the select screen as a pixel perfect representation (256 x 224, black bars are part of the image generated by the Super Nintendo):


This is the same image stretched to a 4:3 aspect ratio:


And this is the image from my TV:


Notice that the rectangles with the faces look square.

While I have two CRT TVs, one PAL and one NTSC, unfortunately, I don't have an NTSC Super Nintendo, nor a PAL NES available. So, there's no way for me to compare it directly. That's why I'm asking you: What would the game look like on an NTSC TV? Vertically, would it be stretched more? Or would it look the same?

[Joe]

NTSC has ~240 active lines per field, and PAL has ~288 active lines per field. Given that they have just about the same horizontal resolution, an image with 4:3 aspect ratio in NTSC will be skewed approximately to 8:5 in PAL.

By the way, the 8:5 aspect ratio is not uncommon for widescreen computer monitors. (They call it 16:10 instead of 8:5.)

[DRW]

Interesting. I always thought that the TV stretches each image to all four sides, no matter what.

But if NTSC has 240 lines and the Super Nintendo has 224, does that mean that the games will have black borders on an American Super Nintendo and an American TV as well (even though they're smaller than on a PAL TV)?

[tepples]

Yes, there are black top and bottom borders on Super Famicom and Super NES (U) games that use 224-line mode. You can see them on a TV capture card for PC or a professional studio monitor, but a standard consumer TV will mostly cut them off. The area that occupies the 4:3 frame (as defined by Rec. 601) is actually 280 by 240 pixels, including 24 pixels of side border that TVs also cut off.

Pixel aspect ratio on the NES and Super NES is exactly 8:7 for NTSC and very close to 11:8 for PAL. Games should theoretically be (but in practice aren't) redrawn for PAL, but that's only practical for games where the 8x8 grid is unimportant, like fighting games or mode 7 racers.

Showing my work: "Overscan" on the wiki

[MaarioS]

That's because it's an NTSC game with NTSC resolution forced on PAL system. Even though you're using your PAL console, it's still the NTSC resolution (the way the game was officially programmed). PAL resolution is actually higher than NTSC (PAL height is a bit higher) so if you want to display an image in NTSC resolution, PAL just centers the screen and.... there is some space left, so the machine fills it with black color. In results you see a very nasty picture that looks just like in the photo you provided in this topic. Here you have a picture to get the idea:


ALL the games from 8/16-bit era were done that way. I know it sucks so bad but you can't do anything about it, one of the major reasons why European gaming sucked so bad :/

[DRW]

A related question: Is there any reason why the NES has a resolution of 240 lines which means PAL looks correct, but NTSC cuts it off, while the SNES has a resolution of 224 lines which means NTSC looks correct, but PAL adds black bars? Why was the NES designed in a way that its resolution is actually optimized for PAL?

ALL the games from 8/16-bit era were done that way. I know it sucks so bad but you can't do anything about it, one of the major reasons why European gaming sucked so bad :/

I guess the major reason for its suckiness is still the PAL slowdown though. The incorrect resolution is only the second worst thing.

[Joe]

A related question: Is there any reason why the NES has a resolution of 240 lines which means PAL looks correct, but NTSC cuts it off, while the SNES has a resolution of 224 lines which means NTSC looks correct, but PAL adds black bars?

Your question is invalid, because the SNES really is capable of displaying 240 lines. (...Or is it 239? I don't know very much about SNES hardware.) The number 224 gets thrown around a lot because the hardware could switch between using all 240 lines and only 224 of them, and many games chose the latter.

Why was the NES designed in a way that its resolution is actually optimized for PAL?

Was it? Only Nintendo knows for sure. I doubt PAL compatibility was even a consideration until after the PPU design was finalized. I'm not sure I'd call it "optimized" either, since it would still have some black bars at the top and bottom.

[tepples]

The Famicom PPU has 240 lines because an NTSC TV signal technically has 240 lines per field, and Nintendo was probably wanting to brag about full-screen display when competing NTSC VDPs were limited to a 192-line display with what are now thought of as huge top and bottom borders. But because of variance in overscan among 1970s TVs, whose tolerances weren't as tight as those made in the 1980s, the background planning sheets on which Nintendo designers designed FC screen layouts had markings around a 224x192 pixel rectangular safe area, outside which important information should not be drawn. Only several years into the Famicom's life cycle, when game design practices were hitting limits of video memory bandwidth from the CPU, did Nintendo decide to add a mode with a longer blanking period, which was the 224-line mode on the S-PPU.

[lidnariq]

Even 240 scanlines is still a display aspect ratio of 3:2 on PAL. (240 scanlines are not all visible on NTSC, but they would have been a DAR of 5:4)

[DRW]

224x192 pixel rectangular safe area

It find it funny: Doesn't Nintendo itself break this rule with games like "The Legend of Zelda" where Link constantly has to go to the side and bottom borders of the screen?
Also, in "Super Mario Bros.", you wouldn't even see the text at the top of the screen if you only had the center 192 pixels.

Besides, is Joe's statement that the Super Nintendo can show 240 lines correct?

[lidnariq]

Yes. There is a register that controls whether 224 or 239 [sic] scanlines are drawn.

[tepples]

224x192 pixel rectangular safe area

It find it funny: Doesn't Nintendo itself break this rule with games like "The Legend of Zelda" where Link constantly has to go to the side and bottom borders of the screen?

Has to go there but doesn't remain there long, as the screen quickly scrolls to the next screen. Caves and dungeons also have walls about 32 pixels wide, placing the hole to the next screen within safe area. But as far as I can tell, it is why Nintendo's Tetris has the NEXT window at the side instead of above the matrix as in Tengen's and Arika's versions.

Also, in "Super Mario Bros.", you wouldn't even see the text at the top of the screen if you only had the center 192 pixels.

You wouldn't see the indicators' labels, but you would see the indicators themselves (in order: score, coins, world, time), and you would see the top 8 pixels of the terrain.