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DS development > How many displayed colors, 2^15 or more?

#69486 - SeanMon - Tue Jan 31, 2006 1:29 am

Nintendo's official site of the DS's tech specs states that the DS is "Capable of displaying 260,000 colors", but the DS framebuffer sets only 16 bits (15 usable) for each pixel, for a total of 32,768 distinct colors.

260,000 is about 2^18 colors. Is the DS actually capable of displaying this many?
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#69489 - Joat - Tue Jan 31, 2006 1:46 am

According to the silkscreen on the DS motherboard PCB, there are 6 bits of intensity per channel, for a total of 2^18 displayable colors. None of the 2D hardware lets you specify better than 555 color, but it's possible the 3D hardware after alpha blending creates a 666 result, or the overall BRIGHTNESS_CR multiplies the 2D+3D 555 color and stores a 666 result.

I don't think anyone has tested which of these is true, if both of them are true, or if neither are (i.e. they're just routing a 555 video signal to 666 screens, with the LSB tied to 0 or to MSB).
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Joat
http://www.bottledlight.com

#69493 - nmain - Tue Jan 31, 2006 2:02 am

Remember that the original GBA had 5-5-5 (32k) color display but with color reproduction on the screen so poor that there were only really about ~4000 colors to work with =D.

I know 6 bit per component rgb colors were used in a number of older pc laptop tfts (maybe even newer ones), so it's very likely that the lcd hardware could support 256K colors here. For verification, depending on gamma and color reproduction, the naked eye should be able to tell the difference. This is on a PC monitor, but take a look:

http://www.oberlin.edu/student/nmain/5vs6.png

If you could get that on a ds; 5 bpp color channels on top and 6 bpp color channels on bottom, you should be able to tell that they are different, if they are...