Blade_X_6

A Closer Look at LED Display Color Palettes

When dealing with color palettes of programmable LED displays, more is only better to a point. When it comes to color palette, a lot of ridiculous numbers are thrown around. Where else do you hear words like “quadrillion” and "quintillion" used but in the LED display industry? It's all based on the number of bits of color that can be handled by each LED diode or the total number of shades. One bit has two possible values (one or zero). Two bits has four possible values. The first being 1 or 0 and the second being 1 or 0 there are 4 total combinations that can be created for 4 shades. Jumping ahead to 8 bits, we have 256 possible combinations which create 256 shades. Keep in mind that this is 256 per color so in a full color display, we’re able to combine each of those shade levels (there are three: a red, a blue, and a green). Therefore we have (256) X (256) X (256) = 16.7 million. So an 8 bit LED display control system is capable of 16.7 million colors. A 16 bit display controller, you can imagine is capable of much more. This is the standard for most video displays and also what the Cirrus N2 is capable of. In a 16 bit system each diode is capable of 65,536 shades. When we total up all the colors we get to 281,474,976,710,656. That’s 281 quadrillion. Is that enough? Research has indicated that the human eye can distinguish between 100,000 (Calkins, David J. Mapping color perception to a physiological substrate. The Visual Neurosciences Volumes 1 and 2. The MIT Press, 1993) and 7 million (Myers, David G. Psychology. Michigan: Worth Publishers, 1995: 165.) different colors. So if we have the capability to identify a maximum of 7 million colors visually, does it really matter how many quintillion colors a display can show? This is a nonsense specification. Add to that that many major file formats such as .jpg are only 8 bits themselves (and therefore capable of only 16.7 million colors) does it matter if a display can show more than that? A display can’t show more colors than the content that’s being input. Be wary of the salesperson who's only advantage that they are able to show you is a greater number of colors. It's all just smoke and mirrors.