<graphics> (US "color") Colours are usually represented as RGB triples in a digital image because this corresponds most closely to the electronic signals needed to drive a CRT. Several equivalent systems ("colour models") exist, e.g. HSB. A colour image may be stored as three separate images, one for each of red, green, and blue, or each pixel may encode the colour using separate bit-fields for each colour component, or each pixel may store a logical colour number which is looked up in a hardware colour palette to find the colour to display.
Printers may use the CMYK or Pantone representations of colours as well as RGB.
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Nearby terms: Color Graphics Adapter « color model « Colossus « colour » colour depth » colour look-up table » colour model