< 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.
(1999-08-02)