from
The Free On-line Dictionary of Computing (8 July 2008)
true colour
<graphics> A system where the red, green, and blue components
of a colour are stored in {display memory}, as opposed to
storing {logical colours} and using a {colour palette} to
convert them to red, green, blue components.
The advantage of true colour over a palette is that it does
not restrict the range of colours which can be displayed on
screen simultaneously. For example, if eight bits are used to
store each component of each {pixel} then a total of 2^24
(about 17 million) different colours can be displayed at once
which would require a (very expensive) palette with 3 * 2^24
bytes (about 50 megabytes) of memory.
The disadvantage of true colour is that image transformations
which would normally be done by changing the palette must be
done to every pixel of the image which can be much slower.
Compare {high colour}.
(1996-03-24)