Color Conversion
To convert from one color gamut to another is a simple procedure.
Each phosphour color can be represented by a combination of the CIE XYZ primaries,
yielding the following transformation from RGB to CIE XYZ:
The transformation 
yields the color on monitor 2 which is equivalent to a given color on monitor
1. Conversion to-and-from printer gamuts is difficult. A first approximation
is as follows:
C = 1 - R
M = 1 - G
Y = 1 - B
The fourth color, K, can be used to replace equal amounts of CMY:
K = min(C,M,Y) C' = C - K
M' = M - K
Y' = Y - K