The present invention relates to a method for coding a signal which describes a picture as a function of three tristimulus values (X, Y, Z), to produce a signal which describes the picture as a function of n independent display primaries (R, G, B, D1, . . . , Dn−3), with n>3. In this method, for each color to be represented, drive signals for the display primaries (R, G, B, D1, . . . , Dn−3) are calculated via a comparison of the location of that color with respect to a straight line in the chromaticity diagram. A number of the drive signals are mutually exclusive.
The invention also relates to a display system comprising n display primaries, where n>3.