Patent ID: 6885380

Claim:
A method for transforming three color input signals (R, G, B) corresponding to three gamut defining color primaries to four color output signals (R′, G′, B′, W) corresponding to the gamut defining color primaries and one additional color primary W for driving a display having emitters that emit light corresponding to the four color output signals, comprising: a) calculating a common signal value S as a function F 1 of the three color input signals (R,G,B) for a current and neighboring pixels; b) determining a final common signal value S′ based upon the common signal for the current and neighboring pixels; c) calculating the three color signals (R′,G′,B′) by calculating a value of a function F 2 of the final common signal value S′ and adding it to each of the three color input signals (R,G,B); and d) calculating the output signal W as a function F 3 of the final common signal value S′.