Patent ID: 7916349

Claim:
A method for diffusing pixel error in a halftoning process in a color management system, the method comprising: receiving an input CMYK ink coverage for each pixel in a color image; and performing, for each pixel in said color image, pixel-based adaptive processing comprising: adding an amount of ΔCMYK to said current pixel's input CMYK to generate a modified C i M i Y i K i input; dividing said modified C i M i Y i K i input into a positive dot portion C p M p Y p K p , a negative dot portion C n M n Y n K n , and an excess dot portion C e M e Y e K e and determining an amount of CMYK for each dot; transforming said determined amount of CMYK for each dot to produce a CMYKK p RGB output; hierarchically thresholding said CMYKK p RGB output to generate an output (CMYKK p RGB) h halftone for the current pixel; determining a difference between said (CMYKK p RGB) h halftone and said CMYKK p RGB output to obtain a ΔCMYKK p RGB; and transforming said ΔCMYKK p RGB to obtain an amount of ΔCMYK for the current pixel.