Patent ID: 7717532

Claim:
An imaging system that forms an image on a receiving medium, comprising: a fluid ejector that ejects fluid onto the receiving medium, the fluid ejector being a print head that ejects solid or phase change inks that are solid at ambient temperatures and liquid at elevated operating temperatures; a fluid ejection circuit that drives the fluid ejector; and a controller that controls the fluid ejector to eject the fluid to include a non-white and non-clear fluid or one of at least white or clear W fluid on each pixel on the receiving medium, the controller controlling the fluid ejection circuit or routine to convert a cyan (C), magenta (M), yellow (Y) and black (K) signal with pixel coverage from zero to 400 percent to a cyan, magenta and yellow signal with 100 percent coverage for all pixels, wherein the fluid ejector ejects substantially a single layer of fluid onto the receiving medium, and the controller controlling the fluid ejection circuit to perform the conversion by: substituting c, m, y for k and setting k to zero by calculating c= min(100, c+k ), m= min(100, m+k ), y= min(100, y+k ), k=0; computing cmy component by cmy=min(c, m, y); reducing c, m, and y by c=c−cmy; m=m−cmy; y=y−cmy; computing and subtracting secondary color components (my, cy, cm) from c, m and y using cm= min( c, m ), my= min( m, y ), cy= min( c, y ), c=c− ( cy+cm ), m=m− ( my+cm ), y=y− ( my+cy ), adding one third tertiary color components using c=c+cmy/ 3, m=m+cmy/ 3, y=y+cmy/ 3; adding one half of secondary color components (my, cy, cm) to c, m and y using c=c+cy/ 2+ cm/ 2, m=m+my/ 2+ cm/ 2, y=y+my/ 2+ cy/ 2; and computing white as w=100−(c+m+y).