Method of matching hardcopy colors to video display colors in which unreachable video display colors are converted into reachable hardcopy colors in a mixture-single-white (MSW) color space

摘要

A method for matching hardcopy colors to display colors for registered-dot ink-jet copiers. Video RGB (red-green-blue) is converted into chromaticity coordinates in XYZ color space. An explicit solution is achieved by defining a new MSW color space which restricts the hardcopy colors to some percentage of one of the binary mixtures (M) of inks, some percentage of one of the single (S) inks, and some percentage of paper white (W). The color data in XYZ space is converted to MSW space and unreachable display colors are mapped into reachable hardcopy colors. Correction for hardcopy non-linearities is accomplished by using coverage ratios to correct for color shifts due to interaction among the inks. The MSW values are then converted to CMY (cyan-magenta-yellow) values which are processed in accordance with an appropriate dithering algorithm for conversion into dots for printing on paper.