METHOD AND SYSTEM FOR CONVERTING EXTERNALLY DEFINED FOUR-DIMENSIONAL COLORING AGENT INTO EQUIVALENT FOUR-DIMENSIONAL COLORING AGENT HAVING COLOR COMPONENT OF GIVEN PRINTER, AND PRINTING SYSTEM HAVING CONVERTING MEANS

摘要

PROBLEM TO BE SOLVED: To convert an externally defined four-dimensional(4D) coloring agent into an equivalent 4D coloring agent by considering the color and ability of given printer for executing a printing functions. SOLUTION: A value L*a*b* is acquired (S109) with respect to a prescribed combination of respective variable ratios for four components of externally defined CMYK. The value L*a*b* of each print patch is measured (S102), while using a spectrophotometer or any other color value measuring instrument. These values L*a*b* are correlated to correspondent CMYK values via a look-up table and an inverse transformation/interpolation program. Then, the equivalent K' at the applied printer is transformed (S104) from the applied externally defined K value (S101) by using specified techniques. The printer prints (S102) the patch of a 4th coloring agent (black) (Kp) of a series of gray scale. The transformed K' value is used (S106) for print output of the various groups of patch for (CMY(p))k'.