DITHER PROCESSOR FOR COLOR IMAGE, DITHER PROCESSING METHOD FOR COLOR IMAGE, PROGRAM, AND MEDIUM

摘要

PPROBLEM TO BE SOLVED: To restrain a geometric pattern appearance due to addition of a dither pattern, when a color image data is tone-reduced by dither processing. PSOLUTION: The different dither patterns are added in respective colors of RGB to restrain the geometric pattern appearance due to addition of the dither patterns, by adding the different patterns generated in an R pattern generating means 101, a G pattern generating means 102 and a B pattern generating means 103 respectively to respective input image data by an R adder 201, a G adder 202 and a B adder 203, to subtract color respectively in an R subtractive color processing means 301, a G subtractive color processing means 302 and a B subtractive color processing means 303. PCOPYRIGHT: (C)2004,JPO