COLOR IMAGE PROCESSING

PURPOSE:To achieve reduction of the number of parts and decrease of cost in reproduction of a binary color halftone image by a method wherein only a binary signal is treated for inking plate generation and undercolor removal processing, an inking plate generation means is composed of only a simple AND gate or NAND gate, and an undercolor removal means is composed of only the NAND gate. CONSTITUTION:For binary input image data 101 to 103, a logical product of those three inputs is taken with an AND gate 104, and an inking plate signal 106 (K1) is outputted via a buffer gate 105. Besides, a negative logic logical product is taken with gates 110 to 112 between signals in which the three input signals 101 to 103 are inverted with invertors 107 to 109 and the output signal from the AND gate 104, and signals from which undercolors of three colors are removed, i.e. cyan 113 (c2), magenta 114 (m2), and yellow (y2) are outputted. Further, an input line is used for controlling on/off of inking plate generation and under color removal processing. When this signal is 1, the inking plate generation and undercolor removal processing are performed. When this signal is zero, the inking plate generation and undercolor removal processing are not performed.