| 摘要 |
PURPOSE:To realize always excellent copying of a picture even when the density characteristic is subject to change due to a difference of a structure between machines or an external environmental change by correcting properly the complicated reproduction density characteristic of the picture copying machine. CONSTITUTION:A CPU 112 allows a pattern generator 113 to generate a color patch based on pattern signals Yo, Mo, Co, BKo decided in advance for each of Y, M, C, Bk and a print processing section 111 prints out the patch. Feedback signals Y, M, C, Bk are obtained by applying color separation, shading correction, logarithmic transformation and masking processing similar to the picture output processing to the gradation pattern patch. The feedback signal is stored in a memory 114. The color correction is implemented so that a pattern signal and the feedback signal of a color original are identical to each other. |
