| 摘要 |
PURPOSE:To achieve cost reduction by reducing the number of multivalent levels, that is, the number of memory bits without losing both of the image qualities of the character and pattern parts of a color manuscript, by differentiating a multivalent number of a specific color from other color. CONSTITUTION:A manuscript to be duplicated is separated into R, G and B by a color scanner 1 and the sensitivity irregularity of an image sensing element or the illumination irregularity of a light source is corrected by a shading correction circuit 2 and the deterioration of the MTF characteristic in a high frequency region is corrected by an MTF correction circuit 3. Reflectivity linearity, density linearity or the like are corrected or converted by a gamma correction circuit 4 and, in a color correction UCR processing circuit 5, the equally divided amounts of yellow, magenta and cyan toners are replaced with black toner by a color correction processing part calculating yellow, magenta and cyan amounts and an UCR processing part 5 for replacing the overlapped part of three yellow, magneta and cyan colors and Y, M, C and Bk data subjected to color correction and UCR processing are subjected to binary or multivalent processing by a gradation processing circuit 6 to be sent to a printer 7. |
