Color image processing apparatus with image corrector

摘要

A color copying machine has a scanning-type proximity linear image sensor unit for optically scanning an input image and producing an image read signal, and a color printer unit for producing a copy image corresponding to the input image at limited levels of printing density. An image type discrimination circuit receives the image read signal, and at least partially discriminates the type of image based on a pattern matching technique, thereby producing a discrimination signal for specifying the image type in a pixel region of a predetermined size of the input image. An adaptive signal processing circuit also receives the image read signal, and performs different image signal correction processing in accordance with the discriminated image type, thus producing a corrected image signal, which is supplied to a multi-value dithering processor. The multi-value dithering processing circuit performs multi-value dither processing of the corrected image signal, and produces a printer drive signal for defining a printing pixel pattern for each pixel of the input image.