Patent ID: 6750984
Filing Date: 2004-06-15
Classification: H04N

Abstract:
An image processing apparatus which carries out a process of discriminating characteristics of a region including an object pixel in order to optimally process an original document which may contain a mixture of different kinds of image regions including characters, photographs and halftone regions, according to characteristics of each image region, comprising:a mask setting circuit for setting within the region including the object pixel a mask of a predetermined shape so as to contain therein the object pixel; a sub-region mask generation circuit for generating sub-region masks, each smaller than the mask set by the mask setting circuit, sequentially in different positions with in the mask set by the mask setting circuit, to obtain a sum of pixel densities within each of the sub-region masks; a parameter calculation circuit for calculating a parameter within the mask, using the sum of pixel densities obtained by the sub-region mask generation circuit; multi-valuing means for performing a multi-valuing process using the parameter calculated by the parameter calculation circuit; characteristic signal generating means for generating from distribution of multi-valued data generated by the multi-valuing means, within the mask, a characteristic signal represented by the multi-valued data; and region discriminating means for discriminating the characteristics of the region, based on the characteristic signal supplied from the characteristic signal generating means.