Image processor with improved discrimination between character image and tonal image

摘要

An image processor in which a high-frequency component of image signals is diminished, and a density value of each of the "diminished" image signals is compared with a first reference value in a first comparator. A first classifier is provided for classifying the image signals into a character image and a tonal image based on a signal output from the first comparator. A length or an area of an image signal classified into the tonal image is measured, and a second comparator is provided for comparing the length or area of a measured image signal measured with a second reference value corresponding to a reference length or a reference area. A second classifier is provided for further classifying an image signal below the second reference value from the second comparator into an image signal of the character image.