A dot detection section of a dot-interference detection section detects a portion where pixels are arranged as "dark-bright-dark" or "bright-dark-bright" in the horizontal direction, within a Y signal containing dot interference, separated by a YC separation process, and outputs the detection result as dot values to a horizontal array checking section and a vertical array checking section. The horizontal array checking section detects whether or not dot values of a predetermined number of pixels arranged horizontally in such a manner as to contain a subject pixel, have the same value. The vertical array checking section detects whether or not dot values of a predetermined number of pixels arranged vertically in such a manner as to contain a subject pixel, are alternately generated as 1 and 2. An enhancement processing section performs an enhancement process on the Y signal of portions other than the portions where dot interference occurs.