An image processing apparatus includes an object type determining unit that determines whether a drawing object in the input image data includes a color character group; a background area extracting unit that extracts the background area on which the color character group is formed in the drawing object; a monochromatic conversion unit that, when the drawing object is determined to include the color character group, generates monochromatic image data by performing monochromatic conversion of the input image data with minimum luminance of a main color; a pattern generating unit that, when the drawing object is determined to include the color character group, generates, according to the hue of the color character group, pattern image data to be added to the background area of the post-monochromatic-conversion color character group; and a synthesizing unit that synthesizes the monochromatic image data and the pattern image data.