An image processing apparatus includes a character data extraction unit, a contour data extraction unit, and an image density changing unit. The character data extraction unit extracts character data, forming a character image serving as a target to be read by an image reading apparatus, from image data. The contour data extraction unit extracts contour data forming a contour image of the character image from the image data. The image density changing unit changes an image density of the contour image base on the contour data extracted from the contour data extraction unit.