To make reproducibility of an image more natural than that of a conventional one even with a plurality of methods for reducing gradation level.

An image processing apparatus 1 includes: a screen processing part 104 for screen processing of an input image; an error diffusion processing part 103 for an error diffusion processing of the input image; a mixed ratio determination processing part 105 for determining the mixed ration between the input image subject to the screen processing and the image subject to the error diffusion processing based on detection of the concentration of the input image; and a mix processing part 107 for mixing the input image subject to the screen processing with the image subject to the error diffusion processing according to the determined ratio.