In an image processing apparatus that performs a dither processing using a dither matrix based on the result of determination of the segmentation class to which the pixel to be processed belongs, to perform the dither processing, any of a plurality of pairs of threshold values is selected according to the result of determination of the segmentation class, and the selected pair of threshold values are compared with the value of the pixel to be processed, which are set so that in correspondence with each position of a dither matrix of a same configuration and a same size, a different dither processing is performed according to the result of determination of the segmentation class on part of the dither matrix and a same dither processing is performed irrespective of the result of determination of the segmentation class on the remainder of the dither matrix.