Patent ID: 8687906

Claim:
An image processing device, comprising: a first output unit that performs predetermined image processing for image data, and outputs image data having m bits per pixel; a second output unit that performs pseudo gradation-increase processing by a dither method or a multilevel error diffusion method for the image data output from the first output unit, and outputs image data having n bits per pixel, where n<m; and a compression unit that compresses the image data output from the second output unit, wherein, when a dither matrix that the second output unit uses for the pseudo gradation-increase processing by the dither method or a filter that the second output unit uses for the pseudo gradation-increase processing by the multilevel error diffusion method is divided into a plurality of pixel groups each including a plurality of adjacent pixels and when each of the pixel groups serves as a unit, processing parameters of the dither matrix or the filter respectively set for pixels in the same pixel group are similar to each other as compared with processing parameters respectively set for pixels in different pixel groups.