An image processing device includes an acquisition section, first conversion section, determination section, filtering section, and second conversion section. The acquisition section acquires first image data defined by a plurality of color components. The first conversion section converts, for each pixel data, the plurality of color components into converted pixel data defined by a luminance and a color difference. The determination section determines whether or not each converted pixel data is target pixel data having a black character attribute. The filtering section performs a filtering process on a luminance of each target pixel data using a filter coefficient to obtain processed pixel data defined by the luminance and the color difference. The filter coefficient enhances a difference in the luminance between the each target pixel data and neighboring pixel data. The second conversion section converts each processed pixel data into updated pixel data defined by the plurality of color components.