PROBLEM TO BE SOLVED: To improve reduction in contrast due to the influence of a scattered ray in a radiation image.SOLUTION: A frequency decomposition part 42 performs frequency decomposition on a radiation image to generate a band image indicating a frequency component for each of a plurality of frequency bands. A reference image generation part 43 generates a reference image indicating information related to a scattered ray included in the radiation image to generate a plurality of band reference images corresponding to the plurality of frequency bands from the reference image. A band image conversion part 44 performs conversion between mutually-corresponding pixels of the band reference image and the band image in the mutually-corresponding frequency bands to generate a converted band image. A synthesis part 46 synthesizes the converted band image to generate a processed radiation image with converted contrast.SELECTED DRAWING: Figure 2
