[Problems to be Solved] By considering not only an application condition of radiation applied to a subject but also a thickness of the subject, allowing a radiation image having a contrast according to a desired application condition to be obtained. [Means for Solving the Problems] A composition information obtaining unit (82) calculates a mammary gland/fat ratio and a first information obtaining unit (84) obtains imaged contrast information representing a contrast of the radiation image. A second information obtaining unit (86) sets target application condition of X-ray, and obtains target contrast information representing an intended contrast for the radiation image based on the intended application condition. A contrast correction amount determination unit (88) determines a contrast correction amount based on the imaged contrast information and the target contrast information. An image processing unit (92) performs image processing, including gradation processing based on the determined contrast correction amount, on the radiation image, and obtains a processed radiation image.
