A region detection image is obtained by the detection of a subject region of a radiographic image in which radiation is transmitted through a subject and reaches a radiation detection unit and a direct radiation region of the radiographic image in which the radiation directly reaches the radiation detection unit without being transmitted through the subject. A scattered radiation image about scattered radiation components is obtained on the basis of the region detection image and scattered-radiation-spread information about the spread of scattered radiation. A radiographic image from which the scattered radiation components have been removed is obtained by the subtraction of the scattered radiation image from the radiographic image.
