A control unit of a console acquires first radiographic image data and second radiographic image data and determines whether a reference line which satisfies a predetermined accuracy for defining a bone mass is capable of being derived, on the basis of a pixel value of an initial soft region of a DXA profile indicating a correspondence relationship between a pixel position and the pixel value in a derivation region including a soft region and a bone region in a DXA image which is a difference image between a first radiographic image and a second radiographic image and is used to derive at least one of bone density or bone mineral content. In a case in which it is determined that the reference line is capable of being derived, the control unit derives the reference line on the basis of the pixel value of the initial soft region.
