Camera parameter calculation apparatus, camera parameter calculation method, and non-transitory computer readable medium storing program

In a camera calibration apparatus (10), an external parameter calculation unit (13) calculates a rotation vector and a rotation matrix using the normalized start point coordinates, the normalized end point coordinates, and an "evaluation function" obtained by the normalized coordinate transformation unit (12) for each normal vector in the image plane and then outputs the calculated translation vector and rotation matrix. The normal vectors in the image plane respectively correspond to a plurality of normal vectors in a world coordinate space with respect to a reference plane in the world coordinate space. The evaluation function is for overdetermining a rotation parameter around a normal line with respect to the above reference plane in the world coordinate space.