An information processing device, to be used in an image capturing device that illuminates an object by an illumination means and captures reflected light from the object as a reflection image by a capturing means, includes a determination means for determining an irradiation angle range for irradiating the object by the illumination means, on the basis of two types of inclination statistic values that are values corresponding to the inclination distribution of the unevenness existing on a surface of the object.