An image-capture device 1 includes: an image acquisition unit 111 that acquires a plurality of images that are successively captured; an identification unit 112 that identifies a golf ball B as a predetermined object in each of the plurality of images; a rotation calculation unit 113 that calculates the number of rotations of the predetermined object; a movement amount calculation unit 114 that calculates a total movement amount that the golf ball B has moved; and a slippage amount calculation unit 115 that calculates a slippage amount based on the number of rotations as well as the total movement amount.