A calibration information calculation unit 340 calculates the first coordinate positions of feature points included in images obtained by an image sensing apparatus at timings from an instruction unit 350 using position data, on world coordinate system, of a plurality of feature points held by a world coordinate holding unit 310 and the measured values of a position/posture sensor 130 input to a data management unit 330 at the timings. The unit 340 receives the second coordinate positions, which are acquired by an image coordinate acquisition unit 320, of the feature points included in the images obtained by the image sensing device at the timings. The unit 340 calculates calibration information using the first and second coordinate positions.