An image acquisition block of an information processing apparatus acquires stereo images taken by a first camera and a second camera that make up an imaging apparatus. An input information acquisition block accepts a user manipulation. A first positional information acquisition block of a positional information generation block identifies an approximate position of an object to be imaged through predetermined means. A second positional information acquisition block determines an estimated distance range of a target on the basis of the identified approximate position of the object to be imaged, detects corresponding points by executing block matching on stereo images thorough only a search range corresponding to the determined estimated distance range, and obtains a position of the target with high resolution and accuracy. An output information generation block generates output data on the basis of the position of that target and outputs the generated output data.