1. An object detection apparatus which detects a movable object in a region around a vehicle from a time series of images obtained through a camera mounted on the vehicle, the apparatus comprising: a feature point extraction unit which extracts a feature point contained in a feature region of each of the images in the time series; a correspondence degree computation unit which computes a degree of correspondence for each pair of the feature points, wherein one of the feature points in the each pair is each of one or more of the feature points extracted by the feature point extraction unit from one of two images taken by the camera at different times, and another of the feature points in the each pair is each of a plurality of the feature points extracted by the feature point extraction unit from the other of the two images; and a detection unit which detects the movable object on the basis of the degree of correspondence computed by the correspondence degree computation unit.