1. An image processing apparatus, comprising: extraction means configured to extract a characteristic amount of a region in which a recognition object may possibly be included from within an image of a processing object; parameter retaining means configured to retain a parameter regarding the recognition object; context retaining means configured to retain a context regarding the recognition object; and decision means configured to decide based on the characteristic amount extracted by said extraction means, the parameter retained in said parameter retaining means, and a result of arithmetic operation performed using the context retained in said context retaining means whether or not an image in the region is the recognition object.