Method for self localization using parallel projection model

A method of recognizing a self location of an image acquisition device by acquiring an image of three or more reference objects, the method comprising:

• setting an actual camera plane, three or more reference object planes, and three or more virtual viewable planes located between the actual camera plane and the reference object planes;
• projecting the reference objects to a corresponding one of the virtual viewable planes;
• calculating a distance between a viewing axis of the image acquisition device and the reference objects and a distance between the viewing axis and images on the actual camera plane, the images corresponding to the reference objects;
• calculating an orientation of the image acquisition device by selecting an initial orientation by using two pairs of reference points to minimize an error distance and repeatedly computing the orientation of the image acquisition device by using the initial orientation and the error distance;
• and
• sensing the self location by using the orientation, a zoom factor, and coordinates of the reference objects,
• wherein the zoom factor is a ratio of a length of the reference object plane and a distance between the reference object plane and the virtual viewable plane, and
• the actual camera plane, the virtual viewable plane, and the reference object plane are perpendicular to the viewing axis.