Qualitative representation of scenes along route

摘要

This paper proposes a method for representing qualitatively a route in an outdoor environment in terms of landmarks. A camera continuously scans the side-view and yields an intermediate representation called a panoramic representation. The objects in the scene are segmented based upon range and color information in the panoramic representation, and they are then arranged into a structure map which provides qualitative information on the environment structure. The objects which have distinctive features along the route are selected as the landmarks. When the same route is traversed again with a different camera speed, objects in the viewed scene are segmented and arranged in a new structure map. Since their relative spatial arrangement is invariant with the camera speed, the stored landmarks can be matched with the objects in the new structure map by a dynamic programming method according to their depth and range along the route. The correctness of matching is further verified by comparing their disparity template. Results of experiments in both a scaled model and a real outdoor world show the effectiveness and robustness of this method.