Morphologic edge detection in range images

Range images provide an explicit encoding of the shape and the geometric structure of the objects in the image from the point of view of the sensor. Morphological operators are ideally suited for analysis of range images due to their inherently geometric nature. Most morphological edge operators meant for intensity images are concerned only with jump and ramp edges and not with crease and roof edges. Since roof and crease edges do not correspond to depth discontinuity, such operators cannot be used to detect these edges in range images. In this paper, edge detection schemes for range images based on morphological operations are presented. It is shown that by a suitable choice of the structuring element, selective crease and roof edges can be extracted, and by using multiple structuring elements oriented in different directions, directional sensitivity to edge detection can be incorporated. Several examples of morphological edge detection in range images are presented.