Model based corner detection

A method is presented to correct an approximate polygonal sketch of an image object boundary by adjusting the location of each corner point in the sketch. The method is suitable for the segmentation of unknown images using interactive techniques, and for locating object boundaries in model-based segmentation. For each point, p, at which two lines meet in an open or closed polygonal sketch, a corner segmentation model is derived based on the angle, orientation and scale of the corner defined, and the image function f(x, y) in the immediate region about p. A corner template is then constructed and matched in a small neighborhood about p, thereby providing a corrected polygonal sketch. The segmentation model is correct in 95% of the cases, and the corner is accurately located