A Hough transform based approach to polyline approximation of object boundaries

A technique is presented for obtaining a polygonal approximation of object contours directly from the edge images. The technique is based on a new formulation of the Hough transform (HT) for aggregation of edge points into line segments. The space requirement of the HT is brought down by considering a different parameterization of straight lines. In this method, the process of edge linking and boundary approximation are combined into a single algorithm. Consequently, the scheme is computationally more efficient than the classical boundary approximation techniques which require use of a separate edge linking algorithm. Experimental results highlight the effectiveness of this method for approximating object boundaries of polygonal as well as curved shapes present in the images of complex multi-object scenes