Abstract Discrete curvature computation of digital curves is widely applied to various tasks of image analysis and computer vision. A computational method of discrete curvature, U-chord curvature, is proposed. For each point in a digital curve, its support region is determined by two points with a given chord distance to the point, and then the U-chord curvature of the point is estimated. A theoretical analysis shows that there is a close relationship between the U-chord curvature and the real curvature of the curve. Compared with the existing computational methods of discrete curvature, the U-chord curvature is more stable under rotation transformations and noise condition. Therefore, it is suitable for image and vision tasks which require a high stability of curvature estimation, such as curve matching. Simulation experiments show the efficiency of the proposed method.
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2014, Vol. 27 
