Optimal boundary smoothing for curvature estimation

Computing a curvature function on a digitized boundary is an ill-posed problem due to the discrete nature of the boundary. Thus, the boundary needs to be smoothed before computing the curvature function. The authors use a constrained regularization technique to obtain the optimal smooth boundary. The curvature function is computed from this optimal smooth boundary. This method solves a common critical problem of current curvature estimation methods in determining a unique smoothing factor. This method is used to derive a curvature function which is invariant under rotation, scale, and translation