Smoothers for Discontinuous Signals
نویسندگان
چکیده
First we explain the interplay between robust loss functions non linear lters and Bayes smoothers for edge preserving image recon struction Then we prove the surprising fact that maximum posterior smoothers are nonlinear lters A generalized Potts prior for segmen tation and piecewise smoothing of noisy signals and images is adopted For one dimensional signals an exact solution for the maximum poste rior mode based on dynamic programming is derived After some results on the performance of nonlinear lters on jumps and ramps we nally introduce a cascade of nonlinear lters with varying scale parameters and discuss the choice of parameters for segmentation and piecewise smoothing
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