Edge-Preserving Piecewise Linear Image Smoothing Using Piecewise Constant Filters

Roof-edge preserving image smoothing based on MRFs

A novel Markov random field (MRF) model is proposed for roof-edge (as well as step-edge) preserving image smoothing. Image surfaces containing roof-edges are represented by piecewise continuous polynomial functions governed by a few parameters. Piecewise smoothness constraint is imposed on these parameters rather than on the surface heights as is in traditional models for step-edges. In this wa...

A Quantitative Assessment of Edge Preserving Smoothing Filters for Edge Detection

Edge detection algorithms have traditionally utilized the Gaussian Linear Filter (GLF) for image smoothing. Although GLF has very good properties in removing noise and unwanted artifacts from an image, it is also known to remove many valid edges. To cope with this problem, edge preserving smoothing filters have been proposed and they have recently attracted increased attention. In this paper, w...

Piecewise Constant Controlled Linear Fuzzy Systems

Smoothers for Discontinuous Signals

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 p...

Edge-preserving prefiltering for document image binarization

We propose a novel coplanar filter, which exploits the coplanarity of gray-level distribution of neighboring pixels, to pre-filter the document images. Experiments show that the proposed filter exhibits the following desired properties for document image binarization: (1) impulsive noise removal, (2) piecewise smoothing, and (3) sharp edge preservation.