PAIRED ANISOTROPIC DISTRIBUTION FOR IMAGE SELECTIVE SMOOTHING

‎In this paper‎, ‎we present a novel approach for image selective smoothing by the evolution of two paired nonlinear‎ ‎partial differential equations‎. ‎The distribution coefficient in de-noising equation controls the speed of distribution‎, ‎and is‎ ‎determined by the edge-strength function‎. ‎In the previous works‎, ‎the edge-strength function depends on isotropic‎ ‎smoothing of the image‎, ‎which results in failing to preserve corners and junctions‎, ‎and may also result in failing to resolve‎ ‎small features that are closely grouped together‎. ‎The proposed approach obtains the edge-strength function by solving a‎ ‎nonlinear distribution equation governed by the norm of the image gradient‎. ‎This edge-strength function is then introduced‎ ‎into a well-studied anisotropic distribution model to yield a regularized distribution coefficient for image smoothing‎. ‎An explicit‎ ‎numerical scheme is employed to efficiently solve these two paired equations‎. ‎Compared with the existing methods‎, ‎the‎ ‎proposed approach has the advantages of more detailed preservation and implementational simplicity‎. ‎Experimental results‎ ‎on the synthesis and real images confirm the validity of the proposed approach‎.