Nonlinear Diffusion Pdes
نویسنده
چکیده
The main theory behind nonlinear diffusion models is to use nonlinear PDEs to create a scale space representation that consists of gradually simplified images where some image features such as edges are maintained or even enhanced. The earliest nonlinear diffusion model proposed in image processing is the so-called anisotropic diffusion1 by Perona and Malik [2]. In their formulation, they replaced the constant diffusion coefficient of linear equation by a smooth nonincreasing diffusivity function g with g(0) = 1, g(s) ≥ 0, and lims→∞ g(s) = 0. As a consequence, the diffusivities become variable in both space and time. The Perona-Malik equation is
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