Discrete spherical means of directional derivatives and their applications
نویسندگان
چکیده
The goal of this paper is two-fold. First we study theoretical properties of discrete spherical means of directional derivatives of a function. Then we focus on the two-dimensional case and use discrete circular means to derive rotation-equivariant discrete approximations of linear and nonlinear firstand second-order differential operators. Applications to nonlinear filtering of digital images and surface curvature estimation are considered.
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تاریخ انتشار 2010