Steerable Filters from Erlang Functions
نویسنده
چکیده
Scale and orientation steerable 2D filters are constructed using a frame of Erlang functions in the Fourier domain. Erlang forms for the radial frequency characteristic are shown to provide complex quadrature filters which can be steered in a scale parameter, . Oriented, spatial domain filters are constructed by imposing an appropriate angular selectivity in the frequency domain. A filter bank is designed, and outputs of the filters of the bank are steered to construct an oriented scale-space decomposition of an image subband. Some applications are discussed.
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