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Wreath Product Group Transform

In the recent paper "A Wreath Product Approach to Signal and Image Processing: Part I --- Multiresolution Analysis", by Foote, Mirchandini, Rockmore, Healy, and Olson, IEEE Trans. on Signal Processing, Vol. 48, pp. 102--132, transforms arising from iterated wreath products of cyclic groups have been proposed for image processing. The following structured, sparse matrix factorization represents a fast algorithm for a wreath product transform of size 16 (given on p. 117 of the paper), and has been automatically generated (even in the presented Latex format) using the package AREP.

fast wreath product transform
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