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arXiv · 1406.0513

Window-Dependent Bases for Efficient Representations of the Stockwell Transform

Ubertino Battisti·Luigi Riba
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Abstract

Since its appearing in 1996, the Stockwell transform (S-transform) has been applied to medical imaging, geophysics and signal processing in general. In this paper, we prove that the system of functions (so-called DOST basis) is indeed an orthonormal basis of L^2([0,1]), which is time-frequency localized, in the sense of Donoho-Stark Theorem (1989). Our approach provides a unified setting in which to study the Stockwell transform (associated to different admissible windows) and its orthogonal decomposition. Finally, we introduce a fast -- O(N log N) -- algorithm to compute the Stockwell coefficients for an admissible window. Our algorithm extends the one proposed by Y. Wang and J. Orchard (2009).

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BibTeXRIS

Ubertino Battisti, Luigi Riba. 2014-12-31. Window-Dependent Bases for Efficient Representations of the Stockwell Transform. https://arxiv.org/abs/1406.0513

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