Le proposte di nuovi seminari vanno inviate al Prof. Sandro Coriasco - sandro.coriasco[AT]unito.it o alla Prof.ssa Vivina Barutello - vivina.barutello[AT]unito.it

E' possibile tenere i seminari, e/o parteciparvi, anche tramite applicativi di web-conferencing, previo accordo con gli organizzatori

# SEMINARI DI ANALISI MATEMATICA

## Evento

Titolo:
Windows-dependent bases for efficient representations of the Stockwell transform
Quando:
10.12.2014 13.30 h
Dove:
Palazzo Campana - Torino
Aula:
Aula C
Relatore:
Dott. Ubertino Battisti
Afferenza:
Università degli Studi di Torino
Proponente:
V. Barutello, S. Coriasco
Locandina:

## Descrizione

Since its appearing in 1996,the Stockwell transform (S-transform) has been used as a tool in medical imaging, geophysics and signal processing in general. In this talk, we prove that the system of functions (so-called DOST basis), introduced by R. Stockwell in 2007, is indeed an orthonormal basis of $$L^2([0,1])$$, which is a time-frequency localized basis, in the sense of Donoho-Stark Theorem. This approach provides a unified setting in which to study the Stockwell transform and its orthogonal decomposition in the framework of generalized Stockwell transforms, defined by of Wong and Zhu in 2007. Then, we introduce a fast -- $$\mathcal{O}\left(N \log N \right)$$ -- algorithm to compute the Stockwell coefficients for general windows. This algorithm includes the one proposed by Wang in 2009 as a special case. The results are obtained in collaboration with Luigi Riba. Finally I will introduce some applications of the DOST to signal processing, in particular some filtrations procedures and watermarking schemes. In some of them the transform we use is the real counterpart of the DOST, called DCST.

## Sede

Sede:
Palazzo Campana   -   Sito web
Via:
Via Carlo Alberto, 10
Cap:
10123
Città:
Torino
Provincia:
To
Paese:

## Descrizione

Dipartimento di Matematica, Università degli Studi di Torino