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Related papers: Directional spin wavelets on the sphere

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A new spin wavelet transform on the sphere is proposed to analyse the polarisation of the cosmic microwave background (CMB), a spin $\pm 2$ signal observed on the celestial sphere. The scalar directional scale-discretised wavelet transform…

Instrumentation and Methods for Astrophysics · Physics 2014-12-04 Jason D. McEwen , Martin Büttner , Boris Leistedt , Hiranya V. Peiris , Pierre Vandergheynst , Yves Wiaux

We review scale-discretized wavelets on the sphere, which are directional and allow one to probe oriented structure in data defined on the sphere. Furthermore, scale-discretized wavelets allow in practice the exact synthesis of a signal…

Information Theory · Computer Science 2013-12-10 J. D. McEwen , P. Vandergheynst , Y. Wiaux

Scale-discretised wavelets yield a directional wavelet framework on the sphere where a signal can be probed not only in scale and position but also in orientation. Furthermore, a signal can be synthesised from its wavelet coefficients…

Information Theory · Computer Science 2017-08-17 Jason D. McEwen , Claudio Durastanti , Yves Wiaux

We discuss a new scale-discretised directional wavelet transform to analyse spin signals defined on the sphere, in particular the polarisation of the cosmic microwave background (CMB).

Instrumentation and Methods for Astrophysics · Physics 2015-02-12 Boris Leistedt , Jason D. McEwen , Martin Büttner , Hiranya V. Peiris , Pierre Vandergheynst , Yves Wiaux

A new construction of a directional continuous wavelet analysis on the sphere is derived herein. We adopt the harmonic scaling idea for the spherical dilation operator recently proposed by Sanz et al. but extend the analysis to a more…

Astrophysics · Physics 2011-10-28 J. D. McEwen , M. P. Hobson , A. N. Lasenby

Wavelets on the sphere are reintroduced and further developed independently of the original group theoretic formalism, in an equivalent, but more straightforward approach. These developments are motivated by the interest of the scale-space…

Astrophysics · Physics 2008-11-26 Y. Wiaux , L. Jacques , P. Vandergheynst

In recent years, a rapidly growing literature has focussed on the construction of wavelet systems to analyze functions defined on the sphere. Our purpose in this paper is to generalize these constructions to situations where sections of…

Classical Analysis and ODEs · Mathematics 2010-06-22 Daryl Geller , Domenico Marinucci

We describe S2LET, a fast and robust implementation of the scale-discretised wavelet transform on the sphere. Wavelets are constructed through a tiling of the harmonic line and can be used to probe spatially localised, scale-depended…

Information Theory · Computer Science 2013-10-29 B. Leistedt , J. D. McEwen , P. Vandergheynst , Y. Wiaux

Segmentation, a useful/powerful technique in pattern recognition, is the process of identifying object outlines within images. There are a number of efficient algorithms for segmentation in Euclidean space that depend on the variational…

Computer Vision and Pattern Recognition · Computer Science 2019-11-12 Xiaohao Cai , Christopher G. R. Wallis , Jennifer Y. H. Chan , Jason D. McEwen

Curvelets are efficient to represent highly anisotropic signal content, such as a local linear and curvilinear structure. First-generation curvelets on the sphere, however, suffered from blocking artefacts. We present a new…

Information Theory · Computer Science 2016-11-29 Jennifer Y. H. Chan , Boris Leistedt , Thomas D. Kitching , Jason D. McEwen

A new formalism is derived for the analysis and exact reconstruction of band-limited signals on the sphere with directional wavelets. It represents an evolution of the wavelet formalism developed by Antoine & Vandergheynst (1999) and Wiaux…

Astrophysics · Physics 2008-12-09 Y. Wiaux , J. D. McEwen , P. Vandergheynst , O. Blanc

Directional wavelet dictionaries are hierarchical representations which efficiently capture and segment information across scale, location and orientation. Such representations demonstrate a particular affinity to physical signals, which…

Instrumentation and Methods for Astrophysics · Physics 2024-03-15 Matthew A. Price , Alicja Polanska , Jessica Whitney , Jason D. McEwen

In the present paper, a construction of spin weighted spherical wavelets is presented. It is based on approximate identities, the wavelets are defined for a continuous set of parameters, and the wavelet transform is invertible directly by…

Functional Analysis · Mathematics 2018-04-16 Ilona Iglewska-Nowak

Scalar wavelets have been used extensively in the analysis of Cosmic Microwave Background (CMB) temperature maps. Spin needlets are a new form of (spin) wavelets which were introduced in the mathematical literature by Geller and Marinucci…

In this article, we construct discrete tight frames for $L^2(\mathbb{S}^{d-1})$, $d\geq3$, which consist of localized polynomial wavelets with adjustable degrees of directionality. In contrast to the well studied isotropic case, these…

Classical Analysis and ODEs · Mathematics 2025-12-09 Frederic Schoppert

We describe the construction of a spherical wavelet analysis through the inverse stereographic projection of the Euclidean planar wavelet framework, introduced originally by Antoine and Vandergheynst and developed further by Wiaux et al.…

Astrophysics · Physics 2011-10-28 J. D. McEwen , M. P. Hobson , D. J. Mortlock , A. N. Lasenby

We construct spherical wavelets based on approximate identities that are directional, i.e. not rotation-invariant, and have an adaptive angular selectivity. The problem of how to find a proper representation of distinct kinds of details of…

Classical Analysis and ODEs · Mathematics 2018-04-10 Ilona Iglewska-Nowak

A new method is presented for the construction of a natural continuous wavelet transform on the sphere. It incorporates the analysis and synthesis with the same wavelet and the definition of translations and dilations on the sphere through…

Astrophysics · Physics 2007-05-23 J. L. Sanz , D. Herranz , M. Lopez-Caniego , F. Argueso

Wavelets are widely used in various disciplines to analyse signals both in space and scale. Whilst many fields measure data on manifolds (i.e., the sphere), often data are only observed on a partial region of the manifold. Wavelets are a…

Information Theory · Computer Science 2023-04-24 Patrick J. Roddy

In the general context of complex data processing, this paper reviews a recent practical approach to the continuous wavelet formalism on the sphere. This formalism notably yields a correspondence principle which relates wavelets on the…

Astrophysics · Physics 2007-08-14 Y. Wiaux , J. D. McEwen , P. Vielva
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