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Related papers: Directional polynomial wavelets on spheres

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In this article, we introduce and investigate polynomial curvelets on spheres, which form a class of Parseval frames for $L^2(\mathbb{S}^{d-1})$, $d \geq 3$. The proposed construction offers a directionally sensitive multiscale…

Classical Analysis and ODEs · Mathematics 2026-03-16 Frederic Schoppert

We introduce a general framework for the construction of polynomial frames in $L^2(\mathbb{S}^{d-1})$, $d \geq 3$, where the frame functions are obtained as rotated versions of an initial sequence of polynomials $\Psi^j$, $j\in…

Classical Analysis and ODEs · Mathematics 2026-01-23 Marzieh Hasannasab , Larissa Kaldewey , Frederic Schoppert

We construct a directional spin wavelet framework on the sphere by generalising the scalar scale-discretised wavelet transform to signals of arbitrary spin. The resulting framework is the only wavelet framework defined natively on the…

Information Theory · Computer Science 2017-06-06 Jason D. McEwen , Boris Leistedt , Martin Büttner , Hiranya V. Peiris , Yves Wiaux

The major goal of the paper is to prove that discrete frames of (directional) wavelets derived from an approximate identity exist. Additionally, a kind of energy conservation property is shown to hold in the case when a wavelet family is…

Classical Analysis and ODEs · Mathematics 2018-03-06 Ilona Iglewska-Nowak

The paper shows that under some mild conditions $n$-dimensional spherical wavelets derived from approximate identities build semi-continuous frames. Moreover, for sufficiently dense grids Poisson wavelets on $n$-dimensional spheres…

Classical Analysis and ODEs · Mathematics 2018-03-09 Ilona Iglewska-Nowak

Here we present a method of constructing steerable wavelet frames in $L_2(\mathbb{R}^d)$ that generalizes and unifies previous approaches, including Simoncelli's pyramid and Riesz wavelets. The motivation for steerable wavelets is the need…

Classical Analysis and ODEs · Mathematics 2014-02-20 John Paul Ward , Michael Unser

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 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

In this paper, we propose a new method for the construction of multi-dimensional, wavelet-like families of affine frames, commonly referred to as framelets, with specific directional characteristics, small and compact support in space,…

Information Theory · Computer Science 2019-09-13 Nikolaos Atreas , Nikolaos Karantzas , Manos Papadakis , Theodoros Stavropoulos

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

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

A scheme to form a basis and a frame for a Hilbert space of quaternion valued square integrable function from a basis and a frame, respectively, of a Hilbert space of complex valued square integrable functions is introduced. Using the…

Mathematical Physics · Physics 2017-09-11 A. Askari Hemmat , K. Thirulogasanthar , A. Krzyzak

Recent work introduced a unified framework for steerable and directional wavelets in two and three dimensions that ensures many desirable properties, such as a multi-scale structure, fast transforms, and a flexible angular localization. We…

Numerical Analysis · Computer Science 2018-05-08 Christian Lessig

The paper presents a versatile library of quasi-analytic complex-valued wavelet packets (WPs) which originate from polynomial splines of arbitrary orders. The real parts of the quasi-analytic WPs are the regular spline-based orthonormal WPs…

Numerical Analysis · Mathematics 2020-08-13 Amir Averbuch , Pekka Neittaanmaki , Valery Zheludev

We present here a simple construction of a wavelet system for the three-dimensional ball, which we label \emph{Radial 3D Needlets}. The construction envisages a data collection environment where an observer located at the centre of the ball…

Instrumentation and Methods for Astrophysics · Physics 2014-12-03 Claudio Durastanti , Yabebal T. Fantaye , Frode K. Hansen , Domenico Marinucci , Isaac Z. Pesenson

In recent years directional multiscale transformations like the curvelet- or shearlet transformation have gained considerable attention. The reason for this is that these transforms are - unlike more traditional transforms like wavelets -…

Functional Analysis · Mathematics 2009-12-13 Philipp Grohs

In this paper we show that certain trigonometric polynomial shearlets which are special cases of directional de la Vall\'{e}e Poussin type wavelets are able to detect singularities along boundary curves of periodic characteristic functions.…

Functional Analysis · Mathematics 2021-02-10 Jürgen Prestin , Kevin Schober , Serhii A. Stasyuk

In this article, we develop a general method for constructing wavelets {|det A_j|^{1/2} g(A_jx-x_{j,k}): j in J, k in K}, on irregular lattices of the form X={x_{j,k} in R^d: j in J, k in K}, and with an arbitrary countable family of…

Classical Analysis and ODEs · Mathematics 2007-05-23 Akram Aldroubi , Carlos Cabrelli , Ursula M. Molter

A discrete frame for $L^2({\mathbb R}^d)$ is a countable sequence $\{e_j\}_{j\in J}$ in $L^2({\mathbb R}^d)$ together with real constants $0<A\leq B< \infty$ such that $$ A\|f\|_2^2 \leq \sum_{j\in J}|\langle f,e_j \rangle |^2 \leq…

Classical Analysis and ODEs · Mathematics 2021-02-05 Mahya Ghandehari , Kris Hollingsworth
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