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In this manuscript, we obtain a plane wave decomposition for the delta distribution in superspace, provided that the superdimension is not odd and negative. This decomposition allows for explicit inversion formulas for the super Radon…

Mathematical Physics · Physics 2021-07-13 Alí Guzmán Adán , Irene Sabadini , Frank Sommen

Benefiting from a relatively larger aperture's angle, and in combination with a wide transmitting bandwidth, near-field synthetic aperture radar (SAR) provides a high-resolution image of a target's scattering distribution-hot spots.…

Image and Video Processing · Electrical Eng. & Systems 2022-11-29 Xu Zhan , Xiaoling Zhang , Wensi Zhang , Jun Shi , Shunjun Wei , Tianjiao Zeng

The significance of the broken ray transform (BRT) is due to its occurrence in a number of modalities spanning optical, x-ray, and nuclear imaging. When data are indexed by the scatter location, the BRT is both linear and shift invariant.…

Signal Processing · Electrical Eng. & Systems 2019-08-07 Michael R. Walker , Joseph A. O'Sullivan

Omnidirectional images and spherical representations of $3D$ shapes cannot be processed with conventional 2D convolutional neural networks (CNNs) as the unwrapping leads to large distortion. Using fast implementations of spherical and…

Computer Vision and Pattern Recognition · Computer Science 2020-12-09 Suhas Lohit , Shubhendu Trivedi

This paper proposes a spatial-Radon domain CT image reconstruction model based on data-driven tight frames (SRD-DDTF). The proposed SRD-DDTF model combines the idea of joint image and Radon domain inpainting model of \cite{Dong2013X} and…

Medical Physics · Physics 2016-01-27 Ruohan Zhan , Bin Dong

A method of approximating the inverse Radon transform on the plane by integrating against a smooth kernel is investigated. For piecewise smooth integrable functions, convergence theorems are proven and Gibbs phenomena are ruled out.…

Numerical Analysis · Mathematics 2019-10-22 Shavkat Alimov , Joseph David , Alexander Nolte , Julie Sherman

The relation between Radon transform and orthogonal expansions of a function on the unit ball in $\RR^d$ is exploited. A compact formula for the partial sums of the expansion is given in terms of the Radon transform, which leads to…

Mathematical Physics · Physics 2009-11-13 Yuan Xu

The transform considered in the paper integrates a function supported in the unit disk on the plane over all circles centered at the boundary of this disk. Such circular Radon transform arises in several contemporary imaging techniques, as…

General Mathematics · Mathematics 2007-05-23 Gaik Ambartsoumian , Peter Kuchment

Inverse rendering aims to estimate physical attributes of a scene, e.g., reflectance, geometry, and lighting, from image(s). Inverse rendering has been studied primarily for single objects or with methods that solve for only one of the…

Computer Vision and Pattern Recognition · Computer Science 2019-09-17 Soumyadip Sengupta , Jinwei Gu , Kihwan Kim , Guilin Liu , David W. Jacobs , Jan Kautz

The reconstruction of images from their corresponding noisy Radon transform is a typical example of an ill-posed linear inverse problem as arising in the application of computerized tomography (CT). As the (naive) solution does not depend…

The sparse-driven radar imaging can obtain the high-resolution images about target scene with the down-sampled data. However, the huge computational complexity of the classical sparse recovery method for the particular situation seriously…

Quantum Physics · Physics 2022-01-05 Xiaowen Liu , Chen Dong , Ying Luo , Le Kang , Yong Liu , Qun Zhang

Using convolutional neural networks for 360images can induce sub-optimal performance due to distortions entailed by a planar projection. The distortion gets deteriorated when a rotation is applied to the 360image. Thus, many researches…

Computer Vision and Pattern Recognition · Computer Science 2022-02-14 Sungmin Cho , Raehyuk Jung , Junseok Kwon

In this article, we consider the limited data problem for spherical mean transform. We characterize the generation and strength of the artifacts in a reconstruction formula. In contrast to the third's author work [Ngu15b], the observation…

Analysis of PDEs · Mathematics 2016-01-20 Lyudmyla L. Barannyk , Jürgen Frikel , Linh V. Nguyen

This work characterizes the range of the single-quadrant approximate discrete Radon transform (ADRT) of square images. The characterization follows from a set of linear constraints on the codomain. We show that for data satisfying these…

Numerical Analysis · Mathematics 2022-03-23 Weilin Li , Kui Ren , Donsub Rim

The sonar transform in geometric tomography maps functions on the Euclidean half-space to integrals of those functions over hemispheres centered on the boundary hyperplane. We obtain sharp $L^p$-$L^q$ estimates for this transform and new…

Functional Analysis · Mathematics 2022-06-14 Boris Rubin

Moment methods to reconstruct images from their Radon transforms are both natural and useful. They can be used to suppress noise or other spurious effects and can lead to highly efficient reconstructions from relatively few projections. We…

Functional Analysis · Mathematics 2019-03-08 H. Choi , V. Ginting , F. Jafari , R. Mnatsakanov

Omnidirectional vision is becoming increasingly relevant as more efficient $360^o$ image acquisition is now possible. However, the lack of annotated $360^o$ datasets has hindered the application of deep learning techniques on spherical…

Computer Vision and Pattern Recognition · Computer Science 2019-09-17 Antonis Karakottas , Nikolaos Zioulis , Stamatis Samaras , Dimitrios Ataloglou , Vasileios Gkitsas , Dimitrios Zarpalas , Petros Daras

The cone-beam transform consists of integrating a function defined on the three-dimensional space along every ray that starts on a certain scanning set. Based on Grangeat's formula, Louis [2016, Inverse Problems 32 115005] states…

Numerical Analysis · Mathematics 2021-08-13 Michael Quellmalz , Ralf Hielscher , Alfred K. Louis

The ability to directly follow and time resolve the rearrangement of the nuclei within molecules is a frontier of science that requires atomic spatial and few-femtosecond temporal resolutions. While laser induced electron diffraction can…

The Funk-Radon transform assigns to a function defined on the unit sphere its integrals along all great circles of the sphere. In this paper, we consider a frame decomposition of the Funk-Radon transform, which is a flexible alternative to…

Numerical Analysis · Mathematics 2023-05-16 Michael Quellmalz , Lukas Weissinger , Simon Hubmer , Paul D. Erchinger
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