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We consider the problem of atmospheric tomography, as it appears for example in adaptive optics systems for extremely large telescopes. We derive a frame decomposition, i.e., a decomposition in terms of a frame, of the underlying…

Numerical Analysis · Mathematics 2021-12-06 Simon Hubmer , Ronny Ramlau

Atmospheric tomography, the problem of reconstructing atmospheric turbulence profiles from wavefront sensor measurements, is an integral part of many adaptive optics systems. It is used to enhance the image quality of ground-based…

Instrumentation and Methods for Astrophysics · Physics 2026-04-21 Lukas Weissinger , Simon Hubmer , Bernadett Stadler , Ronny Ramlau

Photoacoustic tomography (PAT) is a novel and promising technology in hybrid medical imaging that involves generating acoustic waves in the object of interest by stimulating electromagnetic energy. The acoustic wave is measured outside the…

Numerical Analysis · Mathematics 2022-08-24 Minam Moon , Injo Hur , Sunghwan Moon

We consider the decomposition of bounded linear operators on Hilbert spaces in terms of functions forming frames. Similar to the singular-value decomposition, the resulting frame decompositions encode information on the structure and…

Numerical Analysis · Mathematics 2021-05-26 Simon Hubmer , Ronny Ramlau

In this paper, we consider the atmospheric tomography operator, which describes the effect of turbulent atmospheric layers on incoming planar wavefronts. Given wavefronts from different guide stars, measured at a telescope, the inverse…

Numerical Analysis · Mathematics 2024-04-18 Ronny Ramlau , Bernadett Stadler

The next generation ground-based telescopes rely heavily on adaptive optics for overcoming the limitation of atmospheric turbulence. In the future adaptive optics modalities, like multi-conjugate adaptive optics (MCAO), atmospheric…

Numerical Analysis · Mathematics 2015-06-15 Tapio Helin , Mykhaylo Yudytskiy

Image degradation due to atmospheric turbulence is common while capturing images at long ranges. To mitigate the degradation due to turbulence which includes deformation and blur, we propose a generative single frame restoration algorithm…

Computer Vision and Pattern Recognition · Computer Science 2020-07-24 Chun Pong Lau , Hossein Souri , Rama Chellappa

Image restoration algorithms for atmospheric turbulence are known to be much more challenging to design than traditional ones such as blur or noise because the distortion caused by the turbulence is an entanglement of spatially varying…

Image and Video Processing · Electrical Eng. & Systems 2022-07-26 Zhiyuan Mao , Ajay Jaiswal , Zhangyang Wang , Stanley H. Chan

Recent work by Oberti et al, (Astron. Astrophys., 667, 48, 2022) argued and made a compelling case that classical astronomical adaptive optics (AO) tomography performance can be further enhanced by carefully designing and optically…

Instrumentation and Methods for Astrophysics · Physics 2025-12-22 Carlos M. Correia , Pierre Jouve , Jesse Cranney , Guido Agapito Cédric Taïssir Heritier

An important task when processing sensor data is to distinguish relevant from irrelevant data. This paper describes a method for an iterative singular value decomposition that maintains a model of the background via singular vectors…

Computer Vision and Pattern Recognition · Computer Science 2019-07-01 Günther Reitberger , Tomas Sauer

The paper surveys recent progress in establishing uniqueness and developing inversion formulas and algorithms for the thermoacoustic tomography. In mathematical terms, one deals with a rather special inverse problem for the wave equation.…

Analysis of PDEs · Mathematics 2009-02-02 M. Agranovsky , P. Kuchment , L. Kunyansky

Turbulence-degraded image frames are distorted by both turbulent deformations and space-time-varying blurs. To suppress these effects, we propose a multi-frame reconstruction scheme to recover a latent image from the observed image…

Computer Vision and Pattern Recognition · Computer Science 2017-12-12 Chun Pong Lau , Yu Hin Lai , Lok Ming Lui

Ground-based solar image restoration is a computationally expensive procedure that involves nonlinear optimization techniques. The presence of atmospheric turbulence produces perturbations in individual images that make it necessary to…

Instrumentation and Methods for Astrophysics · Physics 2023-07-26 A. Asensio Ramos , S. Esteban Pozuelo , C. Kuckein

State-of-the-art atmospheric turbulence image restoration methods utilize standard image processing tools such as optical flow, lucky region and blind deconvolution to restore the images. While promising results have been reported over the…

Image and Video Processing · Electrical Eng. & Systems 2019-05-21 Nicholas Chimitt , Zhiyuan Mao , Guanzhe Hong , Stanley H. Chan

Atmospheric turbulence distorts visual imagery and is always problematic for information interpretation by both human and machine. Most well-developed approaches to remove atmospheric turbulence distortion are model-based. However, these…

Computer Vision and Pattern Recognition · Computer Science 2022-05-10 Nantheera Anantrasirichai

Modern ground-based telescopes rely on a technology called adaptive optics (AO) in order to compensate for the loss of image quality caused by atmospheric turbulence. Next-generation AO systems designed for a wide field of view require a…

Numerical Analysis · Mathematics 2015-11-24 Tapio Helin , Stefan Kindermann , Daniela Saxenhuber

High-resolution ground-based solar imaging relies heavily on multi-object multi-frame blind deconvolution to correct for atmospheric turbulence. However, the traditional joint maximum likelihood estimation methods in which object and the…

Instrumentation and Methods for Astrophysics · Physics 2026-05-13 A. Asensio Ramos

In this paper we propose an approach to approximate a truncated singular value decomposition of a large structured matrix. By first decomposing the matrix into a sum of Kronecker products, our approach can be used to approximate a large…

Numerical Analysis · Mathematics 2018-04-03 Clarissa Garvey , Chang Meng , James G. Nagy

Multi-frame depth estimation improves over single-frame approaches by also leveraging geometric relationships between images via feature matching, in addition to learning appearance-based features. In this paper we revisit feature matching…

Computer Vision and Pattern Recognition · Computer Science 2022-06-14 Vitor Guizilini , Rares Ambrus , Dian Chen , Sergey Zakharov , Adrien Gaidon

In this paper we propose a new approach for tomographic reconstruction with spatially varying regularization parameter. Our work is based on the SA-TV image restoration model proposed in [3] where an automated parameter selection rule for…

Numerical Analysis · Mathematics 2018-11-27 Yiqiu Dong , Carola-Bibiane Schönlieb
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