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We describe a method for recovering the irradiance underlying a collection of images corrupted by atmospheric turbulence. Since supervised data is often technically impossible to obtain, assumptions and biases have to be imposed to solve…

Computer Vision and Pattern Recognition · Computer Science 2024-06-25 Dong Lao , Congli Wang , Alex Wong , Stefano Soatto

Photography is the cornerstone of modern astronomical and space research. However, most astronomical images captured by ground-based telescopes suffer from atmospheric turbulence, resulting in degraded imaging quality. While multi-frame…

Computer Vision and Pattern Recognition · Computer Science 2025-06-04 Joonyeoup Kim , Yu Yuan , Xingguang Zhang , Xijun Wang , Stanley Chan

The image reconstruction problem of the tomographic imaging technique magnetic particle imaging (MPI) requires the solution of a linear inverse problem. One prerequisite for this task is that the imaging operator that describes the mapping…

Computational Physics · Physics 2019-07-12 Tobias Kluth , Patryk Szwargulski , Tobias Knopp

This contribution deals with image restoration in optical systems with coherent illumination, which is an important topic in astronomy, coherent microscopy and radar imaging. Such optical systems suffer from wavefront distortions, which are…

Instrumentation and Methods for Astrophysics · Physics 2017-04-04 Claudius Zelenka , Reinhard Koch

The modulation transfer function (MTF) is widely used to characterise the performance of optical systems. Measuring it is costly and it is thus rarely available for a given lens specimen. Instead, MTFs based on simulations or, at best, MTFs…

Computer Vision and Pattern Recognition · Computer Science 2018-05-07 Matthias Bauer , Valentin Volchkov , Michael Hirsch , Bernhard Schölkopf

Atmospheric optical turbulence can be a significant source of image degradation, particularly in long range imaging applications. Many turbulence mitigation algorithms rely on an optical transfer function (OTF) model that includes the Fried…

Image and Video Processing · Electrical Eng. & Systems 2021-08-03 Russell C. Hardie , Michael A. Rucci , Santasri Bose-Pillai , Richard Van Hook

We study an inverse problem for a coupled system of semilinear Helmholtz equations where we are interested in reconstructing multiple coefficients in the system from internal data measured in applications such as thermoacoustic imaging. We…

Analysis of PDEs · Mathematics 2023-07-06 Kui Ren , Nathan Soedjak

Video sequence capturing through refractive dynamic media, such as a turbulent air or water surface, often suffer from severe geometric distortions and temporal instability. While recent advances address mild atmospheric turbulence, no…

Correlated imaging through atmospheric turbulence is studied, and the analytical expressions describing turbulence effects on image resolution are derived. Compared with direct imaging, correlated imaging can reduce the influence of…

Optics · Physics 2015-05-19 Pengli Zhang , Wenlin Gong , Xia Shen , Shensheng Han

Image retrieval is an important problem in the area of multimedia processing. This paper presents two new curvelet-based algorithms for texture retrieval which are suitable for use in constrained-memory devices. The developed algorithms are…

Image and Video Processing · Electrical Eng. & Systems 2019-05-27 Hasan Al-Marzouqi , Yuting Hu , Ghassan AlRegib

The Speckle Imager via MUlti Layer Atmospheric Turbulence Object Reconstructor (SIMULATOR) is a lab-based testbed instrument developed to test for speckle correlation-based techniques in the optical regime. However, this instrument can be…

Instrumentation and Methods for Astrophysics · Physics 2022-08-11 Sorabh Chhabra , Abhay A. Kohok , Bhushan S. Joshi , A. N. Ramprakash , Chaitanya V. Rajarshi , Rani S. Bhandare

In this work, we extract the optical flow field corresponding to moving objects from an image sequence of a scene impacted by atmospheric turbulence \emph{and} captured from a moving camera. Our procedure first computes the optical flow…

Computer Vision and Pattern Recognition · Computer Science 2024-10-30 Nicholas Ferrante , Jerome Gilles , Shibin Parameswaran

Turbulence mitigation (TM) is highly ill-posed due to the stochastic nature of atmospheric turbulence. Most methods rely on multiple frames recorded by conventional cameras to capture stable patterns in natural scenarios. However, they…

Computer Vision and Pattern Recognition · Computer Science 2026-03-24 Xiaoran Zhang , Jian Ding , Yuxing Duan , Haoyue Liu , Gang Chen , Yi Chang , Luxin Yan

Electron tomography is becoming an increasingly important tool in materials science for studying the three-dimensional morphologies and chemical compositions of nanostructures. The image quality obtained by many current algorithms is…

We consider the problem of reconstructing a 3-D scene from a moving camera with high frame rate using the affine projection model. This problem is traditionally known as Affine Structure from Motion (Affine SfM), and can be solved using an…

Computer Vision and Pattern Recognition · Computer Science 2016-08-10 Roberto Tron

The influence of atmospheric turbulence on acquired imagery makes image interpretation and scene analysis extremely difficult and reduces the effectiveness of conventional approaches for classifying and tracking objects of interest in the…

Computer Vision and Pattern Recognition · Computer Science 2024-09-24 Paul Hill , Nantheera Anantrasirichai , Alin Achim , David Bull

Several site-testing programs and observatories currently use combined MASS-DIMM instruments for monitoring parameters of optical turbulence. The instrument is described here. After a short recall of the measured quantities and operational…

Astrophysics · Physics 2009-11-13 V. Kornilov , A. Tokovinin , N. Shatsky , O. Voziakova , S. Potanin , B. Safonov

We present a method that can be used to recover the spectrum of turbulence from observations of optically thin emission lines formed in astrophysical disks. Within this method we analyze how line intensity fluctuations depend on the angular…

Instrumentation and Methods for Astrophysics · Physics 2016-03-23 D. V. Bisikalo , E. P. Kurbatov , Ya. N. Pavlyuchenkov , A. G. Zhilkin , P. V. Kaygorodov

Recovering the 3D structure of the surrounding environment is an essential task in any vision-controlled Structure-from-Motion (SfM) scheme. This paper focuses on the theoretical properties of the SfM, known as the incremental active depth…

Robotics · Computer Science 2020-03-17 Romulo T. Rodrigues , Pedro Miraldo , Dimos V. Dimarogonas , A. Pedro Aguiar

The image reconstruction of partially coherent light is interpreted as the quantum state reconstruction. The efficient method based on maximum-likelihood estimation is proposed to acquire information from registered intensity measurements…

Optics · Physics 2011-07-22 M. Jezek , Z. Hradil