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Related papers: Field Distortion Model Based on Fredholm Integral

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We tackle the problem of automatic calibration of radially distorted cameras in challenging conditions. Accurately determining distortion parameters typically requires either 1) solving the full Structure from Motion (SfM) problem involving…

Computer Vision and Pattern Recognition · Computer Science 2025-09-16 Daniil Sinitsyn , Linus Härenstam-Nielsen , Daniel Cremers

In current practice, scene survey is carried out by workers using total stations. The method has high accuracy, but it incurs high costs if continuous monitoring is needed. Techniques based on photogrammetry, with the relatively cheaper…

Computer Vision and Pattern Recognition · Computer Science 2021-11-11 Kwok-Leung Chan , Liping Li , Arthur Wing-Tak Leung , Ho-Yin Chan

Ultrasound is widely used in medical diagnostics allowing for accessible and powerful imaging but suffers from resolution limitations due to diffraction and the finite aperture of the imaging system, which restricts diagnostic use. The…

Computer Vision and Pattern Recognition · Computer Science 2024-08-08 Felix Duelmer , Walter Simson , Mohammad Farid Azampour , Magdalena Wysocki , Angelos Karlas , Nassir Navab

We explore the impact of aperture size and shape on automotive camera systems for deep-learning-based tasks like traffic sign recognition and light state detection. A method is proposed to simulate optical effects using the point spread…

Computer Vision and Pattern Recognition · Computer Science 2025-01-17 Ofer Bar-Shalom , Tzvi Philipp , Eran Kishon

Nonlinear lens distortion rectification is a common first step in image processing applications where the assumption of a linear camera model is essential. For rectifying the lens distortion, forward distortion model needs to be known.…

Computer Vision and Pattern Recognition · Computer Science 2017-07-05 Burak Benligiray , Cihan Topal

We present a new algorithm for estimating the Point Spread Function (PSF) in wide-field astronomical images with extreme source crowding. Robust and accurate PSF estimation in crowded astronomical images dramatically improves the fidelity…

Image and Video Processing · Electrical Eng. & Systems 2021-02-09 Brendt Wohlberg , Przemek Wozniak

Accurate modelling of the effective point spread function (ePSF) is essential for high-precision photometry and astrometry, particularly in undersampled imaging regimes. In this work, we build on a well-established ePSF modelling framework…

Instrumentation and Methods for Astrophysics · Physics 2025-12-19 Emma Godden , Katherine M. Blundell

In this work, we present a novel centroiding method based on Fourier space Phase Fitting(FPF) for Point Spread Function(PSF) reconstruction. We generate two sets of simulations to test our method. The first set is generated by GalSim with…

Instrumentation and Methods for Astrophysics · Physics 2021-07-12 Tianhuan Lu , Wentao Luo , Jun Zhang , Jiajun Zhang , Hekun Li , Fuyu Dong , Yingke Li , Dezi Liu , Liping Fu , Guoliang Li , Zuhui Fan

We study the problem of deconvolution for light-sheet microscopy, where the data is corrupted by spatially varying blur and a combination of Poisson and Gaussian noise. The spatial variation of the point spread function (PSF) of a…

A new method is presented for determining the Point Spread Function (PSF) of images that lack bright and isolated stars. It is based on the same principles as the MCS (Magain, Courbin, Sohy, 1998) image deconvolution algorithm. It uses the…

Astrophysics · Physics 2009-11-11 P. Magain , F. Courbin , M. Gillon , S. Sohy , G. Letawe , V. Chantry , Y. Letawe

In the case of ground-based telescopes equipped with adaptive optics systems, the point spread function (PSF) is only poorly known or completely unknown. Moreover, an accurate modeling of the PSF is in general not available. Therefore in…

Numerical Analysis · Mathematics 2015-06-09 M. Prato , A. La Camera , S. Bonettini , S. Rebegoldi , M. Bertero , P. Boccacci

The point-spread function (PSF) of an adaptive optics (AO) system is often poorly known. This ignorance can lead to significant systematic errors in photometry. Since the degree of AO correction is sensitive to the observing conditions:…

Astrophysics · Physics 2010-11-11 Christopher D. Sheehy , Nate McCrady , James R. Graham

In positron emission tomography (PET) imaging, statistical iterative reconstruction (IR) techniques appear particularly promising since they can provide accurate system model. The system model matrix which describes the relationship between…

The common approach to radial distortion is by the means of polynomial approximation, which introduces distortion-specific parameters into the camera model and requires estimation of these distortion parameters. The task of estimating…

Computer Vision and Pattern Recognition · Computer Science 2007-05-23 Lili Ma , YangQuan Chen , Kevin L. Moore

Optimal error estimation is key to achieve accurate photometry and astrometry. Stellar fluxes and positions in high angular resolution images are typically measured with PSF fitting routines, such as StarFinder. However, the formal…

Instrumentation and Methods for Astrophysics · Physics 2022-08-12 E. Gallego-Cano , R. Schödel , A. T. Gallego-Calvente , A. M. Ghez

This paper demonstrates a practical method that can correct spatial varying blur from a set of images of the same object. The algorithm jointly estimates the object and local point spread functions~(PSF). The method prioritizes sections…

Image and Video Processing · Electrical Eng. & Systems 2020-11-04 Wouter van de Ketterij , Oleg Soloviev , Michel Verhaegen

In astronomy, upcoming space telescopes with wide-field optical instruments have a spatially varying point spread function (PSF). Specific scientific goals require a high-fidelity estimation of the PSF at target positions where no direct…

Instrumentation and Methods for Astrophysics · Physics 2023-02-22 Tobias Liaudat , Jean-Luc Starck , Martin Kilbinger , Pierre-Antoine Frugier

We present the development of a data-driven, AI-based model of the Point Spread Function (PSF) that achieves higher accuracy than the current state-of-the-art approach, "PSF in the Full Field-of-View'' (PIFF). PIFF is widely used in leading…

Instrumentation and Methods for Astrophysics · Physics 2026-02-18 Dayana Andrea Henao Arbeláez , Pierre-François Léget , Andrés Alejandro Plazas Malagón

Optical microscopy is an essential tool in biology and medicine. Imaging thin, yet non-flat objects in a single shot (without relying on more sophisticated sectioning setups) remains challenging as the shallow depth of field that comes with…

Image and Video Processing · Electrical Eng. & Systems 2020-10-14 Adrian Shajkofci , Michael Liebling

Deblurring is a fundamental inverse problem in bioimaging. It requires modelling the point spread function (PSF), which captures the optical distortions entailed by the image formation process. The PSF limits the spatial resolution…

Image and Video Processing · Electrical Eng. & Systems 2019-03-04 Denis K. Samuylov , Prateek Purwar , Gábor Székely , Grégory Paul