English
Related papers

Related papers: Optical Distortion in the NACO Imager

200 papers

This paper proposes an automatic image correction method for portrait photographs, which promotes consistency of facial skin color by suppressing skin color changes due to background colors. In portrait photographs, skin color is often…

Graphics · Computer Science 2026-05-21 Keiichiro Shirai , Tatsuya Baba , Shunsuke Ono , Masahiro Okuda , Yusuke Tatesumi , Paul Perrotin

High quality imaging usually requires bulky and expensive lenses to compensate geometric and chromatic aberrations. This poses high constraints on the optical hash or low cost applications. Although one can utilize algorithmic…

Image and Video Processing · Electrical Eng. & Systems 2021-08-20 Xiu Li , Jinli Suo , Weihang Zhang , Xin Yuan , Qionghai Dai

Underwater optical imaging is severely degraded by light absorption, scattering, and color distortion, hindering visibility and accurate image analysis. This paper presents an adaptive enhancement framework integrating illumination…

Computer Vision and Pattern Recognition · Computer Science 2025-03-06 Yuezhe Tian , Kangchen Yao , Xiaoyang Yu

We present new data processing techniques that allow to correct the main instrumental effects that degrade the images obtained by ISOCAM, the camera on board the Infrared Space Observatory (ISO). Our techniques take advantage of the fact…

Astrophysics · Physics 2009-10-31 M. -A. Miville-Deschenes , F. Boulanger , A. Abergel , J. -P. Bernard

Sensing light's polarization and wavefront direction enables surface curvature assessment, material identification, shadow differentiation, and improved image quality in turbid environments. Traditional polarization cameras utilize multiple…

We propose a method for optical nano-imaging in which the structure of a three-dimensional inhomogeneous medium may be recovered from far-field power measurements. Neither phase control of the illuminating field nor phase measurements of…

Mesoscale and Nanoscale Physics · Physics 2017-02-02 Alexander A. Govyadinov , George Y. Panasyuk , John C. Schotland

This paper proposes a novel approach to image deblurring and digital zooming using sparse local models of image appearance. These models, where small image patches are represented as linear combinations of a few elements drawn from some…

Machine Learning · Computer Science 2011-10-07 Florent Couzinie-Devy , Julien Mairal , Francis Bach , Jean Ponce

When inverting solar spectra, image degradation effects that are present in the data are usually approximated or not considered. We develop a data reduction method that takes these issues into account and minimizes the resulting errors. By…

Instrumentation and Methods for Astrophysics · Physics 2015-06-11 M. van Noort

In a previous article concerning image distortion in non-perturbative gravitational lensing theory we described how to introduce shape and distortion parameters for small sources. We also showed how they could be expressed in terms of the…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Simonetta Frittelli , Thomas P. Kling , Ezra T. Newman

Diffractive lenses have recently been applied to the domain of multispectral imaging in the X-ray and UV regimes where they can achieve very high resolution as compared to reflective and refractive optics. Conventionally, spectral…

Image and Video Processing · Electrical Eng. & Systems 2020-05-26 Evan Widloski , Ulas Kamaci , Farzad Kamalabadi

Background: Magnetic field inhomogeneities generate important geometric distortions in reconstructed echo-planar images. Various procedures were proposed for correcting these distortions on brain images; yet, few neuroimaging studies…

Image and Video Processing · Electrical Eng. & Systems 2021-08-10 Haykel Snoussi , Julien Cohen-Adad , Olivier Commowick , Benoit Combes , Elise Bannier , Soizic Leguy , Anne Kerbrat , Christian Barillot , Emmanuel Caruyer

Plastic scintillation detectors are increasingly used to measure dose distributions in the context of radiotherapy treatments. Their water-equivalence, real-time response and high spatial resolution distinguish them from traditional…

Medical Physics · Physics 2021-09-22 Emily Cloutier , Louis Archambault , Luc Beaulieu

Distortion rectification is often required for fisheye images. The generation-based method is one mainstream solution due to its label-free property, but its naive skip-connection and overburdened decoder will cause blur and incomplete…

Computer Vision and Pattern Recognition · Computer Science 2021-04-01 Shangrong Yang , Chunyu Lin , Kang Liao , Chunjie Zhang , Yao Zhao

In this paper, we consider subaperture-based approaches for the digital aberration correction (DAC) of optical coherence tomography (OCT) images. In particular, we introduce a mathematical framework for describing this class of approaches,…

Each image acquisition setup leads to its own camera-specific image characteristics degrading the image quality. In learning-based perception algorithms, characteristics occurring during the application phase, but absent in the training…

Image and Video Processing · Electrical Eng. & Systems 2026-02-26 Maximiliane Gruber , Jürgen Seiler , André Kaup

This paper proposes a non-computational method of counteracting the effect of image degradation introduced by the diffraction phenomenon in lensless microscopy. All the optical images (whether focused by lenses or not) are diffraction…

Optics · Physics 2021-04-08 Sanjeev Kumar , Manjunatha Mahadevappa , Pranab Kumar Dutta

The problem of noise in a general data acquisition procedure can be resolved more accurately if it is based on a model that describes well the distortions of the data including both spatial and intensity changes. The focus of this article…

Numerical Analysis · Mathematics 2024-12-24 Benjamin Berkels , Peter Binev

Spatiotemporal optical coherence (STOC) imaging is a new technique for suppressing coherent crosstalk noise in Fourier-domain full-field optical coherence tomography (FD-FF-OCT). In STOC imaging, the timevarying inhomogeneous phase masks…

Precise beam based measurement and correction of magnetic optics is essential for the successful operation of accelerators. The LOCO algorithm is a proven and reliable tool, which in some situations can be improved by using a broader class…

We investigate methods to calibrate the non-common path aberrations at an adaptive optics system having a wavefront-correcting device working at an extremely high resolution (larger than 150x150). We use focal-plane images collected…

Instrumentation and Methods for Astrophysics · Physics 2015-06-22 Visa Korkiakoski , Christoph U. Keller , Niek Doelman , Matthew Kenworthy , Gilles Otten , Michel Verhaegen