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Recovering a high-quality image from noisy indirect measurements is an important problem with many applications. For such inverse problems, supervised deep convolutional neural network (CNN)-based denoising methods have shown strong…

Image and Video Processing · Electrical Eng. & Systems 2020-09-16 Allard A. Hendriksen , Daniel M. Pelt , K. Joost Batenburg

We present a design improvement for a recently proposed type of Shack-Hartmann wavefront sensor that uses a cylindrical (lenticular) lenslet array. The improved sensor design uses optical binning and requires significantly fewer detector…

A method for estimating the axis of reflectional symmetry of an image $f(x,y)$ on the unit disc $D=\{(x,y):x^2+y^2\leq1\}$ is proposed, given that noisy data of $f(x,y)$ are observed on a discrete grid of edge width $\Delta$. Our estimation…

Applications · Statistics 2011-02-04 Nicolai Bissantz , Hajo Holzmann , Mirosław Pawlak

Recovering a low-rank signal matrix from its noisy observation, commonly known as matrix denoising, is a fundamental inverse problem in statistical signal processing. Matrix denoising methods are generally based on shrinkage or thresholding…

Methodology · Statistics 2017-01-23 Santosh Kumar Yadav , Rohit Sinha , Prabin Kumar Bora

Seismic images obtained by stacking or migration are usually characterized as low signal-to-noise ratio (SNR), low dominant frequency and sparse sampling both in depth (or time) and offset dimensions. For improving the resolution of seismic…

Geophysics · Physics 2024-08-06 Shiqi Dong , Xintong Dong , Kaiyuan Zheng , Ming Cheng , Tie Zhong , Hongzhou Wang

Haze and fog reduce the visibility of outdoor scenes as a veil like semi-transparent layer appears over the objects. As a result, images captured under such conditions lack contrast. Image dehazing methods try to alleviate this problem by…

Computer Vision and Pattern Recognition · Computer Science 2018-11-28 Shirsendu Sukanta Halder , Sanchayan Santra , Bhabatosh Chanda

Spatial mode sorting has come to prominence as an optical processing modality capable of saturating fundamental limits to numerous sensing tasks including wavefront sensing, coronagraphy, and superresolution imaging. But despite their…

Optics · Physics 2025-10-28 Jacob Trzaska , Amit Ashok

Aiming to correctly restore the redshifted 21 cm signals emitted by the neutral hydrogen during the cosmic reionization processes, we re-examine the separation approaches based on the quadratic polynomial fitting technique in frequency…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Jingying Wang , Haiguang Xu , Tao An , Junhua Gu , Xueying Guo , Weitian Li , Yu Wang , Chengze Liu , Olivier Martineau-Huynh , Xiang-Ping Wu

Zero-shot denoisers address the dataset dependency of deep-learning-based denoisers, enabling the denoising of unseen single images. Nonetheless, existing zero-shot methods suffer from long training times and rely on the assumption of noise…

Computer Vision and Pattern Recognition · Computer Science 2025-10-15 Yanlin Jiang , Yuchen Liu , Mingren Liu

Single-pixel imaging (SPI) is a potential computational imaging technique which produces image by solving an illposed reconstruction problem from few measurements captured by a single-pixel detector. Deep learning has achieved impressive…

Computer Vision and Pattern Recognition · Computer Science 2024-04-09 Gang Qu , Ping Wang , Xin Yuan

Recently, a new Signal processing method, named Semi-Classical Signal Analysis (SCSA), has been proposed for denoising Magnetic Resonance Spectroscopy (MRS) signals. It is based on the Schr\"odinger Operator's eigenspectrum. It allows an…

Signal Processing · Electrical Eng. & Systems 2019-08-22 Peihao Li , Taous Meriem Laleg-Kirati

During the last decades, denoising methods have attracted much attention of researchers. The conventional method for removing the Moire' pattern from images is using notch filters in the Frequency-domain. In this paper a new method is…

Computer Vision and Pattern Recognition · Computer Science 2017-02-01 Seyede Mahya Hazavei , Hamid Reza Shahdoosti

The classic Hartmann test consists of an array of holes to reconstruct the wavefront from the local deviation of each focal spot, and Shack-Hartmann sensor improved that with an array of microlenses. This array of microlenses imposes…

Optics · Physics 2019-12-02 Job Mendoza-Hernandez , Dorilian Lopez-Mago

Ultrasound imaging serves as an effective and non-invasive diagnostic tool commonly employed in clinical examinations. However, the presence of speckle noise in ultrasound images invariably degrades image quality, impeding the performance…

Computer Vision and Pattern Recognition · Computer Science 2023-10-06 Zhenyu Bu , Kai-Ni Wang , Fuxing Zhao , Shengxiao Li , Guang-Quan Zhou

In astronomical imaging, the low photon count of exposures necessitates extensive post-processing steps, including contamination removal and denoising. This paper evaluates deep-learning denoising methods that can be trained without clean…

Instrumentation and Methods for Astrophysics · Physics 2026-04-21 Omid Vaheb , Sebastien Fabbro , Stark Draper

Limited data and low dose constraints are common problems in a variety of tomographic reconstruction paradigms which lead to noisy and incomplete data. Over the past few years sinogram denoising has become an essential pre-processing step…

Computer Vision and Pattern Recognition · Computer Science 2016-03-15 Faisal Mahmood , Nauman Shahid , Pierre Vandergheynst , Ulf Skoglund

An important step of seismic data processing is removing noise, including interference due to simultaneous and blended sources, from the recorded data. Traditional methods are time-consuming to apply as they often require manual choosing of…

Image and Video Processing · Electrical Eng. & Systems 2019-07-03 Alan Richardson , Caelen Feller

We present a density matrix approach for treating systems with a large or infinite number of degrees of freedom per site with exact diagonalization or the density matrix renormalization group. The method is demonstrated on the 1D Holstein…

Superconductivity · Physics 2009-10-30 Chunli Zhang , Eric Jeckelmann , Steven R. White

Predictive models allow subject-specific inference when analyzing disease related alterations in neuroimaging data. Given a subject's data, inference can be made at two levels: global, i.e. identifiying condition presence for the subject,…

Computer Vision and Pattern Recognition · Computer Science 2018-07-18 Ender Konukoglu , Ben Glocker

Optical Coherence Tomography (OCT) imaging is pivotal in diagnosing ophthalmic conditions by providing detailed cross-sectional images of the anterior and posterior segments of the eye. Nonetheless, speckle noise and other imaging artifacts…

Image and Video Processing · Electrical Eng. & Systems 2024-09-26 Akkidas Noel Prakash , Jahnvi Sai Ganta , Ramaswami Krishnadas , Tin A. Tunc , Satish K Panda