English
Related papers

Related papers: Point spread function modeling and images restorat…

200 papers

Galaxy imaging surveys observe a vast number of objects that are affected by the instrument's Point Spread Function (PSF). Weak lensing missions, in particular, aim at measuring the shape of galaxies, and PSF effects represent an important…

Instrumentation and Methods for Astrophysics · Physics 2021-02-03 T. Liaudat , J. Bonnin , J. -L. Starck , M. A. Schmitz , A. Guinot , M. Kilbinger , S. D. J. Gwyn

X-ray computed tomography (CT) reveals the materials' internal structures non-destructively from a tilt series of projected images. Filtered back projection (FBP) is a widely-adopted reconstruction algorithm in CT owing to its small…

Point spread function (PSF) engineering of the emitter can code higher spatial frequency information of an image to break diffraction limit but suffer from the complexed optical systems. Here we present a robust strategy to simultaneously…

Optics · Physics 2021-02-23 Chaohao Chen , Baolei Liu , Yongtao Liu , Jiayan Liao , Xuchen Shan , Fan Wang , Dayong Jin

The shear measurement is a crucial task in the current and the future weak lensing survey projects. And the reconstruction of the point spread function(PSF) is one of the essential steps. In this work, we present three different methods,…

Instrumentation and Methods for Astrophysics · Physics 2016-09-28 Baishun Li , Guoliang Li , Jun Cheng , John Peterson , Wei Cui

In a previous work we have demonstrated a novel numerical model for the point spread function (PSF) of an optical system that can efficiently model both experimental measurements and lens design simulations of the PSF. The novelty lies in…

Image and Video Processing · Electrical Eng. & Systems 2018-06-25 Matthias Lehmann , Christian Wittpahl , Hatem Ben Zakour , Alexander Braun

Point-spread-function (PSF) engineering is a well-established computational imaging technique that uses phase masks and other optical elements to embed extra information (e.g., depth) into the images captured by conventional CMOS image…

Computer Vision and Pattern Recognition · Computer Science 2024-06-14 Sachin Shah , Matthew Albert Chan , Haoming Cai , Jingxi Chen , Sakshum Kulshrestha , Chahat Deep Singh , Yiannis Aloimonos , Christopher Metzler

X-ray Computed Tomography (CT) imaging has been widely used in clinical diagnosis, non-destructive examination, and public safety inspection. Sparse-view (sparse view) CT has great potential in radiation dose reduction and scan…

Medical Physics · Physics 2019-05-29 Kaichao Liang , Hongkai Yang , Yuxiang Xing

Modern Giant Segmented Mirror Telescopes (GSMTs) like the Extremely Large Telescope, which is currently under construction, depend heavily on Adaptive Optics (AO) systems to correct for atmospheric distortions. However, a residual blur…

Instrumentation and Methods for Astrophysics · Physics 2023-07-05 Roland Wagner , Jenny Niebsch , Ronny Ramlau

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 order to improve image quality of projection in industrial applications, generally, a standard method is to increase the current or exposure time, which might cause overexposure of detector units in areas of thin objects or backgrounds.…

Image and Video Processing · Electrical Eng. & Systems 2024-12-10 Mengyu Sun , Dimeng Xia , Shusen Zhao , Weibin Zhang , Yaobin He

Computed tomography is a method for synthesizing volumetric or cross-sectional images of an object from a collection of projections. Popular reconstruction methods for computed tomography are based on idealized models and assumptions that…

Numerical Analysis · Mathematics 2022-03-03 Frederik H. Pedersen , Jakob S. Jørgensen , Martin S. Andersen

Spectral computed tomography (CT) is an emerging technology capable of providing high chemical specificity, which is crucial for many applications such as detecting threats in luggage. This type of application requires both fast and…

Image and Video Processing · Electrical Eng. & Systems 2021-03-30 Wail Mustafa , Christian Kehl , Ulrik Lund Olsen , Søren Kimmer Schou Gregersen , David Malmgren-Hansen , Jan Kehres , Anders Bjorholm Dahl

For single source helical Computed Tomography (CT), both Filtered-Back Projection (FBP) and statistical iterative reconstruction have been investigated. However for dual source CT with flying focal spot (DS-FFS CT), statistical iterative…

Image and Video Processing · Electrical Eng. & Systems 2022-02-14 Xiao Wang , Robert D. MacDougall , Peng Chen , Charles A. Bouman , Simon K. Warfield

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

Intraoperative CT imaging serves as a crucial resource for surgical guidance; however, it may not always be readily accessible or practical to implement. In scenarios where CT imaging is not an option, reconstructing CT scans from X-rays…

Image and Video Processing · Electrical Eng. & Systems 2024-08-22 Zhi Qiao , Xuhui Liu , Xiaopeng Wang , Runkun Liu , Xiantong Zhen , Pei Dong , Zhen Qian

PET super-resolution is highly under-constrained because paired multi-resolution scans from the same subject are rarely available, and effective resolution is determined by scanner-specific physics (e.g., PSF, detector geometry, and…

Computer Vision and Pattern Recognition · Computer Science 2026-03-17 Liutao Yang , Zi Wang , Peiyuan Jing , Xiaowen Wang , Javier A. Montoya-Zegarra , Kuangyu Shi , Daoqiang Zhang , Guang Yang

Image-generative artificial intelligence (AI) has garnered significant attention in recent years. In particular, the diffusion model, a core component of generative AI, produces high-quality images with rich diversity. In this study, we…

Computer Vision and Pattern Recognition · Computer Science 2024-09-13 Sho Ozaki , Shizuo Kaji , Toshikazu Imae , Kanabu Nawa , Hideomi Yamashita , Keiichi Nakagawa

Diffusion-based sparse-view CT (SVCT) imaging has achieved remarkable advancements in recent years, thanks to its more stable generative capability. However, recovering reliable image content and visually consistent textures is still a…

Computer Vision and Pattern Recognition · Computer Science 2026-04-14 Tianqi Wang , Wenchao Du , Hongyu Yang

Scanning Kelvin probe microscopy (SKPM) is a powerful technique for investigating the electrostatic properties of material surfaces, enabling the imaging of variations in work function, topology, surface charge density, or combinations…

Applied Physics · Physics 2024-07-26 Isaac C. D. Lenton , Felix Pertl , Lubuna Shafeek , Scott R. Waitukaitis

Traditional dictionary learning based CT reconstruction methods are patch-based and the features learned with these methods often contain shifted versions of the same features. To deal with these problems, the convolutional sparse coding…

Medical Physics · Physics 2018-10-16 Peng Bao , Wenjun Xia , Kang Yang , Jiliu Zhou , Yi Zhang