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Related papers: TV-regularized CT Reconstruction and Metal Artifac…

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This paper concerns iterative reconstruction for low-dose and few-view CT by minimizing a data-fidelity term regularized with the Total Variation (TV) penalty. We propose a very fast iterative algorithm to solve this problem. The algorithm…

Medical Physics · Physics 2017-02-01 Hiroyuki Kudo , Fukashi Yamazaki , Takuya Nemoto , Keita Takaki

This paper considers the constrained total variation (TV) denoising problem for complex-valued images. We extend the definition of TV seminorms for real-valued images to dealing with complex-valued ones. In particular, we introduce two…

Image and Video Processing · Electrical Eng. & Systems 2021-09-14 Yunhui Gao , Liangcai Cao

One of the fundamental assumptions of compressive sensing (CS) is that a signal can be reconstructed from a small number of samples by solving an optimization problem with the appropriate regularization term. Two standard regularization…

Image and Video Processing · Electrical Eng. & Systems 2019-06-26 Elin Farnell , Henry Kvinge , Julia R. Dupuis , Michael Kirby , Chris Peterson , Elizabeth C. Schundler

Spectral Computed Tomography (CT) is an emerging technology that enables to estimate the concentration of basis materials within a scanned object by exploiting different photon energy spectra. In this work, we aim at efficiently solving a…

Optimization and Control · Mathematics 2021-03-26 Alessandro Perelli , Martin S. Andersen

In this paper, a variational, multi-dimensional model for image reconstruction is proposed, in which the regularization term consists of the $r$-order (an)-isotropic total variation seminorms $TV^r$, with $r\in \mathbb R^+$, defined via the…

Analysis of PDEs · Mathematics 2019-01-17 Pan Liu , Xin Yang Lu

Metal artifact reduction (MAR) is a challenging problem in computed tomography (CT) imaging. A popular class of MAR methods replace sinogram measurements that are corrupted by metal with artificial data. While these ``projection…

Medical Physics · Physics 2021-01-27 T. Humphries , J. Wang

Ring artifacts in computed tomography images, arising from the undesirable responses of detector units, significantly degrade image quality and diagnostic reliability. To address this challenge, we propose a dual-domain regularization model…

Image and Video Processing · Electrical Eng. & Systems 2024-03-18 Hongyang Zhu , Xin Lu , Yanwei Qin , Xinran Yu , Tianjiao Sun , Yunsong Zhao

X-ray computed tomography (CT) is widely utilized in the medical, industrial, and other fields to nondestructively generate three-dimensional structural images of objects. However, CT images are often affected by various artifacts, with…

Medical Physics · Physics 2025-05-27 Yang Zou , Meili Qi , Jianhua Zhang , Difei Zhang , Shuwei Wang , Jiale Zhang , Shengkun Yao , Huaidong Jiang

Purpose: We develop an iterative image-reconstruction algorithm for application to low-intensity computed tomography (CT) projection data, which is based on constrained, total-variation (TV) minimization. The algorithm design focuses on…

Medical Physics · Physics 2015-05-20 Emil Y. Sidky , Yuval Duchin , Christer Ullberg , Xiaochuan Pan

A conventional approach to computed tomography (CT) or cone beam CT (CBCT) metal artifact reduction is to replace the X-ray projection data within the metal trace with synthesized data. However, existing projection or sinogram completion…

Image and Video Processing · Electrical Eng. & Systems 2022-03-24 Haofu Liao , Wei-An Lin , Zhimin Huo , Levon Vogelsang , William J. Sehnert , S. Kevin Zhou , Jiebo Luo

We propose a second-order total generalized variation (TGV) regularization for the reconstruction of the initial condition in variational data assimilation problems. After showing the equivalence between TGV regularization and the Bayesian…

Optimization and Control · Mathematics 2018-04-13 J. C. De los Reyes , E. Loayza

In this work, we introduce a function space setting for a wide class of structural/weighted total variation (TV) regularization methods motivated by their applications in inverse problems. In particular, we consider a regularizer that is…

Optimization and Control · Mathematics 2018-05-23 Michael Hintermüller , Martin Holler , Kostas Papafitsoros

Metal objects pose a significant challenge in cone-beam computed tomography, as their strong and energy-dependent X-ray attenuation leads to inconsistent projections and severe streaking and shading artifacts in reconstructed images. These…

In this paper, a new regularization term is proposed to solve mathematical image problems. By using difference operators in the four directions; horizontal, vertical and two diagonal directions, an estimation of derivative amplitude is…

Numerical Analysis · Mathematics 2022-09-14 Alireza Hosseini

With the development of computed tomography (CT) imaging technology, it is possible to acquire multi-energy data by spectral CT. Being different from conventional CT, the X-ray energy spectrum of spectral CT is cutting into several narrow…

Medical Physics · Physics 2023-01-25 Yuanwei He , Li Zeng , Qiong Xu , Zhe Wang , Haijun Yu , Zhaoqiang Shen , Zhaojun Yang , Rifeng Zhou

We introduce a method for fast estimation of data-adapted, spatio-temporally dependent regularization parameter-maps for variational image reconstruction, focusing on total variation (TV)-minimization. Our approach is inspired by recent…

Recently, total variation (TV) based minimization algorithms have achieved great success in compressive sensing (CS) recovery for natural images due to its virtue of preserving edges. However, the use of TV is not able to recover the fine…

Computer Vision and Pattern Recognition · Computer Science 2012-12-27 Jian Zhang , Shaohui Liu , Debin Zhao , Ruiqin Xiong , Siwei Ma

PURPOSE: We develop a practical, iterative algorithm for image-reconstruction in under-sampled tomographic systems, such as digital breast tomosynthesis (DBT). METHOD: The algorithm controls image regularity by minimizing the image total…

We consider the problem of signal reconstruction for computed tomography (CT) under a nonlinear forward model that accounts for exponential signal attenuation, a polychromatic X-ray source, general measurement noise (e.g., Poisson shot…

Image and Video Processing · Electrical Eng. & Systems 2026-02-12 Mengqi Lou , Kabir Aladin Verchand , Sara Fridovich-Keil , Ashwin Pananjady

This work considers synergistic multi-spectral CT reconstruction where information from all available energy channels is combined to improve the reconstruction of each individual channel, we propose to fuse this available data (represented…

Optimization and Control · Mathematics 2021-08-04 Evelyn Cueva , Alexander Meaney , Samuli Siltanen , Matthias J. Ehrhardt