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Inverse problems generally require a regularizer or prior for a good solution. A recent trend is to train a convolutional net to denoise images, and use this net as a prior when solving the inverse problem. Several proposals depend on a…

Computer Vision and Pattern Recognition · Computer Science 2023-07-12 Kyle Luther , H. Sebastian Seung

Inverse rendering seeks to estimate scene characteristics from a set of data images. The dominant approach is based on differential rendering using Monte-Carlo. Algorithms as such usually rely on a forward model and use an iterative…

Computer Vision and Pattern Recognition · Computer Science 2021-10-04 Ido Czerninski , Yoav Y. Schechner

Adaptive regularization methods pre-multiply a descent direction by a preconditioning matrix. Due to the large number of parameters of machine learning problems, full-matrix preconditioning methods are prohibitively expensive. We show how…

Machine Learning · Computer Science 2020-11-19 Naman Agarwal , Brian Bullins , Xinyi Chen , Elad Hazan , Karan Singh , Cyril Zhang , Yi Zhang

Ensembles of variational data assimilations (EDA) require solving systems of linear equations with iterative methods. The solution process can be accelerated using a limited memory preconditioner constructed with approximations of the…

Numerical Analysis · Mathematics 2026-05-25 I. Daužickaitė , S. Gürol , M. Destouches , L. Berre , A. T. Weaver

Purpose: The Unadjusted Langevin Algorithm (ULA) in combination with diffusion models can generate high quality MRI reconstructions with uncertainty estimation from highly undersampled k-space data. However, sampling methods such as…

Medical Physics · Physics 2026-05-26 Moritz Blumenthal , Tina Holliber , Jonathan I. Tamir , Martin Uecker

Dynamic surface reconstruction of objects from point cloud sequences is a challenging field in computer graphics. Existing approaches either require multiple regularization terms or extensive training data which, however, lead to…

Computer Vision and Pattern Recognition · Computer Science 2025-09-23 Julian Kaltheuner , Alexander Oebel , Hannah Droege , Patrick Stotko , Reinhard Klein

Classical iterative methods for tomographic reconstruction include the class of Algebraic Reconstruction Techniques (ART). Convergence of these stationary linear iterative methods is however notably slow. In this paper we propose the use of…

Numerical Analysis · Mathematics 2015-01-22 Siegfried Cools , Pieter Ghysels , Wim van Aarle , J. Sijbers , Wim Vanroose

Obtaining samples from the posterior distribution of inverse problems with expensive forward operators is challenging especially when the unknowns involve the strongly heterogeneous Earth. To meet these challenges, we propose a…

Machine Learning · Statistics 2021-01-12 Ali Siahkoohi , Gabrio Rizzuti , Mathias Louboutin , Philipp A. Witte , Felix J. Herrmann

Spectral image reconstruction is an important task in snapshot compressed imaging. This paper aims to propose a new end-to-end framework with iterative capabilities similar to a deep unfolding network to improve reconstruction accuracy,…

Image and Video Processing · Electrical Eng. & Systems 2023-05-09 Zeyu Cai , Jian Yu , Ziyu Zhang , Chengqian Jin , Feipeng Da

We present an approach to accelerating a wide variety of image processing operators. Our approach uses a fully-convolutional network that is trained on input-output pairs that demonstrate the operator's action. After training, the original…

Computer Vision and Pattern Recognition · Computer Science 2017-09-05 Qifeng Chen , Jia Xu , Vladlen Koltun

The bilateral and nonlocal means filters are instances of kernel-based filters that are popularly used in image processing. It was recently shown that fast and accurate bilateral filtering of grayscale images can be performed using a…

Computer Vision and Pattern Recognition · Computer Science 2019-02-20 Pravin Nair , Kunal N. Chaudhury

PET image reconstruction is challenging due to the ill-poseness of the inverse problem and limited number of detected photons. Recently deep neural networks have been widely and successfully used in computer vision tasks and attracted…

Computer Vision and Pattern Recognition · Computer Science 2017-10-11 Kuang Gong , Jiahui Guan , Kyungsang Kim , Xuezhu Zhang , Georges El Fakhri , Jinyi Qi , Quanzheng Li

Image compression and reconstruction are crucial for various digital applications. While contemporary neural compression methods achieve impressive compression rates, the adoption of such technology has been largely hindered by the…

Machine Learning · Computer Science 2025-10-06 Ethan G. Rogers , Cheng Wang

Flow-based text-to-image (T2I) models excel at prompt-driven image generation, but falter on Image Restoration (IR), often "drifting away" from being faithful to the measurement. Prior work mitigate this drift with data-specific flows or…

Image and Video Processing · Electrical Eng. & Systems 2026-05-26 Tharindu Wickremasinghe , Chenyang Qi , Harshana Weligampola , Zhengzhong Tu , Stanley H. Chan

Image reconstruction in the presence of severe degradation remains a challenging inverse problem, particularly in beam diagnostics for high-energy physics accelerators. As modern facilities demand precise detection of beam halo structures…

Computer Vision and Pattern Recognition · Computer Science 2026-03-10 Francis Osswald , Mohammed Chahbaoui , Xinyi Liang

Conditional diffusion probabilistic models can model the distribution of natural images and can generate diverse and realistic samples based on given conditions. However, oftentimes their results can be unrealistic with observable color…

Computer Vision and Pattern Recognition · Computer Science 2022-12-15 Kangfu Mei , Nithin Gopalakrishnan Nair , Vishal M. Patel

We propose an adaptive form of frameless rendering with the potential to dramatically increase rendering speed over conventional interactive rendering approaches. Without the rigid sampling patterns of framed renderers, sampling and…

Graphics · Computer Science 2025-10-21 Abhinav Dayal , Cliff Woolley , Benjamin Watson , David Luebke

Our work considers the optimization of the sum of a non-smooth convex function and a finite family of composite convex functions, each one of which is composed of a convex function and a bounded linear operator. This type of problem is…

Optimization and Control · Mathematics 2019-08-30 Yu-Chao Tang , Chuan-Xi Zhu , Meng Wen , Ji-Gen Peng

Surface reconstruction is fundamental to computer vision and graphics, enabling applications in 3D modeling, mixed reality, robotics, and more. Existing approaches based on volumetric rendering obtain promising results, but optimize on a…

Computer Vision and Pattern Recognition · Computer Science 2025-08-12 Yueh-Cheng Liu , Lukas Höllein , Matthias Nießner , Angela Dai

Score-based diffusion models achieve state-of-the-art performance for inverse problems, but their practical deployment is hindered by long inference times and cumbersome hyperparameter tuning. While pretrained diffusion models can be reused…

Computer Vision and Pattern Recognition · Computer Science 2026-05-13 Julio Oscanoa , Irmak Sivgin , Cagan Alkan , Daniel Ennis , John Pauly , Mert Pilanci , Shreyas Vasanawala