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Vision encoders are increasingly used in modern applications, from vision-only models to multimodal systems such as vision-language models. Despite their remarkable success, it remains unclear how these architectures represent features…

Computer Vision and Pattern Recognition · Computer Science 2025-06-10 Eduard Allakhverdov , Dmitrii Tarasov , Elizaveta Goncharova , Andrey Kuznetsov

Generating multi-contrasts/modal MRI of the same anatomy enriches diagnostic information but is limited in practice due to excessive data acquisition time. In this paper, we propose a novel deep-learning model for joint reconstruction and…

Image and Video Processing · Electrical Eng. & Systems 2022-06-30 Wanyu Bian , Qingchao Zhang , Xiaojing Ye , Yunmei Chen

This dissertation is devoted to provide advanced nonconvex nonsmooth variational models of (Magnetic Resonance Image) MRI reconstruction, efficient learnable image reconstruction algorithms and parameter training algorithms that improve the…

Optimization and Control · Mathematics 2023-03-06 Wanyu Bian

We consider the problem of learning error covariance matrices for robotic state estimation. The convergence of a state estimator to the correct belief over the robot state is dependent on the proper tuning of noise models. During inference,…

Robotics · Computer Science 2023-09-19 Mohamad Qadri , Zachary Manchester , Michael Kaess

Following the success of deep learning in a wide range of applications, neural network-based machine learning techniques have received interest as a means of accelerating magnetic resonance imaging (MRI). A number of ideas inspired by deep…

Signal Processing · Electrical Eng. & Systems 2019-04-03 Florian Knoll , Kerstin Hammernik , Chi Zhang , Steen Moeller , Thomas Pock , Daniel K. Sodickson , Mehmet Akcakaya

We propose techniques for approximating bilevel optimization problems with non-smooth lower level problems that can have a non-unique solution. To this end, we substitute the expression of a minimizer of the lower level minimization problem…

Optimization and Control · Mathematics 2016-04-27 Peter Ochs , René Ranftl , Thomas Brox , Thomas Pock

Nowadays, due to advanced digital imaging technologies and internet accessibility to the public, the number of generated digital images has increased dramatically. Thus, the need for automatic image enhancement techniques is quite apparent.…

Image and Video Processing · Electrical Eng. & Systems 2021-12-08 Saeedeh Rezaee , Nezam Mahdavi-Amiri

Image rescaling is a commonly used bidirectional operation, which first downscales high-resolution images to fit various display screens or to be storage- and bandwidth-friendly, and afterward upscales the corresponding low-resolution…

Image and Video Processing · Electrical Eng. & Systems 2022-10-11 Mingqing Xiao , Shuxin Zheng , Chang Liu , Zhouchen Lin , Tie-Yan Liu

Deep neural networks have become a foundational tool for addressing imaging inverse problems. They are typically trained for a specific task, with a supervised loss to learn a mapping from the observations to the image to recover. However,…

Computer Vision and Pattern Recognition · Computer Science 2023-12-01 Matthieu Terris , Thomas Moreau

The field of medical image reconstruction has seen roughly four types of methods. The first type tended to be analytical methods, such as filtered back-projection (FBP) for X-ray computed tomography (CT) and the inverse Fourier transform…

Image and Video Processing · Electrical Eng. & Systems 2019-08-19 Saiprasad Ravishankar , Jong Chul Ye , Jeffrey A. Fessler

Constrained bilevel optimization tackles nested structures present in constrained learning tasks like constrained meta-learning, adversarial learning, and distributed bilevel optimization. However, existing bilevel optimization methods…

Optimization and Control · Mathematics 2024-06-05 Wei Yao , Haian Yin , Shangzhi Zeng , Jin Zhang

Models initialized from self-supervised pretraining may suffer from poor alignment with downstream tasks, reducing the extent to which subsequent fine-tuning can adapt pretrained features toward downstream objectives. To mitigate this, we…

Machine Learning · Computer Science 2026-02-11 Gustav Wagner Zakarias , Lars Kai Hansen , Zheng-Hua Tan

Underwater images are degraded by the selective attenuation of light that distorts colours and reduces contrast. The degradation extent depends on the water type, the distance between an object and the camera, and the depth under the water…

Computer Vision and Pattern Recognition · Computer Science 2020-12-23 Chau Yi Li , Riccardo Mazzon , Andrea Cavallaro

The challenges in recovering underwater images are the presence of diverse degradation factors and the lack of ground truth images. Although synthetic underwater image pairs can be used to overcome the problem of inadequately observing…

Computer Vision and Pattern Recognition · Computer Science 2023-03-14 Zhenwei Zhang , Haorui Yan , Ke Tang , Yuping Duan

In the last years, the design of image reconstruction methods in the field of quantitative Magnetic Resonance Imaging (qMRI) has experienced a paradigm shift. Often, when dealing with (quantitative) MR image reconstruction problems, one is…

Optimization and Control · Mathematics 2024-03-01 Andreas Kofler , Felix Frederik Zimmermann , Kostas Papafitsoros

Magnetic Particle Imaging (MPI) is a recent imaging modality where superparamagnetic nanoparticles are employed as tracers. The reconstruction task is to obtain the spatial particle distribution from a voltage signal induced by the…

Numerical Analysis · Mathematics 2025-08-11 Thomas März , Vladyslav Gapyak , Andreas Weinmann

Photoelastic techniques have a long tradition in both qualitative and quantitative analysis of the stresses in granular materials. Over the last two decades, computational methods for reconstructing forces between particles from their…

Computer Vision and Pattern Recognition · Computer Science 2021-08-04 Renat Sergazinov , Miroslav Kramar

Low-rank structures play important role in recent advances of many problems in image science and data science. As a natural extension of low-rank structures for data with nonlinear structures, the concept of the low-dimensional manifold…

Computer Vision and Pattern Recognition · Computer Science 2017-02-10 Rongjie Lai , Jia Li

Magnetic resonance imaging (MRI) reconstruction is a fundamental task aimed at recovering high-quality images from undersampled or low-quality MRI data. This process enhances diagnostic accuracy and optimizes clinical applications. In…

Image and Video Processing · Electrical Eng. & Systems 2025-03-11 Xiaoyan Kui , Zijie Fan , Zexin Ji , Qinsong Li , Chengtao Liu , Weixin Si , Beiji Zou

Almost every single image restoration problem has a closely related parameter, such as the scale factor in super-resolution, the noise level in image denoising, and the quality factor in JPEG deblocking. Although recent studies on image…

Image and Video Processing · Electrical Eng. & Systems 2021-11-02 Fangzhou Luo , Xiaolin Wu , Yanhui Guo