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We consider a phase retrieval problem, where we want to reconstruct a $n$-dimensional vector from its phaseless scalar products with $m$ sensing vectors. We assume the sensing vectors to be independently sampled from complex normal…

Statistics Theory · Mathematics 2016-09-13 Irène Waldspurger

The main objective of this paper is to find algorithms accompanied by explicit error bounds for phase retrieval from noisy magnitudes of frame coefficients when the underlying frame has a low redundancy. We achieve these goals with frames…

Functional Analysis · Mathematics 2014-12-23 Bernhard G. Bodmann , Nathaniel Hammen

In conventional tomographic reconstruction, the pre-processing step includes flat-field correction, where each sample projection on the detector is divided by a reference image taken without the sample. When using coherent X-rays as probe,…

Image and Video Processing · Electrical Eng. & Systems 2024-10-24 Viktor Nikitin , Marcus Carlsson , Doga Gursoy , Rajmund Mokso , Peter Cloetens

Ptychography is a powerful imaging technique that is used in a variety of fields, including materials science, biology, and nanotechnology. However, the accuracy of the reconstructed ptychography image is highly dependent on the accuracy of…

Applied Physics · Physics 2024-06-03 Ming Du , Tao Zhou , Junjing Deng , Daniel J. Ching , Steven Henke , Mathew J. Cherukara

Neural Architecture Search (NAS) aims to facilitate the design of deep networks for new tasks. Existing techniques rely on two stages: searching over the architecture space and validating the best architecture. NAS algorithms are currently…

Machine Learning · Computer Science 2019-11-25 Kaicheng Yu , Christian Sciuto , Martin Jaggi , Claudiu Musat , Mathieu Salzmann

Digital fringe projection (DFP) enables micrometer-level 3D reconstruction, yet extending it to large-scale mapping remains challenging because six-degree-of-freedom pose estimation often cannot match the reconstruction's precision.…

Computer Vision and Pattern Recognition · Computer Science 2026-03-13 Sehoon Tak , Keunhee Cho , Sangpil Kim , Jae-Sang Hyun

Phase retrieval (PR) concerns the recovery of complex phases from complex magnitudes. We identify the connection between the difficulty level and the number and variety of symmetries in PR problems. We focus on the most difficult far-field…

Computer Vision and Pattern Recognition · Computer Science 2022-11-03 Zhong Zhuang , David Yang , Felix Hofmann , David Barmherzig , Ju Sun

Existing deep learning-based hyperspectral image (HSI) classification works still suffer from the limitation of the fixed-sized receptive field, leading to difficulties in distinctive spectral-spatial features for ground objects with…

Computer Vision and Pattern Recognition · Computer Science 2023-02-24 Lin Zhan , Jiayuan Fan , Peng Ye , Jianjian Cao

In this paper we tackle the problem of recovering the phase of complex linear measurements when only magnitude information is available and we control the input. We are motivated by the recent development of dedicated optics-based hardware…

Machine Learning · Computer Science 2020-02-17 Sidharth Gupta , Rémi Gribonval , Laurent Daudet , Ivan Dokmanić

Majority of the current dimensionality reduction or retrieval techniques rely on embedding the learned feature representations onto a computable metric space. Once the learned features are mapped, a distance metric aids the bridging of gaps…

Computer Vision and Pattern Recognition · Computer Science 2018-10-17 Muhammad Kamran Janjua , Shah Nawaz , Alessandro Calefati , Ignazio Gallo

We propose a flexible convex relaxation for the phase retrieval problem that operates in the natural domain of the signal. Therefore, we avoid the prohibitive computational cost associated with "lifting" and semidefinite programming (SDP)…

Information Theory · Computer Science 2017-03-17 Sohail Bahmani , Justin Romberg

Several strategies in phase retrieval are unified by an iterative "difference map" constructed from a pair of elementary projections and a single real parameter $\beta$. For the standard application in optics, where the two projections…

Numerical Analysis · Mathematics 2025-10-20 Veit Elser

A standardized phase retrieval algorithm is presented and applied to an industry-grade high-energy ultrashort pulsed laser to uncover its spatial phase distribution. We describe in detail how to modify the well-known algorithm in order to…

Phase retrieval is a problem encountered not only in speech and audio processing, but in many other fields such as optics. Iterative algorithms based on non-convex set projections are effective and frequently used for retrieving the phase…

Audio and Speech Processing · Electrical Eng. & Systems 2022-11-10 Tal Peer , Simon Welker , Timo Gerkmann

A new algorithmic framework is presented for holographic phase retrieval via maximum likelihood optimization, which allows for practical and robust image reconstruction. This framework is especially well-suited for holographic coherent…

Image and Video Processing · Electrical Eng. & Systems 2022-02-18 David A. Barmherzig , Ju Sun

We present a retrieval algorithm based on generalized projections for ultrashort pulse characterization using dispersion scan (d-scan). The new algorithm is tested on several simulated cases and in two different experimental cases in the…

Phase retrieval, the problem of recovering lost phase information from measured intensity alone, is an inverse problem that is widely faced in various imaging modalities ranging from astronomy to nanoscale imaging. The current process of…

Image and Video Processing · Electrical Eng. & Systems 2024-06-12 Henry Chan , Youssef S. G. Nashed , Saugat Kandel , Stephan Hruszkewycz , Subramanian Sankaranarayanan , Ross J. Harder , Mathew J. Cherukara

Phase retrieval is a nonlinear inverse problem that arises in a wide range of imaging modalities, from electron microscopy to Fourier ptychography. In particular, the reconstruction is facilitated when the sensing matrix is i.i.d. random,…

We present a convex relaxation-based algorithm for large-scale general phase retrieval problems. General phase retrieval problems include i.a. the estimation of the phase of the optical field in the pupil plane based on intensity…

Optimization and Control · Mathematics 2018-08-15 Reinier Doelman , H. Thao Nguyen , Michel Verhaegen

In this paper, we develop a novel phase retrieval approach to reconstruct x-ray differential phase shift induced by an object. A primary advantage of our approach is a higher-order accuracy over that with the conventional linear…

Medical Physics · Physics 2010-03-18 Wenxiang Cong , Ge Wang