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Related papers: A novel two- and multi-level binary phase mask des…

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Despite significant advances in Deep Face Recognition (DFR) systems, introducing new DFRs under specific constraints such as varying pose still remains a big challenge. Most particularly, due to the 3D nature of a human head, facial…

Computer Vision and Pattern Recognition · Computer Science 2020-01-23 Sara Shahsavarani , Morteza Analoui , Reza Shoja Ghiass

Ultra-Wide-Field Fluorescein Angiography (UWF-FA) enables precise identification of ocular diseases using sodium fluorescein, which can be potentially harmful. Existing research has developed methods to generate UWF-FA from Ultra-Wide-Field…

Computer Vision and Pattern Recognition · Computer Science 2024-09-04 Zhaojie Fang , Xiao Yu , Guanyu Zhou , Ke Zhuang , Yifei Chen , Ruiquan Ge , Changmiao Wang , Gangyong Jia , Qing Wu , Juan Ye , Maimaiti Nuliqiman , Peifang Xu , Ahmed Elazab

Depth-from-Focus (DFF) enables precise depth estimation by analyzing focus cues across a stack of images captured at varying focal lengths. While recent learning-based approaches have advanced this field, they often struggle in complex…

Computer Vision and Pattern Recognition · Computer Science 2025-09-29 Sungmin Woo , Sangyoun Lee

We present a method to combine two periodic lattice wave-fields to generate a complex dual lattice wave-field which could be employed for microfabrication of corresponding 2D dual lattice structures. Since the addition of two periodic…

Optics · Physics 2015-10-20 Manish Kumar , Joby Joseph

Multi-view learning has become a popular research topic in recent years, but research on the cross-application of classic multi-label classification and multi-view learning is still in its early stages. In this paper, we focus on the…

Computer Vision and Pattern Recognition · Computer Science 2024-04-29 Chengliang Liu , Jie Wen , Yabo Liu , Chao Huang , Zhihao Wu , Xiaoling Luo , Yong Xu

High contrast coronagraphic imaging of the immediate surrounding of stars requires exquisite control of low-order wavefront aberrations, such as tip-tilt (pointing) and focus. We propose an accurate, efficient and easy to implement…

Instrumentation and Methods for Astrophysics · Physics 2011-02-11 Olivier Guyon , Taro Matsuo , Roger Angel

Ultrasound imaging is widely used in noninvasive medical diagnostics due to its efficiency, portability, and avoidance of ionizing radiation. However, its utility is limited by the quality of the signal. Signal-dependent speckle noise,…

Image and Video Processing · Electrical Eng. & Systems 2026-02-10 Soumee Guha , Scott T. Acton

A simple imaging system together with complex semidefinite programming is used to generate the transmission matrix of a multimode fiber. Once the transmission matrix is acquired, we can modulate the phase of the input signal to induce…

In this paper, a novel method to enhance Frequency Modulated Continuous Wave (FMCW) THz imaging resolution beyond its diffraction limit is proposed. Our method comprises two stages. Firstly, we reconstruct the signal in depth-direction…

Image and Video Processing · Electrical Eng. & Systems 2019-07-03 Tak Ming Wong , Matthias Kahl , Peter Haring Bolívar , Andreas Kolb

Context. Solar wavefront sensing has been a challenge for astrophysical instrumentalists, due to the low contrast between the Sun and the sky background compared to night-time observations, which limits the performance of adaptive optics…

Wave-front sensing from focal plane multiple images is a promising technique for high-contrast imaging systems. However, the wave-front error of an optics system can be properly reconstructed only when it is very small. This paper presents…

Instrumentation and Methods for Astrophysics · Physics 2015-05-19 Jiangpei Dou , Deqing Ren , Yongtian Zhu

Phase retrieval with pre-defined optical masks can provide extra constraint and thus achieve improved performance. The recent progress in optimization theory demonstrates the superiority of random masks in phase retrieval algorithms.…

Image and Video Processing · Electrical Eng. & Systems 2022-07-27 Qiuliang Ye , Yuk-Hee Chan , Michael G. Somekh , Daniel P. K. Lun

Camouflaged objects are typically assimilated into their backgrounds and exhibit fuzzy boundaries. The complex environmental conditions and the high intrinsic similarity between camouflaged targets and their surroundings pose significant…

Computer Vision and Pattern Recognition · Computer Science 2023-06-07 Tianyou Chen , Jin Xiao , Xiaoguang Hu , Guofeng Zhang , Shaojie Wang

The family of multi-plane phase retrieval sensors, such as the curvature and nonlinear curvature wavefront sensors (WFS), contain tip/tilt information embedded in their signals. We have built a nonlinear curvature WFS to study different…

Instrumentation and Methods for Astrophysics · Physics 2026-03-12 Caleb G. Abbott , Justin R. Crepp , Brian Sands

Recently, a method of recording holograms of coherently illuminated three-dimensional scene without two-wave interference was demonstrated. The method is an extension of the coded aperture correlation holography from incoherent to coherent…

Optics · Physics 2023-07-19 Nathaniel Hai , Joseph Rosen

The design of a complex phase mask (CPM) for inscribing aperiodic filters in fibers is presented. The complex structure of the mask surface relief consists of discrete aperiodic phase-steps at periodic intervals. We show that the…

Instrumentation and Methods for Astrophysics · Physics 2020-04-21 Aashia Rahman , Kalaga Madhav , Martin M. Roth

Surveillance and security scenarios usually require high efficient facial image compression scheme for face recognition and identification. While either traditional general image codecs or special facial image compression schemes only…

Multimedia · Computer Science 2019-03-08 Zhibo Chen , Tianyu He

For astronomical instruments, accurate knowledge of the optical pointing and coupling are essential to characterize the alignment and performance of (sub-)systems prior to integration and deployment. Ideally, this requires the phase…

Instrumentation and Methods for Astrophysics · Physics 2020-02-11 S. J. C. Yates , K. K. Davis , W. Jellema , J. J. A. Baselmans , A. M. Baryshev

In this paper, we derive a new class of methods for the classic 2D phase unwrapping problem of recovering a phase function from its wrapped form. For this, we consider the wrapped phase as a wavefront aberration in an optical system, and…

Numerical Analysis · Mathematics 2025-03-14 Simon Hubmer , Victoria Laidlaw , Ronny Ramlau , Ekaterina Sherina , Bernadett Stadler

Dielectric metasurfaces provide a unique platform for efficient harmonic generation and optical wavefront manipulation at the nanoscale. Tailoring phase and amplitude of a nonlinearly generated wave with a high emission efficiency using…

Optics · Physics 2022-10-03 David Hähnel , Jens Förstner , Viktor Myroshnychenko