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Lensless imaging is a popular research field for the advantages of small size, wide field-of-view and low aberration in recent years. However, some traditional lensless imaging methods suffer from slow convergence, mechanical errors and…

Fluorescence microscopy images usually show severe anisotropy in axial versus lateral resolution. This hampers downstream processing, i.e. the automatic extraction of quantitative biological data. While deconvolution methods and other…

Computer Vision and Pattern Recognition · Computer Science 2017-04-06 Martin Weigert , Loic Royer , Florian Jug , Gene Myers

We present a simple and effective approach for non-blind image deblurring, combining classical techniques and deep learning. In contrast to existing methods that deblur the image directly in the standard image space, we propose to perform…

Computer Vision and Pattern Recognition · Computer Science 2024-10-10 Jiangxin Dong , Stefan Roth , Bernt Schiele

We demonstrate a coherent imaging system based on a terahertz (THz) frequency quantum cascade laser (QCL) phase-locked to a near-infrared fs-laser comb. The phase locking enables coherent electro-optic sampling of the continuous-wave…

We propose a formulation of full-wavefield inversion (FWI) as a constrained optimization problem, and describe a computationally efficient technique for solving constrained full-wavefield inversion (CFWI). The technique is based on using a…

Geophysics · Physics 2014-10-28 Musa Maharramov , Biondo Biondi

We propose a new strategy for obtaining enhanced resolution (FWHM = 0.12 arcsec) deep optical images over a wide field of view. As is well known, this type of image quality can be obtained in principle simply by fast guiding on a small (D =…

Astrophysics · Physics 2009-10-31 N. Kaiser , J. L. Tonry , G. A. Luppino

Pan-Tilt-Zoom (PTZ) cameras with wide-angle lenses are widely used in surveillance but often require image rectification due to their inherent nonlinear distortions. Current deep learning approaches typically struggle to maintain…

Computer Vision and Pattern Recognition · Computer Science 2025-04-10 Teng Xiao , Qi Hu , Qingsong Yan , Wei Liu , Zhiwei Ye , Fei Deng

We present a proof-of-concept end-to-end system for computational extended depth of field (EDOF) imaging. The acquisition is performed through a phase-coded aperture implemented by placing a thin wavelength-dependent optical mask inside the…

Computer Vision and Pattern Recognition · Computer Science 2016-08-04 Tal Remez , Or Litany , Shachar Yoseff , Harel Haim , Alex Bronstein

High resolution ultrasound image reconstruction from a reduced number of measurements is of great interest in ultrasound imaging, since it could enhance both the frame rate and image resolution. Compressive deconvolution, combining…

Computer Vision and Pattern Recognition · Computer Science 2015-12-18 Zhouye Chen , Adrian Basarab , Denis Kouamé

A photonics-based leakage cancellation and echo signal de-chirping approach for frequency-modulated continuous-wave radar systems is proposed based on a dual-drive Mach-Zehnder modulator (DD-MZM), with its performance evaluated by the radar…

Signal Processing · Electrical Eng. & Systems 2022-09-21 Taixia Shi , Dingding Liang , Moxuan Han , Yang Chen

The process of acquiring microscopic images in life sciences often results in image degradation and corruption, characterised by the presence of noise and blur, which poses significant challenges in accurately analysing and interpreting the…

Computer Vision and Pattern Recognition · Computer Science 2023-07-18 Tomáš Chobola , Gesine Müller , Veit Dausmann , Anton Theileis , Jan Taucher , Jan Huisken , Tingying Peng

Real-time monitoring of dynamic biological processes in the body is critical to understanding disease progression and treatment response. This data, for instance, can help address the lower than 50% response rates to cancer immunotherapy.…

In this paper, we propose a novel method for frequency modulated continuous wave (FMCW) radar mutual interference mitigation (IM) based on the discrete fractional Fourier transform (DFrFT). Interference chirps are detected and mitigated by…

Signal Processing · Electrical Eng. & Systems 2026-04-30 Christian Oswald , Franz Pernkopf

We report the first demonstration of a 1555 nm stepped-height ridge waveguide polarization mode converter monolithically integrated with a side wall grating distributed-feedback (DFB) laser using the identical epitaxial layer scheme. The…

One of the major open problems in computer vision is detection of features in visually impaired images. In this paper, we describe a potential solution using Phase Stretch Transform, a new computational approach for image analysis, edge…

Computer Vision and Pattern Recognition · Computer Science 2017-06-16 Madhuri Suthar , Mohammad Asghari , Bahram Jalali

Frequency modulated continuous wave (FMCW) radar is emerging as a trendy radar system for synthetic aperture radar (SAR). This letter proposes a novel method for the extraction of the SAR image with the FMCW radar. The proposed method can…

Signal Processing · Electrical Eng. & Systems 2020-10-01 Junhyeong Park , Dae-Hwan Jung , Seong-Ook Park

Light scattering by tissue severely limits how deep beneath the surface one can image, and the spatial resolution one can obtain from these images. Diffuse optical tomography (DOT) is one of the most powerful techniques for imaging deep…

Image and Video Processing · Electrical Eng. & Systems 2021-05-31 Yongyi Zhao , Ankit Raghuram , Hyun K. Kim , Andreas H. Hielscher , Jacob T. Robinson , Ashok Veeraraghavan

Underwater images suffer from severe degradations, including color distortions, reduced visibility, and loss of structural details due to wavelength-dependent attenuation and scattering. Existing enhancement methods primarily focus on…

Computer Vision and Pattern Recognition · Computer Science 2025-04-15 Jaskaran Singh Walia , Shravan Venkatraman , Pavithra LK

We present the design, fabrication, and optical characterization of ultra-compact mid-wave infrared photodetector pixels. Our design relies on a guided mode resonance structure to confine incident mid-infrared light to the 250 nm-thick…

Terahertz microscopy has attracted attention owing to distinctive characteristics of the THz frequency region, particularly non-ionizing photon energy, spectral fingerprint, and transparency to most nonpolar materials. Nevertheless, the…