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Recently introduced speckle-correlations based techniques enable noninvasive imaging of objects hidden behind scattering layers. In these techniques the hidden object Fourier amplitude is retrieved from the scattered light autocorrelation,…

Optics · Physics 2022-01-19 Tengfei Wu , Ori Katz , Xiaopeng Shao , Sylvain Gigan

This work proposes a novel motion guided method for target-less self-calibration of a LiDAR and camera and use the re-projection of LiDAR points onto the image reference frame for real-time depth upsampling. The calibration parameters are…

Computer Vision and Pattern Recognition · Computer Science 2020-07-06 Juan Castorena , Gint Puskorius , Gaurav Pandey

Ptychography involves a sample being illuminated by a coherent, localised probe of illumination. When the probe interacts with the sample, the light is diffracted and a diffraction pattern is detected. Then the probe or sample is shifted…

Numerical Analysis · Mathematics 2023-05-09 Mark Philip Roach

Most current single image camera calibration methods rely on specific image features or user input, and cannot be applied to natural images captured in uncontrolled settings. We propose directly inferring camera calibration parameters from…

Computer Vision and Pattern Recognition · Computer Science 2018-04-24 Yannick Hold-Geoffroy , Kalyan Sunkavalli , Jonathan Eisenmann , Matt Fisher , Emiliano Gambaretto , Sunil Hadap , Jean-François Lalonde

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

Ptychography is a popular imaging technique that combines diffractive imaging with scanning microscopy. The technique consists of a coherent beam that is scanned across an object in a series of overlapping positions, leading to reliable and…

Numerical Analysis · Mathematics 2019-02-20 Samy Wu Fung , Zichao Di

Ptychography in a reflection geometry shows great promise for non-destructive imaging of 3-dimensional nanostructures at the surface of a thick substrate. A major challenge to obtain high quality reflection-ptychographic images under…

Generally, wave field reconstructions obtained by phase-retrieval algorithms are noisy, blurred and corrupted by various artifacts such as irregular waves, spots, etc. These disturbances, arising due to many factors such as non-idealities…

Optics · Physics 2012-07-24 Artem Migukin , Mostafa Agour , Vladimir Katkovnik

Deep neural networks have emerged as effective tools for computational imaging including quantitative phase microscopy of transparent samples. To reconstruct phase from intensity, current approaches rely on supervised learning with training…

Image and Video Processing · Electrical Eng. & Systems 2020-01-28 Emrah Bostan , Reinhard Heckel , Michael Chen , Michael Kellman , Laura Waller

Background: Tumour budding is an independent predictor of metastasis and prognosis in colorectal cancer and is a vital part of the pathology specification report. In a conventional pathological section observation process, pathologists have…

Medical Physics · Physics 2025-03-21 Yiyan Su , Ruiqing Sun , Yajing Wang , Yanfeng xi , Shaohui Zhang

Autonomy is the frontier of research in robotic surgery and its aim is to improve the quality of surgical procedures in the next future. One fundamental requirement for autonomy is advanced perception capability through vision sensors. In…

Robotics · Computer Science 2020-11-02 Andrea Roberti , Nicola Piccinelli , Daniele Meli , Riccardo Muradore , Paolo Fiorini

We address the ambiguities in the super-resolution problem under translation. We demonstrate that combinations of low-resolution images at different scales can be used to make the super-resolution problem well posed. Such differences in…

Computer Vision and Pattern Recognition · Computer Science 2026-04-24 Daniel Fu , Gabby Litterio , Pedro Felzenszwalb , Rashid Zia

X-ray ptychography is a cutting edge imaging technique providing ultra-high spatial resolutions. In ptychography, phase retrieval, i.e., the recovery of a complex valued signal from intensity-only measurements, is enabled by exploiting a…

Image and Video Processing · Electrical Eng. & Systems 2022-09-14 Felix Wittwer , Peter Modregger

In this letter, we present a novel method for automatic extrinsic calibration of high-resolution LiDARs and RGB cameras in targetless environments. Our approach does not require checkerboards but can achieve pixel-level accuracy by aligning…

Robotics · Computer Science 2021-06-28 Chongjian Yuan , Xiyuan Liu , Xiaoping Hong , Fu Zhang

A lensless digital holography enables wide-field microscopic imaging without the limitations imposed by optical lens performance. However, conventional holographic imaging often relies on magnifying optical systems to compensate for the low…

Optics · Physics 2025-06-24 Byung Gyu Chae

The optical resolution of a digital camera is one of its most crucial parameters with broad relevance for consumer electronics, surveillance systems, remote sensing, or medical imaging. However, resolution is physically limited by the…

Computer Vision and Pattern Recognition · Computer Science 2018-12-27 Thomas Köhler

We consider the problem of reconstructing one-dimensional point sources from their Fourier measurements in a bounded interval $[-\Omega, \Omega]$. This problem is known to be challenging in the regime where the spacing of the sources is…

Signal Processing · Electrical Eng. & Systems 2024-06-11 Zetao Fei , Hai Zhang

Optical aberrations prevent telescopes from reaching their theoretical diffraction limit. Once estimated, these aberrations can be compensated for using deformable mirrors in a closed loop. Focal plane wavefront sensing enables the…

Tomography is an imaging technique that works by reconstructing a scene from acquired data in the form of line integrals of the imaging domain. A fundamental underlying assumption in the reconstruction procedure is the precise alignment of…

Numerical Analysis · Mathematics 2018-07-13 Toby Sanders

Ptychography is a scanning coherent diffractive imaging technique that enables imaging nanometer-scale features in extended samples. One main challenge is that widely used iterative image reconstruction methods often require significant…

Image and Video Processing · Electrical Eng. & Systems 2024-12-17 Canberk Ekmekci , Tekin Bicer , Zichao Wendy Di , Junjing Deng , Mujdat Cetin