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Related papers: Bessel Speckles

200 papers

We put forward a technique to unveil to which symmetry group a nonlinear crystal belongs, making use of nonlinear optics with structured light. We consider as example the process of spontaneous parametric down-conversion. The crystal, which…

Optics · Physics 2015-07-01 Rocio Jauregui , Juan P. Torres

We propose a novel approach for pixel classification in hyperspectral images, leveraging on both the spatial and spectral information in the data. The introduced method relies on a recently proposed framework for learning on distributions…

Computer Vision and Pattern Recognition · Computer Science 2016-05-31 Gianni Franchi , Jesus Angulo , Dino Sejdinovic

Ion Beam Sputtering (IBS) is a cost-effective technique able to produce ordered nanopatterns on the surfaces of different materials. To date, most theoretical studies of this process have focused on systems which become amorphous under…

Mesoscale and Nanoscale Physics · Physics 2016-05-04 Javier Renedo , Javier Muñoz-García , Mario Castro , Rodolfo Cuerno

In this paper we analyze an imaging technique based on intensity speckle correlations over incident field position proposed in [J. A. Newmann and K. J. Webb, Phys. Rev. Lett. 113, 263903 (2014)]. Its purpose is to reconstruct a field…

Analysis of PDEs · Mathematics 2018-08-01 Josselin Garnier , Knut Solna

Superpixels are widely used in computer vision to simplify image representation and reduce computational complexity. While traditional methods rely on low-level features, deep learning-based approaches leverage high-level features but also…

Computer Vision and Pattern Recognition · Computer Science 2025-09-17 Julien Walther , Rémi Giraud , Michaël Clément

Spectral imaging has recently gained traction for face recognition in biometric systems. We investigate the merits of spectral imaging for face recognition and the current challenges that hamper the widespread deployment of spectral sensors…

Computer Vision and Pattern Recognition · Computer Science 2020-01-06 Rumaisah Munir , Rizwan Ahmed Khan

Nowadays, hyperspectral image classification widely copes with spatial information to improve accuracy. One of the most popular way to integrate such information is to extract hierarchical features from a multiscale segmentation. In the…

Computer Vision and Pattern Recognition · Computer Science 2016-06-17 Yanwei Cui , Laetitia Chapel , Sébastien Lefèvre

Current theories of perception suggest that the brain represents features of the world as probability distributions, but can such uncertain foundations provide the basis for everyday vision? Perceiving objects and scenes requires knowing…

Neurons and Cognition · Quantitative Biology 2022-11-30 Andrey Chetverikov , Árni Kristjánsson

Clustering of hyperspectral images is a fundamental but challenging task. The recent development of hyperspectral image clustering has evolved from shallow models to deep and achieved promising results in many benchmark datasets. However,…

Computer Vision and Pattern Recognition · Computer Science 2021-11-16 Yaoming Cai , Zijia Zhang , Yan Liu , Pedram Ghamisi , Kun Li , Xiaobo Liu , Zhihua Cai

A novel, non-learning-based, saliency-aware, shape-cognizant correspondence determination technique is proposed for matching image pairs that are significantly disparate in nature. Images in the real world often exhibit high degrees of…

Computer Vision and Pattern Recognition · Computer Science 2018-09-14 Arun CS Kumar , Shefali Srivastava , Anirban Mukhopadhyay , Suchendra M. Bhandarkar

As lensing of coherent astrophysical sources e.g. pulsars, fast radio bursts, and gravitational waves becomes observationally relevant, the mathematical framework of Picard-Lefschetz theory has recently been introduced to fully account for…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-02 Xun Shi

Speckle patterns produced by coherent X-ray have a close relationship with the internal structure of materials but quantitative inversion of the relationship to determine structure from speckle patterns is challenging. Here, we investigate…

The propagation of monochromatic light through a scattering medium produces speckle patterns in reflection and transmission, and the apparent randomness of these patterns prevents direct imaging through thick turbid media. Yet, since…

Recently, novel imaging techniques based on the 'memory-effect' speckle-correlations have enabled diffraction-limited imaging through scattering layers and around corners. These techniques, however, are currently limited to imaging only…

Optics · Physics 2018-11-14 Ofer Salhov , Gil Weinberg , Ori Katz

We study the intensity spatial correlation function of optical speckle patterns above a disordered dielectric medium in the multiple scattering regime. The intensity distributions are recorded by scanning near-field optical microscopy…

The propagation of a Bessel beam (or Bessel-X wave) is analyzed on the basis of a vectorial treatment. The electric and magnetic fields are obtained by considering a realistic situation able to generate that kind of scalar field.…

Optics · Physics 2009-11-11 D. Mugnai , I. Mochi

Speckle-correlation imaging techniques are widely used for non-invasive imaging through complex scattering media. While light propagation through multimode fibers and scattering media share many analogies, reconstructing images through…

Scalar Bessel beams are derived both via the wave equation and via diffraction theory. While such beams have a group velocity that exceeds the speed of light, this is a manifestation of the "scissors paradox" of special relativty. The…

Optics · Physics 2007-05-23 Kirk T. McDonald

The phenomenon of sequential vibrational resonance existed in a multistable system that is excited by both high- and low-frequency signals is reported. By the method of direct separation of motions, the theoretical investigation on…

Chaotic Dynamics · Physics 2011-06-20 J. H. Yang , X. B. Liu

Bursts of images exhibit significant self-similarity across both time and space. This motivates a representation of the kernels as linear combinations of a small set of basis elements. To this end, we introduce a novel basis prediction…

Computer Vision and Pattern Recognition · Computer Science 2020-12-04 Zhihao Xia , Federico Perazzi , Michaël Gharbi , Kalyan Sunkavalli , Ayan Chakrabarti