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Photoacoustic microscopy (PAM) is a novel implementation of photoacoustic imaging (PAI) for visualizing the 3D bio-structure, which is realized by raster scanning of the tissue. However, as three involved critical imaging parameters,…

Image and Video Processing · Electrical Eng. & Systems 2023-08-10 Zhengyuan Zhang , Haoran Jin , Zesheng Zheng , Wenwen Zhang , Wenhao Lu , Feng Qin , Arunima Sharma , Manojit Pramanik , Yuanjin Zheng

Maps of the magnetic field at the Sun's surface are commonly used as boundary conditions in space-weather modeling. However, continuous observations are only available from the Sun's Earth-facing side. One commonly used approach to mitigate…

Solar and Stellar Astrophysics · Physics 2024-12-02 Dan Yang , Stephan G. Heinemann , Robert H. Cameron , Laurent Gizon

Image defogging is a technique used extensively for enhancing visual quality of images in bad weather condition. Even though defogging algorithms have been well studied, defogging performance is degraded by demosaicking artifacts and sensor…

Computer Vision and Pattern Recognition · Computer Science 2017-05-24 Y. J. Lee , K. Hirakawa , T. Q. Nguyen

Optoacoustic image formation is conventionally based upon ultrasound time-of-flight readings from multiple detection positions. Herein, we exploit acoustic scattering to physically encode the position of optical absorbers in the acquired…

Biological Physics · Physics 2019-10-30 Xose Luis Dean-Ben , Ali Ozbek , Hernan Lopez-Schier , Daniel Razansky

A novel approach to improving the performances of confocal scanning imaging is proposed. We experimentally demonstrate its feasibility using acoustic waves. It relies on a new way to encode spatial information using the temporal dimension.…

Results of forward modelling of acoustic wave propagation in a realistic solar sub-photosphere with two cases of steady horizontal flows are presented and analysed by the means of local helioseismology. The simulations are based on fully…

Astrophysics · Physics 2009-11-13 S. Shelyag , R. Erdelyi , M. J. Thompson

Surface topography refers to the geometric micro-structure of a surface and defines its tactile characteristics (typically in the sub-millimeter range). High-resolution 3D scanning techniques developed recently enable the 3D reconstruction…

Computer Vision and Pattern Recognition · Computer Science 2015-05-07 Matthias Zeppelzauer , Markus Seidl

Scanning acoustic microscopy (SAM) has been employed since microscopic images are widely used for biomedical or materials research. Acoustic imaging is an important and well-established method used in nondestructive testing (NDT),…

Image and Video Processing · Electrical Eng. & Systems 2022-08-09 Shubham Kumar Gupta , Azeem Ahmad , Prakhar Kumar , Frank Melandso , Anowarul Habib

Recent observations of helioseismic holography revealed that magnetic fields inclined to the line-of-sight direction could cause systematic variations in measured acoustic phase shifts, and that the surface magnetic field may shift the…

Astrophysics · Physics 2009-11-11 Junwei Zhao , Alexander G. Kosovichev

Correct interpretation of acoustic travel times measured by time-distance helioseismology is essential to get an accurate understanding of the solar properties that are inferred from them. It has long been observed that sunspots suppress…

Solar and Stellar Astrophysics · Physics 2015-05-14 R. Nigam , A. G. Kosovichev

Photoacoustic microscopy (PAM) is an emerging imaging method combining light and sound. However, limited by the laser's repetition rate, state-of-the-art high-speed PAM technology often sacrifices spatial sampling density (i.e.,…

Image and Video Processing · Electrical Eng. & Systems 2021-04-09 Tri Vu , Anthony DiSpirito , Daiwei Li , Zixuan Zhang , Xiaoyi Zhu , Maomao Chen , Laiming Jiang , Dong Zhang , Jianwen Luo , Yu Shrike Zhang , Qifa Zhou , Roarke Horstmeyer , Junjie Yao

It is critical to characterize the carrier and instantaneous frequency distribution variation in ultrafast processes, all of which are determined by the optical phase. Nevertheless, there is no method that can single-shot record the…

Optics · Physics 2021-06-18 Wenchao Wang , Tianhao Xian , Li Zhan

Remote sensing image fusion is an effective way to use a large volume of data from multisensor images. Most earth satellites such as SPOT, Landsat 7, IKONOS and QuickBird provide both panchromatic (Pan) images at a higher spatial resolution…

Computer Vision and Pattern Recognition · Computer Science 2014-03-24 Reham Gharbia , Ahmad Taher Azar , Ali El Baz , Aboul Ella Hassanien

Time-distance helioseismology and related techniques show great promise for probing the structure and dynamics of the subphotospheric layers of the Sun. Indeed time-distance helioseismology has already been applied to make inferences about…

Solar and Stellar Astrophysics · Physics 2010-02-12 L. Gizon , M. J. Thompson

Helioseismic holography is a powerful technique used to probe the solar interior based on estimations of the 3D wavefield. Porter--Bojarski holography, which is a well-established method used in acoustics to recover sources and scatterers…

Solar and Stellar Astrophysics · Physics 2018-02-14 Dan Yang

We present a new method for helioseismic diagnostics of the three-dimensional structure of sound speed, magnetic fields and flow velocities in the convection zone by inversion of acoustic travel-time data. The data are measurements of the…

Solar and Stellar Astrophysics · Physics 2018-06-11 A. G. Kosovichev , T. L. Duvall

Hyperspectral imaging has been increasingly used for underwater survey applications over the past years. As many hyperspectral cameras work as push-broom scanners, their use is usually limited to the creation of photo-mosaics based on a…

Computer Vision and Pattern Recognition · Computer Science 2021-10-14 Maxime Ferrera , Aurélien Arnaubec , Klemen Istenic , Nuno Gracias , Touria Bajjouk

Digital holographic microcopy is a thriving imaging modality that attracts considerable research interest due to its ability to not only create excellent label-free contrast, but also supply valuable physical information regarding the…

Optics · Physics 2019-04-01 Gili Dardikman , Natan T. Shaked

A crucial limitation of current high-resolution 3D photoacoustic tomography (PAT) devices that employ sequential scanning is their long acquisition time. In previous work, we demonstrated how to use compressed sensing techniques to improve…

Numerical Analysis · Mathematics 2020-09-07 Felix Lucka , Nam Huynh , Marta Betcke , Edward Zhang , Paul Beard , Ben Cox , Simon Arridge

Spectral imaging enables spatially-resolved identification of materials in remote sensing, biomedicine, and astronomy. However, acquisition times require balancing spectral and spatial resolution with signal-to-noise. Hyperspectral imaging…

Computer Vision and Pattern Recognition · Computer Science 2020-03-17 Nguyen Tran , Rupali Mankar , David Mayerich , Zhu Han