Results 191 to 200 of about 1,765,935 (236)
Some of the next articles are maybe not open access.
1975
Prior work dealing with optical imaging of sound waves was devoted to nondestructive testing applications at sound frequencies of 1 MHz and higher. Bragg diffraction of light by sound waves permits one to obtain optical images of sound fields on a real time basis.
J. H. Cole +3 more
openaire +1 more source
Prior work dealing with optical imaging of sound waves was devoted to nondestructive testing applications at sound frequencies of 1 MHz and higher. Bragg diffraction of light by sound waves permits one to obtain optical images of sound fields on a real time basis.
J. H. Cole +3 more
openaire +1 more source
Bayesian Hyperanalytic Denoising of SONAR Images
IEEE Geoscience and Remote Sensing Letters, 2011The SOund Navigation And Ranging (SONAR) images are perturbed by speckle noise. This paper presents a new denoising method in the wavelet domain, which tends to reduce the speckle, preserving the structural features and the textural information of the scene.
Ioana Firoiu +3 more
openaire +1 more source
Imaging sonar performance estimation
The Journal of the Acoustical Society of America, 2022Imaging sonar systems including forward looking sonars, synthetic aperture sonars, and real aperture sonars produce large quantities of data and are often connected to automated target recognition (ATR) algorithms. Performance of these algorithms degrades, sometimes significantly, with changes in environmental reverberation, seafloor sediment ...
Brian O'Donnell +2 more
openaire +1 more source
Unsupervised segmentation applied on sonar images
1997This work deals with unsupervised sonar image segmentation. We present a new estimation segmentation procedure using the recent iterative method of estimation called Iterative Conditional Estimation (ICE) [1]. This method takes into account the variety of the laws in the distribution mixture of a sonar image and the estimation of the parameters of the ...
Maurice Mignotte +3 more
openaire +2 more sources
2008
In this thesis, a sonar mine detection system is presented. The three stages of the system, image enhancement, edge detection and data compression are analyzed. For each stage, different approaches are studied and the appropriate algorithm is chosen. For image enhancement, a cascaded morphological enhancement algorithm is developed.
openaire +1 more source
In this thesis, a sonar mine detection system is presented. The three stages of the system, image enhancement, edge detection and data compression are analyzed. For each stage, different approaches are studied and the appropriate algorithm is chosen. For image enhancement, a cascaded morphological enhancement algorithm is developed.
openaire +1 more source
Segmentation of Multispectral Sonar Images
1995Acoustic images obtained from sonar may consist of multiple objects like undersea vehicles, ship wrecks, rocks, mines etc. Sometimes, strong echoes due to surface or bottom reverberation may also cause confusion in interpretation of such images. Such complex scenarios with multiple objects would first require segmentation of the acoustic image to ...
N. Rajpal, R. Bahl, E. P. Selvan
openaire +1 more source
Sonar image interpretation and modelling
Proceedings of Symposium on Autonomous Underwater Vehicle Technology, 2002The problem addressed is that of providing a model-based system to interpret sonar data from an autonomous or remotely controlled vehicle instrumentation, to aid navigation, improve sea floor mapping techniques, identify objects, simulate acoustic images for survey and analysis, or to aid the design of sonar systems.
G.T. Russell +3 more
openaire +1 more source
Underwater Localization and Mapping with Imaging Sonar
2019Acoustic imaging sonars have been used for a variety of tasks intended to increase the autonomous capabilities of underwater vehicles. Among the most critical tasks of any autonomous vehicle are localization and mapping, which are the focus of this work.
openaire +1 more source
Imaging sonar system and method
The Journal of the Acoustical Society of America, 1983An imaging sonar system is disclosed comprising a transmitter, a receiver, and a rotatable transducer coupled with the transmitter and receiver for generating sound waves and for detecting echoes therefrom. Drive means are provided for rotating the rotatable transducer.
William F. Stembridge +2 more
openaire +1 more source
Synthetic aperture sonar applied to a multibeam volume imaging sonar
The Journal of the Acoustical Society of America, 2004The possibility of using synthetic aperture sonar (SAS) processing techniques on a multibeam volume imaging sonar (the Buried Object Search Sonar, or BOSS) is explored. A system algorithm is developed which involves first forming several parallel synthetic apertures from a translated array oriented in the cross-track direction, then beamforming the ...
openaire +1 more source