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A new method for SAR speckle reduction
IEEE International Geoscience and Remote Sensing Symposium, 2003A new method derived from the Frost filter kernel for SAR (synthetic aperture radar) image speckle reduction is introduced. In the speckle reduction procedure, both the statistical information of the central pixel in the filter window and that of the neighborhood pixels are used.
Zhaohui Zhang +2 more
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Hadamard speckle contrast reduction
Optics Letters, 2004The condition for a diffuser to produce the maximum speckle contrast reduction with the minimum number of distinct phase patterns is derived. A binary realization of this optimum diffuser is obtained by mapping the rows or columns of a Hadamard matrix to the phase patterns.
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Speckle noise reduction in SAS imagery
Signal Processing, 2007Synthetic aperture sonar (SAS) is actively used in sea bed imagery. Indeed high resolution images provided by SAS are of great interest, especially for the detection, localization and eventually classification of objects lying on sea bed. SAS images are highly corrupted by a granular multiplicative noise, called speckle noise which reduces spatial and ...
Fabien Chaillan +2 more
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Speckle Reduction by Double Recorded Holograms
Applied Optics, 1973A method of speckle reduction in holography for 2-D objects with minimum recording area is presented. The image is incoherently synthesized from the hologram double recorded with a set of random phase plates.
M, Kato, Y, Okino
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Reduction of speckle noise in multiwavelength contouring
Applied Optics, 2012We report on a method that can be used to improve the result of multiwavelength contouring in the case of objects with rough surface. It is based on the combined evaluation of multiple measurements with varying direction of illumination. While the individual measurements share the same systematics with respect to the shape of the investigated object ...
Claas, Falldorf +3 more
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Speckle-modulation for speckle reduction in optical coherence tomography
Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XXII, 2018Optical coherence tomography (OCT) is a powerful biomedical imaging technology that relies on the coherent detection of backscattered light to image tissue morphology in vivo. As a consequence, OCT is susceptible to coherent noise, known as speckle noise, which imposes significant limitations on its diagnostic capabilities.
Adam de la Zerda +7 more
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Speckle Reduction in Images with WEAD and WECD
2006In this paper we discuss the speckle reduction in images with the recently proposed Wavelet Embedded Anisotropic Diffusion (WEAD) and Wavelet Embedded Complex Diffusion (WECD). Both these methods are improvements over anisotropic and complex diffusion by adding wavelet based bayes shrink in its second stage.
Jeny Rajan, M. R. Kaimal 0001
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Reduction of speckles in retinal reflection
Applied Physics Letters, 2007Speckle noise can deteriorate the quality of wave-front sensors measuring ocular aberrations. To counter that, a narrow laser beam was acoustically modulated before entering the eye and creating a spot on the retina. Light was scattered back through the aberrations into the sensor.
Vassilios Albanis +2 more
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1986
Abstract : The presence of speckle in imagery produced with coherent illumination (e.g., synthetic aperture radar) reduces the detectability of objects in the images. It also reduces the effectiveness of some computer algorithms (e.g., edge detection) designed for automatic image analysis.
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Abstract : The presence of speckle in imagery produced with coherent illumination (e.g., synthetic aperture radar) reduces the detectability of objects in the images. It also reduces the effectiveness of some computer algorithms (e.g., edge detection) designed for automatic image analysis.
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SPIE Proceedings, 1987
A new approach towards the recognition and removal of the speckle artefact in ultrasound pulse-echo images is presented. The technique utilises the behaviour of the signal's instantaneous frequency, which is the time derivative of the temporal phase. In contrast to all other approaches, the proposed method allows the speckle artefact to be recognised ...
S. Leeman, D. A. Seggie
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A new approach towards the recognition and removal of the speckle artefact in ultrasound pulse-echo images is presented. The technique utilises the behaviour of the signal's instantaneous frequency, which is the time derivative of the temporal phase. In contrast to all other approaches, the proposed method allows the speckle artefact to be recognised ...
S. Leeman, D. A. Seggie
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