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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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The Use of ICA in Speckle Noise
2004When a linear mixture of independent sources is contaminated by multiplicative noise, also called speckle noise, the statistic of the outputs of a linear transformation of the noise data is very different from the statistic that appears when the speckle noise is not present.
David Blanco +4 more
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Introducing speckle noise maps for Laser Vibrometry [PDF]
Optics and Lasers in Engineering, 2009 When coherent light scatters from a surface, which is rough on the scale of the wavelength of the light, a speckle pattern is produced. The Laser Vibrometer measures target vibration velocity in the direction of the incident laser beam and typically ...
Steve Rothberg
exaly +3 more sources
Radar speckle: noise or information?
IGARSS '96. 1996 International Geoscience and Remote Sensing Symposium, 2002The authors examine radar speckle from a non-traditional perspective. Instead of viewing radar speckle as noise, they attempt to assess the information content of radar speckle. A speckle identification algorithm is developed to separate speckle from pixels of "normal" returns. The relationships between land cover types and the density and roughness of
null Zong-Guo Xia, null Yongwei Sheng
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Techniques For Speckle Noise Removal
Optical Engineering, 1981In this paper, several techniques to reduce speckle noise (more generally signal independent multiplicative noise) in images are studied. The techniques include gray scale modification, frame averaging, low-pass filtering in the intensity and density domains, and application of the short space spectral subtraction image restoration technique in the ...
Jae S. Lim, Hamid Nawab
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Speckle revisited: analysis of speckle noise in bar-code scanning systems
SPIE Proceedings, 2001-
Marom, E. +2 more
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Applied Optics, 1987
Heterodyne techniques greatly improved the accuracy in readout systems for holographic interferometry and dual plate speckle photogrammetry, since the order of interference fringes is read via phase measurements. The limiting accuracy has been traditionally associated with scintillation noise.
J S, Kim +3 more
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Heterodyne techniques greatly improved the accuracy in readout systems for holographic interferometry and dual plate speckle photogrammetry, since the order of interference fringes is read via phase measurements. The limiting accuracy has been traditionally associated with scintillation noise.
J S, Kim +3 more
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Speckle noise removal by robust modeling
Proceedings 2003 International Conference on Image Processing (Cat. No.03CH37429), 2004A robust modeling approach is applied to remove speckle noise in synthetic aperture images. Conventional adaptive filtering approaches in speckle filtering smoothes the image selectively depending on the details of underlying textures, and tend to blur details after speckle removal.
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Non-Gaussian statistics of speckle noise of Young's fringes in speckle velocimetry
Applied Optics, 1985In speckle velocimetry, Young's fringes observed during analysis of the multiple-exposure photographs of tracer particles seeding a fluid flow are embedded in a speckle noise that renders their analysis difficult. Some first- and second-order statistical properties of this speckle background are considered in this paper.
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Unsupervised estimation of speckle noise in radar images
International Journal of Imaging Systems and Technology, 1992AbstractSpeckle in radar images has the characteristic of a multiplicative noise. In this article, two unsupervised methods are introduced to estimate the speckle noise statistics using the mean and the standard deviation of small image blocks (4 × 4, or 6 × 6 pixels).
Jong-Sen Lee +2 more
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