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Analysis of strawberry ripening by dynamic speckle measurements
(SPIE, 2013-11)
This work seeks to determine the age of a fruit from observation of its dynamic speckle pattern. A mobile speckle pattern originates on the fruit's surface due to the interference of the wavefronts reflected from moving ...
Filtragem não-local do ruído Speckle em imagens SAR com modelagem estatística dos coeficientes da Wavelet de Haar e distâncias estocásticas
(Universidade Federal de São CarlosUFSCarPrograma de Pós-Graduação em Ciência da Computação - PPGCCCâmpus São Carlos, 2018-06-04)
Due to the coherent processing of synthetic aperture radar (SAR) systems, multiplicative
speckle noise arises providing a granular appearance in SAR images. This kind of noise
makes it difficult to analyse and interpret ...
Evaluation of the piezoelectric behaviour produced by a thick-film transducer using digital speckle pattern interferometry
(Elsevier, 2011-02)
This paper presents an interferometric measurement of the out-of-plane deflections produced by a piezoelectric transducer, manufactured by thick-film deposition of a ceramic paste over an alumina substrate, when is subjected ...
Experimental evaluation of a 3D wavelet-based phase recovery method in temporal speckle pattern interferometry
(Optical Society of America, 2017-05)
We test the performance of a phase recovery method based on a three-dimensional directional wavelet transform applied to the intensity signal measured by temporal speckle pattern interferometry (TSPI). We present and discuss ...
Probability mapping images in dynamic speckle classification
(Optical Society of America, 2013-02)
We propose the use of a learning procedure to identify regions of similar dynamics in speckle image sequences that includes more than one descriptor. This procedure is based on the application of a naïve Bayes statistical ...
Vortex analysis in dynamic speckle images
(Optical Society of America, 2009-12)
Optical vortex analysis has become an important tool in optical metrology. It has been shown to be able to measure small displacements with up to nanometric precision. We analyze optical vortex behavior in dynamic speckle ...
Effects of the induced birefringence in photorefractive crystals on speckle optical vortices
(Elsevier, 2012-03)
In this work, we show that it is possible to change the properties of an optical vortex formed in a speckle pattern by the control of an external electric field applied to a sillenite-type photorefractive material in a ...
A descriptor of speckle textures using box fractal dimension curve
(Elsevier, 2018-02)
We propose a simple generalization of the box fractal dimension in images by considering the curve obtained from its value as a function of the binarization threshold. This curve can be used to partially describe ordinary ...
Characterization of bio-dynamic speckles through classical and fuzzy mathematical morphology tools
(Elsevier Science, 2013-07)
In this paper we characterize dynamic speckle signals, obtaining selective information through the differentiation of morphological patterns of the temporal history of each pixel, using the morphological granulometric ...
Activity speckle images obtained from box fractal formalism
(Elsevier, 2019-10)
We propose a generalized Box Fractal algorithm to segment activity speckle images. The time history of the intensity value at every pixel of the frames is taken as a time series. The plot of this time series is then ...