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Resumen de Publicaciones |
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Wavelet |
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Otros |
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1989 |
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A theory for multiresolution signal decomposition: the wavelet representation |
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S. Mallat |
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IEEE Transactions on Pattern Analysis and Machine Intelligence Vol 11, Nr0. 7, |
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198Jul. 1989, pp. 6p.674-693 |
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Abstract : |
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Multiresolution representations are effective for analyzing the information content of |
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images. The properties of the operator which approximates a signal at a given resolution |
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were studied. It is shown that the difference of information between the approximation of |
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a signal at the resolutions 2/sup j+1/ and 2/sup j/ (where j is an integer) can be extracted |
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by decomposing this signal on a wavelet orthonormal basis of L/sup 2/(R/sup n/), the |
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vector space of measurable, square-integrable n-dimensional functions. In L/sup 2/(R), a |
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wavelet orthonormal basis is a family of functions which is built by dilating and translating |
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a unique function psi (x). This decomposition defines an orthogonal multiresolution |
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representation called a wavelet representation. It is computed with a pyramidal algorithm |
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based on convolutions with quadrature mirror filters. Wavelet representation lies between |
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the spatial and Fourier domains. For images, the wavelet representation differentiates |
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several spatial orientations. The application of this representation to data compression in |
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image coding, texture discrimination and fractal analysis is discussed |
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1996 |
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A fuzzy-logic-based threshold function for signal recovery using discrete wavelet |
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transform |
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Wenbo Mei; Lik-Kwan Shark |
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Signal Processing, 1996., 3rd International Conference on , Volume: 1 , 1996 |
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Page(s): 283 -286 vol.1 |
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Abstract : |
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In this paper, a novel threshold function based on fuzzy logic is proposed to achieve good |
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signal recovery performance in the presence of noise using the discrete wavelet |
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transform. The proposed threshold is shown to provide an alternative and flexible |
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approach to solve the problems associated with the conventional hard-threshold approach. |
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Some typical results, obtained from the computer simulations of recovering a transient |
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signal embedded in additive white Gaussian noise in different signal-to-noise ratio settings, |
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are presented to demonstrate the potential and the effectiveness of the proposed |
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threshold function. |
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1999 |