Journal ArticleDOI
A New Hybrid Method for Image Approximation Using the Easy Path Wavelet Transform
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A new hybrid method for image approximation is proposed that exploits the advantages of the usual tensor product wavelet transform for the representation of smooth images and uses the EPWT for an efficient representation of edges and texture.Abstract:
The easy path wavelet transform (EPWT) has recently been proposed by one of the authors as a tool for sparse representations of bivariate functions from discrete data, in particular from image data. The EPWT is a locally adaptive wavelet transform. It works along pathways through the array of function values and exploits the local correlations of the given data in a simple appropriate manner. However, the EPWT suffers from its adaptivity costs that arise from the storage of path vectors. In this paper, we propose a new hybrid method for image approximation that exploits the advantages of the usual tensor product wavelet transform for the representation of smooth images and uses the EPWT for an efficient representation of edges and texture. Numerical results show the efficiency of this procedure.read more
Citations
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Convergence Rates for Greedy Algorithms in Reduced Basis Methods
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A projection method to solve linear systems in tensor format
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On manifolds of tensors of fixed TT-rank
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On the low-rank approximation by the pivoted Cholesky decomposition
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References
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Journal ArticleDOI
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