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Title:
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Wavelet-domain Approximation and Compression of Piecewise Smooth Images |
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Author:
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Wakin, Michael; Romberg, Justin; Choi, Hyeokho; Baraniuk, Richard G.
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Type:
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Journal Paper |
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Keywords:
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Image compression; nonlinear approximation; wavelets; wedgelets; edges; wedgeprints |
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Citation:
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M. Wakin, J. Romberg, H. Choi and R. G. Baraniuk, "Wavelet-domain Approximation and Compression of Piecewise Smooth Images," IEEE Transactions on Image Processing, 2005. |
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Abstract:
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The wavelet transform provides a sparse representation for smooth images, enabling efficient approximation and compression using techniques such as zerotrees. Unfortunately, this sparsity does not extend to piecewise smooth images, where edge discontinuities separating smooth regions persist along smooth contours. This lack of sparsity hampers the efficiency of wavelet-based approximation and compression. On the class of images containing smooth C² regions separated by edges along smooth C² contours, for example, the asymptotic rate-distortion (R-D) performance of zerotree-based wavelet coding is limited to D(R) ~ 1/R, well below the optimal rate of 1/R².
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Date Published:
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2005-01-15 |
