Characterization of Piecewise Smooth Images with Wavelets: Application to Noise Variance Estimation

نویسنده

  • Sylvain Meignen
چکیده

We propose a novel approach to the characterization of geometric regions by use of wavelet coefficients. We show that in the absence of noise, geometric regions with edges behave differently from other regions as far as the evolution of their wavelet coefficients through scales is concerned. We use this particularity to identify piecewise smooth subimages in a noisy context on which we perform noise variance estimation, for white noise and 1/f noise.

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تاریخ انتشار 2005