Multiresolution Markov Random Field Wavelet Shrinkage for Ripple Suppression in Sonar Imagery
نویسندگان
چکیده
A recent dual-tree wavelet shrinkage method to suppress sand ripples in sonar imagery is extended with a Markov random field framework. Markov chain Monte Carlo sampling is used to estimate the posterior marginal ripple state in the wavelet domain. Ripple suppression is realised by multiplying the dual-tree wavelet coefficients by the conditional probabilities of the non-ripple state. Tests on real data confirm that this extended method significantly further reduces false positives.
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