Deconvolution by thresholding in mirror wavelet bases
نویسندگان
چکیده
The deconvolution of signals is studied with thresholding estimators that decompose signals in an orthonormal basis and threshold the resulting coefficients. A general criterion is established to choose the orthonormal basis in order to minimize the estimation risk. Wavelet bases are highly sub-optimal to restore signals and images blurred by a low-pass filter whose transfer function vanishes at high frequencies. A new orthonormal basis called mirror wavelet basis is constructed to minimize the risk for such deconvolutions. An application to the restoration of satellite images is shown.
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عنوان ژورنال:
- IEEE transactions on image processing : a publication of the IEEE Signal Processing Society
دوره 12 4 شماره
صفحات -
تاریخ انتشار 2003