Thresholding estimators for minimax restoration and deconvolution
نویسندگان
چکیده
Inverting the distortion of signals and images in presence of additive noise is often numerically unstable. To solve these ill-posed inverse problems, we study linear and non-linear diagonal estimators in an orthogonal basis. General conditions are given to build nearly minimax optimal estimators with a thresholding in an orthogonal basis. As an application, we study the deconvolution of bounded variation signals, with numerical results on the deblurring of satellite images.
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