Title :
Robust wavelet denoising
Author :
Sardy, Sylvain ; Tseng, Paul ; Bruce, Andrew
Author_Institution :
Dept. of Math., Swiss Federal Inst. of Technol., Lausanne, Switzerland
fDate :
6/1/2001 12:00:00 AM
Abstract :
For extracting a signal from noisy data, waveshrink and basis pursuit are powerful tools both from an empirical and asymptotic point of view. They are especially efficient at estimating spatially inhomogeneous signals when the noise is Gaussian. Their performance is altered when the noise has a long tail distribution, for instance, when outliers are present. We propose a robust wavelet-based estimator using a robust loss function. This entails solving a nontrivial optimization problem and appropriately choosing the smoothing and robustness parameters. We illustrate the advantage of the robust wavelet denoising procedure on simulated and real data
Keywords :
Gaussian noise; optimisation; parameter estimation; signal sampling; smoothing methods; wavelet transforms; Gaussian noise; basis pursuit; long tail distribution noise; noisy data; nontrivial optimization problem; outliers; performance; real data; robust loss function; robust wavelet denoising; robust wavelet-based estimator; robustness parameters; signal extraction; signal sampling; simulated data; smoothing parameters; spatially inhomogeneous signal estimation; waveshrink; Closed-form solution; Covariance matrix; Data mining; Gaussian noise; Least squares approximation; Mathematics; Noise reduction; Noise robustness; Smoothing methods; Wavelet coefficients;
Journal_Title :
Signal Processing, IEEE Transactions on