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Soft shrinking

Purpose
Description
Example
Macro Synopsis
Modules
Related Functions
References


Purpose

Noise reduction by wavelet soft shrinking

Description

"Soft shrinking" removes noise from the input signal x by the following steps:
  1. compute the discrete wavelet transform of x
  2. replace each value d of each detail signal by

    where the threshold t is , r is the noise level, and N the length of x.

Parameters are



Example

"Soft shrinking" is used for the filtering of nonstationary time series, and the smoothing of signals with unknown type of noise.

Macro Synopsis

y = WaveletSoftShrink(x,n,r);
signal x,y;
int n;
float r;

Modules

Wavelet

Related Functions

Define wavelet, Load wavelet, Save wavelet, Decompose, Reconstruct, Hard shrinking, Sure shrinking.

References

Donoho [35]