Wavelet Toolbox

wthresh

Perform soft or hard thresholding

Syntax

• Y = wthresh(X,SORH,T)
  

Description

Y = wthresh(X,SORH,T) returns the soft (if SORH = 's') or hard (if SORH = 'h') T-thresholding of the input vector or matrix X. T is the threshold value.

Y = wthresh(X,'s',T) returns

, soft thresholding is wavelet shrinkage ( (x)₊ = 0 if x < 0; (x)₊ = x, if x 0 ).

Y = wthresh(X,'h',T) returns , hard thresholding is cruder.

Examples

• % Generate signal and set threshold. 
  y = linspace(-1,1,100); 
  thr = 0.4;
  
  % Perform hard thresholding. 
  ythard = wthresh(y,'h',thr);
  
  % Perform soft thresholding. 
  ytsoft = wthresh(y,'s',thr);
  
  % Using some plotting commands,
  % the following figure is generated.
  
  
  

See Also
wden, wdencmp, wpdencmp

wthcoef2

wthrmngr