waverec (Wavelet Toolbox)

Multilevel 1-D wavelet reconstruction

Syntax

X = waverec(C,L,'wname')
X = waverec(C,L,Lo_R,Hi_R)

Description

waverec performs a multilevel one-dimensional wavelet reconstruction using either a specific wavelet ('wname', see wfilters) or specific reconstruction filters (Lo_R and Hi_R). waverec is the inverse function of wavedec in the sense that the abstract statement waverec(wavedec(X,N,'wname'),'wname') returns X.

X = waverec(C,L,'wname') reconstructs the signal X based on the multilevel wavelet decomposition structure [C,L] and wavelet 'wname'. (For information about the decomposition structure, see wavedec.)

X = waverec(C,L,Lo_R,Hi_R) reconstructs the signal X as above, using the reconstruction filters you specify. Lo_R is the reconstruction low-pass filter and Hi_R is the reconstruction high-pass filter.

Note that X = waverec(C,L,'wname') is equivalent to X = appcoef(C,L,'wname',0).

Examples

% The current extension mode is zero-padding (see dwtmode).

% Load original one-dimensional signal. 
load leleccum; s = leleccum(1:3920); ls = length(s); 

% Perform decomposition of signal at level 3 using db5. 
[c,l] = wavedec(s,3,'db5');

% Reconstruct s from the wavelet decomposition structure [c,l]. 
a0 = waverec(c,l,'db5');

% Check for perfect reconstruction. 
err = norm(s-a0)
err =
    3.2079e-09

See Also
appcoef, idwt, wavedec

wavenames waverec2