IUWFBT - Inverse Undecimated Wavelet Filterbank Tree

Usage

f = iuwfbt(c,info)
f = iuwfbt(c,wt)

Input parameters

Output parameters

Description

f = iuwfbt(c,info) reconstructs signal f from the coefficients c using parameters from info struct. both returned by the uwfbt function.

f = iuwfbt(c,wt) reconstructs signal f from the wavelet coefficients c using the undecimated wavelet filterbank tree described by wt.

Please see help for wfbt description of possible formats of wt.

Filter scaling:

As in uwfbt, the function recognizes three flags controlling scaling of the filters:

'sqrt'

Each filter is scaled by 1/sqrt(a), there a is the hop factor associated with it. If the original filterbank is orthonormal, the overall undecimated transform is a tight frame. This is the default.

'noscale'

Uses filters without scaling.

'scale'

Each filter is scaled by 1/a.

If 'noscale' is used, 'scale' must have been used in uwfbt (and vice versa) in order to obtain a perfect reconstruction.

Examples:

A simple example showing perfect reconstruction using the "full decomposition" wavelet tree:

f = greasy;
J = 6;
c = uwfbt(f,{'db8',J,'full'});
fhat = iuwfbt(c,{'db8',J,'full'});
% The following should give (almost) zero
norm(f-fhat)