DTWFBINIT Dual-Tree Wavelet Filterbank Initialization
Usage: dualwt=dtwfbinit(dualwtdef);
Input parameters:
dualwtdef : Dual-tree filterbank definition.
Output parameters:
dualwt : Dual-tree filtarbank structure.
dtwfinit() (a call without aguments) creates an empty structure. It
has the same fields as the struct. returned from WFBTINIT plus a field
to hold nodes from the second tree:
.nodes Filterbank nodes of the first tree
.dualnodes Filterbank nodes of the second tree
.children Indexes of children nodes
.parents Indexes of a parent node
.forder Frequency ordering of the resultant frequency bands.
dtwfinit({dualw,J,flag}) creates a structure representing a dual-tree
wavelet filterbank of depth J, using dual-tree wavelet filters
specified by dualw. The shape of the tree is controlled by flag.
Please see help on DTWFB or DTWFBREAL for description of the
parameters.
[dualwt,info]=dtwfinit(...) additionally returns info struct which
provides some information about the computed window:
info.tight
True if the overall tree construct a tight frame.
info.dw
A structure containing basic dual-tree filters as returned from
fwtinit(dualwtdef,'wfiltdt_').
Additional optional flags
-------------------------
'freq','nat'
Frequency or natural ordering of the resulting coefficient subbands.
Default ordering is 'freq'.
Package: ltfat