Objects in the Wavelet Toolbox Software

Four classes of objects are defined in the Wavelet Toolbox™ software.

The hierarchical organization of these objects is described in the following scheme:

Only the Wavelet Packet functions (1-D and 2-D) use the previous objects. More precisely, WPTREE objects are used to build wavelet packets.

A short description of this hierarchy of objects follows.

The WTBO class is an abstract class. Any object in the toolbox is parented by a WTBO object and would inherit the methods and fields of the WTBO class.

The NTREE class is dedicated to tree manipulation (node labels, node splitting, node merging, ...), and it is also an abstract class. The main methods are

nodejoin, which recomposes nodes
nodesplt, which decomposes nodes
wtreemgr, which lets you access most of tree and node information (order, depth, terminal nodes, ascendants of a node, ...)

In fact, the wtreemgr method is not used directly, but you can use the functions treeord, treedpth, leaves, nodeasc, ..., and the method get.

The DTREE class is dedicated to trees with associated data: vectors or matrices.

This class is also an abstract class and some methods have to be overloaded.

The aim of the WPTREE class is to manage wavelet packets 1-D and 2-D.

Some methods of the DTREE class have been overloaded, for example: split, merge, and recons.

Most of the methods are specific to the class WPTREE; for example: bestlevt, besttree, and wp2wtree.

By typing help wavelet you can see the available methods in the Tree Management Utilities and Wavelet Packets sections.