A design method OF 2-D axial-symmetric paraunitary filter banks with a lattice structure

A lattice structure of 2-D axial-symmetric paraunitary filter banks (ASPUFBs) is proposed, which makes it possible to design such filter banks in a systematic manner. ASPUFBs consist of non-separable axial-symmetric (AS) filters, and can be regarded as a subclass of non-separable linear-phase paraunitary (PU) ones. The AS property is desirable for image processing, because it enables us to use the symmetric extension method. Since our proposed system structurally restricts both the PU and AS properties, it can be designed by using an unconstrained optimization process. A design example will be given to show the significance of the lattice structure.