Design of 2D filter banks based on 1D lattice structure

This paper proposes a design procedure for the 2D linear-phase para-unitary filter bank, based on the 1D lattice structure. As the first step, the perfect reconstruction conditions of 1D and 2D cases are compared, and it is shown that the 2D filter bank satisfying the perfect reconstruction condition can be realized by the 1D lattice structure with a constraint. It is known, on the other hand, that the 1D perfect reconstruction filter bank can be converted to the lattice structure, using only half of the filter coefficients, and a simple optimization procedure can derive the whole filter coefficients. Based on those investigations, it is shown that the 2D filter bank can be designed by directly designing only half of the channels of the 2D filter bank in the time domain.