Design of semicausal two-dimensional recursive filters

A procedure for the design of 2D recursive filters is developed using the Semicausal or half-plane filters. For recursive filters, semicausal or half-plane filters are more general than causal or quarter-plane filters to approximate the arbitrary magnitude characteristics. In approximating the given characteristics, the concept of 2D spectral factorization is utilized. A stabilization procedure is also presented and incorporated to produce the finite order stable filters. The transfer function of the resulting filter consists of both numerator and denominator polynomials.