Design of separable‐denominator two‐dimensional digital filters based on the reduced‐dimensional decomposition of frequency domain specifications

This paper proposes a new technique for design of separable‐denominator two‐dimensional digital filters (2DDF·s) in the frequency domain. The technique is based on decomposing both the transfer function of a separable‐denominator 2DDF and the given 2DDF frequency domain specification into a product of two one‐dimensional ones. By these decompositions, the design problem of a separable‐denominator 2DDF can be reduced to the design of two IDDF·s. The technique makes it possible to design separable‐denominator 2DDF·s by utilizing IDDF design techniques directly. Thus stable separable‐denominatro 2DD·s satisfying the given specifications can be designed efficiently.