Design of 3-D separable-denominator digital filters using minimal decomposition and balanced realization

Based on a concept of minimal decomposition and balanced model reduction, a novel technique is developed for designing 3-D separable-denominator digital filters in the spatial domain. The minimal decomposition reported here can be viewed as an extension of the reduced-dimensional decomposition for 2-D separable-denominator digital filters. The amount of calculation required here is relatively small. Moreover, the stability of the resulting filter is always guaranteed