An improved stability test algorithm for two-dimensional digital filters

In this paper, we show that the tabular algorithm given by Jury (1991) for obtaining inner determinants with numerical entries is also valid for the case of polynomial entries. Based on this algorithm, the new stability criterion recently proposed by Yang et al. (1998) for two-dimensional (2-D) digital filters can be efficiently implemented. As compared with the tabular algorithm given by Yang et al., the proposed algorithm leads to a great reduction in the order of polynomial entries of the array from n/sub 2/2/sup n1-1/ to n/sub 1/n/sub 2/.