Modified stability table for 2-D digital filters

A modified stability table is obtained for checking the stability of 2-D digital filters. In this table, the appropriate entries of the first column are equivalent to the appropriate minors of the Hermitian Schur-Cohn matrix. Thus the positivity of the latter matrix requires the positivity checking of the (n-1) appropriate entries for one point, and the last entry, which is equivalent to the Schur-Cohn determinant, is to be checked for positivity for all |z|=1. This test is simpler than several others appearing in the literature