Symmetric properties of 2-D sequences and their applications for designing quadrantally symmetric linear-phase 2-D FIR digital filters

In this paper, various symmetric and antisymmetric 2-D sequences are used to design quadrantally symmetric/antisymmetric 2-D filters. It is shown that there are sixteen types cases to be considered according to the symmetry/antisymmetry of 2-D sequences in both directions and their filter lengths (even or odd).