Efficient 2-D and multi-D symmetric FIR filter structures

In literature, the symmetries are usually used to reduce the number of multiplications without affecting the number of additions. The author shows that the symmetries can be exploited not only to reduce the number of multiplications as much as usual but also to reduce significantly the number of additions. Moreover, the required number of delay units remains minimum. A number of 2-D FIR filter structures are proposed for linear-phase filters having: (1) centrosymmetry, (2) quadrisymmetry, (3) octosymmetry. The same methodology is also applicable to multi-D symmetric filters