On the circular symmetry of 2-D recursive filters obtained from 1 -D prototypes
G.M. Cortelazzo, Gian Antonio Mian · IEEE Transactions on Circuits and Systems II Analog and Digital Signal Processing · 1992
The circularity characteristics of the 2-D recursive filters derived from the cascade of rotations of 2-D sections obtained from analog or digital prototypes are examined and compared. A set of instructive design examples giving a simple and clear picture of the possibilities of the methods is presented.>