[comp.dsp] 2-D FIR design question

crounse@norton.uucp (Great Rumpuscat) (04/09/91)

	I am working on a problem in image halftoning which requires
a 2-D FIR filter which has a near circular-symmetric frequency response.
That is, its 2-D DTFT should depend only on the radial frequency.  I am
fairly convinced that this cannot be done with a finite impulse 
response.  Does anyone know of any references concerning how close 
(by some measure) one can get?         

Thanks,
ken.
,,,,,,,,,,,,,,,,,crounse@norton.berkeley.edu,,,,,,,,,,,,,,,,,,,,,,,
Kenneth R. Crounse,      -  UC Berkeley
King of                  -  (Rally Behind the Ridiculous)
Randomness and           -  Dept. of EECS
Chaos                    -  Nonlinear Electronics Laboratory