The fully recursive filter: A general 2-D recursive filter
J. Woods, Ju-Hong Lee · IEEE Transactions on Acoustics Speech and Signal Processing · 1983
The conventional 2-D recursive filter can be thought of as performing a linear combination of 1-D filterings on past and present input and output data rows. All of these component 1-D filters are FIR except for that of the current output row. In a fully recursive filter all the component 1-D filters are IIR.