A new WLS method for the design of two-dimensional FIR digital filters

Recently, the weighted least square (WLS) technique for the FIR filter design has received wide attention, since it is computationally more efficient than other minimax techniques. However, for two-dimensional (2-D) filter design, the conventional WLS technique rearranges the frequency samples and the impulse filter coefficients with 2-D form into 1-D form, thus the WLS technique results in expensive computation. This paper presents a new 2-D FIR filter design method which retains the frequency samples and impulse filter coefficients in their 2-D form. Experimental results show that the new technique is computationally very efficient and leads to nearly-optimal approximations.