function [filtered_image] = lowpassFilter(img) N = 20; n=1; d=50; [x ~]=meshgrid(-floor(N/2):floor(N/2)-1,-floor(N/2):floor(N/2)-1); % Define B B = sqrt(2) - 1; % Define distance to centre D = sqrt(x.^2 + y.^2); f = 1 ./ (1 + B * ((d ./ D).^(2 * n))); filtered_image = conv2(img,f,'same'); end