function y = idct_2(x) % % Homebrew 2-D IDCT Program Based on ifft2 % [n1 n2]=size(x); % % Make 2n1 x 2n2 function % intermediate=zeros(2*n1,2*n2); % % Define Basic Twiddle Grid % twiddle=??; % % Zone 1 % intermediate(??)=??; % % Zone2 % intermediate(??)=??; % % Zone3 % intermediate(??)=??; % % Zone4 % intermediate(??)=??; % % Special Cases % intermediate(??)=0; % % Take 2n1 x 2n2 ifft2 % intermediate=ifft2(intermediate); % % Compute n1 x n2 image % y=??; y=real(y); % % Finish the Function %