dcttest.m

由上述实验过程的图像变化可知

   I = imread('lena1.bmp');
   data=zeros(8,8);
   for i=1:32
       for j=1:32
           col=(i-1)*8;
           row=(j-1)*8;
           for m=1:8
               for n=1:8
                  data(n,m)=I(row+n,col+m);
     %   I = rgb2gray(RGB);
     %   J = dct2(data);
       J=fft2(data);
       %K=fftshift(J);
      %  imshow(log(abs(J)),[]), colormap(jet), colorbar
%        imshow(log(abs(K)),[])
end
end
end
end