clear
clc
close all
a=imread('d:\于秀明1031001755\Miss.bmp');
subplot(231);
imshow(a);
title('256*256');
%圖象128*128
a=double(a);
 for i=1:128;
   for j=1:128;
        b(i,j)=a(2*i,2*j);
    end
end
subplot(232);
imshow(b,[]);
title('128*128');
%圖象64*64
for i=1:64;
    for j=1:64;
        c(i,j)=a(4*i,4*j);
    end
end
subplot(233);
imshow(c,[]);
title('64*64');
%圖象32*32
for i=1:32;
    for j=1:32;
        d(i,j)=a(8*i,8*j);
    end
end
subplot(234);
imshow(d,[]);
title('32*32');
%圖象16*16
for i=1:16;
    for j=1:16;
        e(i,j)=a(16*i,16*j);
    end
end
subplot(235);
imshow(e,[]);
title('16*16');
%圖象8*8
for i=1:8;
    for j=1:8;
        f(i,j)=a(32*i,32*j);
    end
end
subplot(236);
imshow(f,[]);
title('8*8');