clear all;

Ximage=double(imread('C:\Documents and Settings\xdjsj\My Documents\zyh\program\Lena.jpg'));
Yimage=double(imread('C:\Documents and Settings\xdjsj\My Documents\zyh\program\Monkey.jpg'));
Zimage=double(imread('C:\Documents and Settings\xdjsj\My Documents\zyh\program\house.jpg'));
Ih=size(Ximage,1);%圖像的長度
Iw=size(Ximage,2);%圖像的寬度
Image=double(zeros(size(Ximage)));
Image=Zimage;
Dimage=Image;
X1image=Ximage;
Y1image=Yimage;

ZHimage=double(zeros(size(Ximage)));
Arnold=double(zeros(size(Ximage)));
s=1;
renewing=0;
hiding=0;
                            %                     隱                   藏
% key1=4.0;
key2=0.1;

for(t=1:s)
figure(t)
subplot(3,2,1)
imshow(Ximage,[]);;%顯示圖像
title('待隱藏圖像1');
for(i=1:Ih)
    for(j=1:Iw)
        Arnold(i,j)=mod(j+i-1,256);
        if(mod(j+i-1,256)==0)
            Arnold(i,j)=256;
        end
        
    end
end

Ximage= Ximage*Arnold; 

figure(t)
subplot(3,2,2)
imshow(Ximage,[]);
title('置亂圖像');

figure(t)
subplot(3,2,3)
imshow(Yimage,[]);
title('待隱藏圖像2');

Yimage= mod(Yimage*Arnold,256); 

figure(t)
subplot(3,2,4)
imshow(Yimage,[]);
title('置亂圖像');
end
%                                    恢                            復
Arnold1= inv(Arnold);
for(t=1:s)
Ximage=Ximage*Arnold1;
Yimage=mod(Yimage*Arnold1,256);

figure(t)
subplot(3,2,5)
imshow(Ximage,[]);
title('恢復圖像');

figure(t)
subplot(3,2,6)
imshow(Yimage,[]);
title('恢復圖像');
end

for(i=1:Ih)
        for(j=1:Iw)
%             if(Image(i,j)~=Ximage(i,j))
                renewing=renewing+(X1image(i,j)-Ximage(i,j))^2;
%             end
        end
    end
    
   renewing=renewing/(Ih*Iw);
   renewing=renewing^(1/2);