function hide()
mm=input('please input the lock password:');
B=imread('E:\chan\mat\gh7.jpg','jpg');
imshow(B);pause;close;
[Bx,By,Bz]=size(B);
CC=imread('E:\chan\mat\wsq.bmp','bmp');
imshow(CC);pause;close;
[Cx,Cy,Cz]=size(CC);
%%密碼分解
m(1)=fix(mm/1000);
m(2)=fix((mm-m(1)*1000)/100);
m(3)=fix((mm-m(1)*1000-m(2)*100)/10);
m(4)=mm-m(1)*1000-m(2)*100-m(3)*10;
m=m.*10
%%構建C
for i=8:5
    C(i)=bitget(CC,i); 
    C1=zeros(Cx,m(9-i),Bz);
    C(i)=[C1,C(i)];
    C2=zeros(m(9-i),m(9-i)+Cy,Bz);
    C(i)=[C2;C(i)];
    CC1=zeros(Bx-Cx-m(9-i),Cy+m(9-i),Bz);
    C(i)=[C(i);CC1];
    CC2=zeros(Bx,By-Cy-m(9-i),Bz);
    C(i)=[C(i),CC2].*2^i;   
    C(i)=uint8(C(i));
    imshow(C(i));pause;close;
end

%%隱藏
D=bitand(B,240);
for i=1:4
    bb(i)=bitget(B,i);
    bb(i,((m(i)+1):(m(i)+Cx)),((m(i)+1):(m(i)+Cy)),1:Bz)=bitand(bb(i,((m(i)+1):(m(i)+Cx)),((m(i)+1):(m(i)+Cy)),1:Bz),240);
    c=bitshift(bitand(C(9-i),240),-4);
    DD(i)=bitor(b,c);
    D=D+DD(i).*2^i;
end
    imshow(D);pause;close;
    imwrite(D,'E:\chan\mat\d.bmp')
    D=imread('E:\chan\mat\d.bmp','bmp');
%%輸解碼
n=input('please input the unlock password:');
for i=1:100000
    if n==m
        break
    else
        sprintf('put the wrong unlock password!!!')
        n=input('please input the correct unlock password:');
    end
end
%%提取
n1=fix(n/100);  
n2=n-(fix(n/100))*100;
U=bitshift((bitand(D,15)),4);
U=U((n1+1):(n1+Cx),(n2+1):(n2+Cy),1:Cz);
imwrite(U,'E:\chan\mat\e.bmp')
imshow(U);pause;close;
sprintf('ok')