混沌对图像的置乱

加密函数：

function myencryption
%对图像进行加密，采用置乱的方式
clear;
clc;
%key为加密密钥
%os原始图像的路径
[filename pathname]=uigetfile('*.bmp;*.tiff;*.tif', '读入需要加密的图像'); 
os=[pathname filename]; 
[filename pathname]=uiputfile({'*.bmp';'*.tiff';'*.tif'}, '保存加密后的图像'); 
ozls=[pathname filename]; 
% key=0.98;
%%%%%%%%%%%%读入混沌初始值
prompt={'混沌初始值 '};
myTitle='initial value';
lines=1;
def={'98'};
mya=inputdlg(prompt,myTitle,lines,def,'on');
key11=['0.',mya{1}];
key=str2num(key11);
%%%%%%%%%%%%
o=imread(os);
% figure,imshow(o);
%计算原始图像的大小
[m n]=size(o);
%l=zeros(m,n);
l=linspace(0,0,m*n);
l(1)=key;
for i=2:m*n
    l(i)=1-2*l(i-1)*l(i-1);
end
% %对生成的混沌序列进行排序
% [lsort lindex]=sort(l);
% t=linspace(0,0,m*n);
% t(1)=0.98;
% for i=1:m*n
%     t(i+1)=1-2*t(i)*t(i);
% end
% for i=1:m*n
%     if (l(i)>=0)
%         l(i)=1;
%     else
%         l(i)=0;
%     end
% end
% l=~l;
% subplot(2,2,2),imshow(l),title('混沌图像');
[lsort,lindex]=sort(l);
%ozl =original zhi luan 表示置乱后的原始图像
ozl=zeros(m,n);
for i=1:m*n
    ozl(i)=o(lindex(i));
end
% ozl=reshape(ozl,m,n);
%%oo =original fu yuan
% ofy=zeros(m,n);
% for i=1:m*n
%     ofy(lindex(i))=ozl(i);
% end
% h= waitbar(0,'程序处理中，请耐心等待。。。');
% for i=1:100, % computation here %
% waitbar(i/100)
% end
% close(h) ;
%首先保存需要加密的图像
ozl=uint8(ozl);
ozl=double(ozl);
imwrite(ozl,ozls);
subplot(1,2,1)
imshow(o)
% title('原始图像')
set(gca,'Title',text('String','原始图像')) 
subplot(1,2,2),imshow(ozl,[]);
set(gca,'Title',text('String','加密后图像')) 
% title('加密后图像');
% [filename pathname]=uiputfile({'*.bmp';'*.tiff';'*.tif'}, '保存加密后图像'); 
% os=[pathname filename]; 
% % [filename pathname]=uiputfile({'*.bmp';'*.tiff';'*.tif'}, '保存图像'); 
% % os=[pathname filename]; 
% imwrite(ozl,os);
% subplot(1,3,3),imshow(ofy,[]),title('复原图像');
% [filename pathname]=uiputfile({'*.bmp';'*.tiff';'*.tif'}, '保存加密后的图像'); 
% os=[pathname filename]; 
% %进度条
% % h= waitbar(0,'程序处理中，请耐心等待。。。');
% % for i=1:100, % computation here %
% % waitbar(i/100);
% % end
% % close(h) ;
% ozl=uint8(ozl);
% imwrite(ozl,os);
% figure,imshow(ozl,[]);
% test=imread(os);
% figure,imshow(test,[]);

解密函数：

function mydecryption
%对加密后的图像进行解密
clear;
clc;
% key=0.98
%key为解密密钥
%os原始图像的路径
[filename pathname]=uigetfile('*.bmp;*.tiff;*.tif', '读入需要解密的图像'); 
os=[pathname filename]; 
[filename pathname]=uiputfile({'*.bmp';'*.tiff';'*.tif'}, '保存解密后的图像'); 
ofys=[pathname filename]; 
ozl=imread(os);
%  figure,imshow(ozl,[]);
%%%%%%%%%%%%%设置混沌初始值
prompt={'混沌初始值 '};
myTitle='initial value';
lines=1;
def={'98'};
mya=inputdlg(prompt,myTitle,lines,def,'on');
key11=['0.',mya{1}];
key=str2num(key11);
%%%%%%%%%%%%设置混沌初始值
%计算原始图像的大小
[m n]=size(ozl);
%l=zeros(m,n);
l=linspace(0,0,m*n);
l(1)=key;
for i=2:m*n
    l(i)=1-2*l(i-1)*l(i-1);
end
% %对生成的混沌序列进行排序
% [lsort lindex]=sort(l);
% t=linspace(0,0,m*n);
% t(1)=0.98;
% for i=1:m*n
%     t(i+1)=1-2*t(i)*t(i);
% end
% for i=1:m*n
%     if (l(i)>=0)
%         l(i)=1;
%     else
%         l(i)=0;
%     end
% end
% l=~l;
% subplot(2,2,2),imshow(l),title('混沌图像');
[lsort,lindex]=sort(l);
%ozl =original zhi luan 表示置乱后的原始图像
% ozl=zeros(m,n);
% for i=1:m*n
%     ozl(i)=o(lindex(i));
% end
% ozl=reshape(ozl,m,n);
%%oo =original fu yuan
ofy=zeros(m,n);
for i=1:m*n
    ofy(lindex(i))=ozl(i);
end
% ozl=uint8(ozl);
ozl=double(ozl);
imwrite(ofy,ofys);
h= waitbar(0,'程序处理中，请耐心等待。。。');
for i=1:100, % computation here %
waitbar(i/100)
end
close(h) ;
subplot(1,2,1),imshow(ozl,[]);
%,title('需要解密的图像');
set(gca,'Title',text('String','需要解密的图像')) 
subplot(1,2,2),imshow(ofy,[]);
%,title('解密后图像');
set(gca,'Title',text('String','解密后图像')) 
% [filename pathname]=uiputfile({'*.bmp';'*.tiff';'*.tif'}, '保存加密后图像'); 
% os=[pathname filename]; 
% imwrite(ozl,os);
% subplot(1,3,3),imshow(ofy,[]),title('复原图像');