14. matlab图像处理基础——数字水印置乱、版权保护、视频处理

1、数字水印置乱

clc;
clear all;
o = imread('lena.jpg');
subplot(2,3,1),imshow(o),title('原始图像');
w = imread('shuiyin.png');
subplot(2,3,2),imshow(w),title('原始水印');
[m,n] = size(w);
c = linspace(0,0,m*n);
c(1) = 0.23;
for i = 2:m*n
    c(i) = 1-2*c(i-1)*c(i-1);
end
[cI,b] = sort(c);
w1 = w;
i = 1:m*n;
w1(i) = w(b(i));
subplot(2,3,3),imshow(w1),title('置乱水印');
ow = bitset(o,1,w1);
subplot(2,3,4),imshow(ow),title('含水印图片');
wG = bitget(ow,1);
subplot(2,3,5),imshow(double(wG)),title('提取出来的水印');
wo = w;
wo(b(i)) = wG(i);
subplot(2,3,6),imshow(double(wo)),title('复原后的水印');

2、版权保护

（1）基本原理

（2）matlab实现：

clc;
clear all;
% 读入原始图像和版权图像
o = imread('lena.jpg');
subplot(2,2,1),imshow(o),title('原始图像');
w = imread('shuiyin.png');
subplot(2,2,2),imshow(w),title('版权图像');
% 原始水印大小
[m,n] = size(w);
% 生成位置矩阵
e = linspace(0,0,m*n);
e(1) = 0.53;
for i = 2:m*n
    e(i) = 1-2*e(i-1)*e(i-1);
end
e = mod(fix(e*10000000),4)+1;
% 嵌入版权图像
i = 1:m*n;
ow = o;
ow(i) = bitset(o(i),e(i),w(i));
subplot(2,2,3),imshow(ow),title('含版权图像');
% 根据位置矩阵提取版权图像
wG = w;
wG(i) = bitget(ow(i),e(i));
subplot(2,2,4),imshow(double(wG)),title('提取出来的版权图像');