基于小波分析的二值数字水印.zip_doh2t_二值水印_基于小波分析的二值数字水印_小波水印_鲁棒性分析

clc;clear;close all; I = imread('airplane.jpg'); R=I(:,:,1);G=I(:,:,2);B=I(:,:,3); W=imread('mark.bmp'); % R=W(:,:,1);G=W(:,:,2);B=W(:,:,3); key=2016115139; [h w]=size(W); n=10;a=1;b=2;N=h; subplot(331);imshow(W,[]);title('原始水印'); imgn=zeros(h,w); for i=1:n for y=1:h for x=1:w xx=mod((x-1)+a*(y-1),N)+1; yy=mod(b*(x-1)+(a*b+1)*(y-1),N)+1; imgn(yy,xx)=W(y,x); end end W=imgn; end subplot(332);imshow(imgn,[]);title('置乱加密水印图'); subplot(333);imshow(R,[]);title('R层置乱水印'); subplot(334);imshow(G,[]);title('G层置乱水印'); subplot(335);imshow(B,[]);title('B层置乱水印'); figure('Name','R通道嵌入水印'); [r,PSNR]=watermark_input(R,W,key); figure('Name','G通道嵌入水印'); [g,PSNR]=watermark_input(G,W,key); figure('Name','B通道嵌入水印'); [b,PSNR]=watermark_input(B,W,key); RGB=cat(3,r,g,b); imwrite(uint8(RGB),'wavlet_mark.jpg'); % S=imnoise(RGB,'salt & pepper',0.1); % G=imnoise(RGB,'gaussian',0,0.1); % h=fspecial('gaussian',[3,3],1); % H=imfilter(RGB,h); % for i=1:200 % for j=1:200 % RGB(i,j)=0; % end % end % L=imrotate(RGB,10,'crop'); % subplot(224);imshow(L);title('图像逆时针旋转10°'); I=imread('wavlet_mark.jpg'); W=imread('mark.bmp'); Wa1=watermark_extract(I(:,:,1),key); Wa2=watermark_extract(I(:,:,2),key); Wa3=watermark_extract(I(:,:,3),key); nc1=sum(Wa1(:).*W(:))/sqrt(sum(Wa1(:).^2))/sqrt(sum(W(:).^2)) nc2=sum(Wa2(:).*W(:))/sqrt(sum(Wa2(:).^2))/sqrt(sum(W(:).^2)) nc3=sum(Wa3(:).*W(:))/sqrt(sum(Wa3(:).^2))/sqrt(sum(W(:).^2)) % subplot(221);imshow(W);title('原始水印'); % subplot(336);imshow(Wa1);title(['R层水印，NC=',num2str(nc1)]); % subplot(337);imshow(Wa2);title(['G层水印，NC=',num2str(nc2)]); % subplot(338);imshow(Wa3);title(['B层水印，NC=',num2str(nc3)]); if nc1>0.8 || nc2>0.8 || nc3>0.8 disp('检测无小波二值数字水印') else disp('无小波二值数字水印') end function Wa=watermark_extract(im,key) W=zeros(64,64);n=64;nc=1; im=double(im); [ca1,ch1,cv1,cd1]=dwt2(im,'haar'); [ca2,ch2,cv2,cd2]=dwt2(ca1,'haar'); %从系数中提取水印信息 Wa=W;rng(key);idx=randperm(numel(ca2),numel(Wa)); for i=1:numel(Wa) j=ca2(idx(i)); z=mod(j,n); if z<n/2 Wa(i)=0; else Wa(i)=1; end end end