给图片加上数字盲水印的方法

%%傅里叶变换加水印源代码 %% 运行环境Matlab2010a clc;clear;close all; alpha = 1; %% read data im = double(imread('gl1.jpg'))/255; mark = double(imread('watermark.jpg'))/255; figure, imshow(im),title('original image'); figure, imshow(mark),title('watermark'); %% encode mark imsize = size(im); %random TH=zeros(imsize(1)*0.5,imsize(2),imsize(3)); TH1 = TH; TH1(1:size(mark,1),1:size(mark,2),:) = mark; M=randperm(0.5*imsize(1)); N=randperm(imsize(2)); save('encode.mat','M','N'); for i=1:imsize(1)*0.5 for j=1:imsize(2) TH(i,j,:)=TH1(M(i),N(j),:); end end % symmetric mark_ = zeros(imsize(1),imsize(2),imsize(3)); mark_(1:imsize(1)*0.5,1:imsize(2),:)=TH; for i=1:imsize(1)*0.5 for j=1:imsize(2) mark_(imsize(1)+1-i,imsize(2)+1-j,:)=TH(i,j,:); end end figure,imshow(mark_),title('encoded watermark'); %imwrite(mark_,'encoded watermark.jpg'); %% add watermark FA=fft2(im); figure,imshow(FA);title('spectrum of original image'); FB=FA+alpha*double(mark_); figure,imshow(FB); title('spectrum of watermarked image'); FAO=ifft2(FB); figure,imshow(FAO); title('watermarked image'); %imwrite(uint8(FAO),'watermarked image.jpg'); RI = FAO-double(im); figure,imshow(uint8(RI)); title('residual'); %imwrite(uint8(RI),'residual.jpg'); xl = 1:imsize(2); yl = 1:imsize(1); [xx,yy] = meshgrid(xl,yl); figure, plot3(xx,yy,FA(:,:,1).^2+FA(:,:,2).^2+FA(:,:,3).^2),title('spectrum of original image'); figure, plot3(xx,yy,FB(:,:,1).^2+FB(:,:,2).^2+FB(:,:,3).^2),title('spectrum of watermarked image'); figure, plot3(xx,yy,FB(:,:,1).^2+FB(:,:,2).^2+FB(:,:,3).^2-FA(:,:,1).^2+FA(:,:,2).^2+FA(:,:,3).^2),title('spectrum of watermark'); %% extract watermark FA2=fft2(FAO); G=(FA2-FA)/alpha; GG=G; for i=1:imsize(1)*0.5 for j=1:imsize(2) GG(M(i),N(j),:)=G(i,j,:); end end for i=1:imsize(1)*0.5 for j=1:imsize(2) GG(imsize(1)+1-i,imsize(2)+1-j,:)=GG(i,j,:); end end figure,imshow(GG);title('extracted watermark'); %imwrite(uint8(GG),'extracted watermark.jpg'); %% MSE and PSNR C=double(im); RC=double(FAO); MSE=0; PSNR=0; for i=1:imsize(1) for j=1:imsize(2) MSE=MSE+(C(i,j)-RC(i,j)).^2; end end MSE=MSE/360.^2; PSNR=20*log10(255/sqrt(MSE)); MSE PSNR %% attack test %% attack by smearing %A = double(imread('gl1.jpg')); %B = double(imread('attacked image.jpg')); attack = 1-double(imread('attack.jpg'))/255; figure,imshow(attack); FAO_ = FAO; for i=1:imsize(1) for j=1:imsize(2) if attack(i,j,1)+attack(i,j,2)+attack(i,j,3)>0.5 FAO_(i,j,:) = attack(i,j,:); end end end figure,imshow(FAO_); %extract watermark FA2=fft2(FAO_); G=(FA2-FA)*2; GG=G; for i=1:imsize(1)*0.5 for j=1:imsize(2) GG(M(i),N(j),:)=G(i,j,:); end end for i=1:imsize(1)*0.5 for j=1:imsize(2) GG(imsize(1)+1-i,imsize(2)+1-j,:)=GG(i,j,:); end end figure,imshow(GG);title('extracted watermark'); %% attack by cutting s2 = 0.8; FAO_ = FAO; FAO_(:,s2*imsize(2)+1:imsize(2),:) = FAO_(:,1:int32((1-s2)*imsize(2)),:); figure,imshow(FAO_); %extract watermark FA2=fft2(FAO_); G=(FA2-FA)*2; GG=G; for i=1:imsize(1)*0.5 for j=1:imsize(2) GG(M(i),N(j),:)=G(i,j,:); end end for i=1:imsize(1)*0.5 for j=1:imsize(2) GG(imsize(1)+1-i,imsize(2)+1-j,:)=GG(i,j,:); end end figure,imshow(GG);title('extracted watermark'); %%小波变换加水印，解水印大家按照加的思路逆过来就好 clc;clear;close all; %% read data im = double(imread('gl1.jpg'))/255; mark = double(imread('watermark.jpg'))/255; figure, imshow(im),title('original image'); figure, imshow(mark),title('watermark'); %% RGB division im=double(im); mark=double(mark); imr=im(:,:,1); markr=mark(:,:,1); img=im(:,:,2); markg=mark(:,:,2); imb=im(:,:,3); markb=mark(:,:,3); %% parameter r=0.04; g = 0.04; b = 0.04; %% wavelet tranform and add watermark % for red [Cwr,Swr]=wavedec2(markr,1,'haar'); [Cr,Sr]=wavedec2(imr,2,'haar'); % add watermark Cr(1:size(Cwr,2)/16)=... Cr(1:size(Cwr,2)/16)+r*Cwr(1:size(Cwr,2)/16); k=0; while k<=size(Cr,2)/size(Cwr,2)-1 Cr(1+size(Cr,2)/4+k*size(Cwr,2)/4:size(Cr,2)/4+... (k+1)*size(Cwr,2)/4)=Cr(1+size(Cr,2)/4+... k*size(Cwr,2)/4:size(Cr,2)/4+(k+1)*size(Cwr,2)/4)+... r*Cwr(1+size(Cwr,2)/4:size(Cwr,2)/2); Cr(1+size(Cr,2)/2+k*size(Cwr,2)/4:size(Cr,2)/2+... (k+1)*size(Cwr,2)/4)=Cr(1+size(Cr,2)/2+... k*size(Cwr,2)/4:size(Cr,2)/2+(k+1)*size(Cwr,2)/4)+... r*Cwr(1+size(Cwr,2)/2:3*size(Cwr,2)/4); Cr(1+3*size(Cwr,2)/4+k*size(Cwr,2)/4:3*size(Cwr,2)/4+... (k+1)*size(Cwr,2)/4)=Cr(1+3*size(Cr,2)/4+... k*size(Cwr,2)/4:3*size(Cr,2)/4+(k+1)*size(Cwr,2)/4)+... r*Cwr(1+3*size(Cwr,2)/4:size(Cwr,2)); k=k+1; end; Cr(1:size(Cwr,2)/4)=Cr(1:size(Cwr,2)/4)+r*Cwr(1:size(Cwr,2)/4); % for green [Cwg,Swg]=WAVEDEC2(markg,1,'haar'); [Cg,Sg]=WAVEDEC2(img,2,'haar'); Cg(1:size(Cwg,2)/16)=... Cg(1:size(Cwg,2)/16)+g*Cwg(1:size(Cwg,2)/16); k=0; while k<=size(Cg,2)/size(Cwg,2)-1 Cg(1+size(Cg,2)/4+k*size(Cwg,2)/4:size(Cg,2)/4+... (k+1)*size(Cwg,2)/4)=Cg(1+size(Cg,2)/4+... k*size(Cwg,2)/4:size(Cg,2)/4+(k+1)*size(Cwg,2)/4)+... g*Cwg(1+size(Cwg,2)/4:size(Cwg,2)/2); Cg(1+size(Cg,2)/2+k*size(Cwg,2)/4:size(Cg,2)/2+... (k+1)*size(Cwg,2)/4)=Cg(1+size(Cg,2)/2+... k*size(Cwg,2)/4:size(Cg,2)/2+(k+1)*size(Cwg,2)/4)+... g*Cwg(1+size(Cwg,2)/2:3*size(Cwg,2)/4); Cg(1+3*size(Cg,2)/4+k*size(Cwg,2)/4:3*size(Cg,2)/4+... (k+1)*size(Cwg,2)/4)=Cg(1+3*size(Cg,2)/4+... k*size(Cwg,2)/4:3*size(Cg,2)/4+(k+1)*size(Cwg,2)/4)+... g*Cwg(1+3*size(Cwg,2)/4:size(Cwg,2)); k=k+1; end; Cg(1:size(Cwg,2)/4)=Cg(1:size(Cwg,2)/4)+g*Cwg(1:size(Cwg,2)/4); % for blue [Cwb,Swb]=WAVEDEC2(markb,1,'haar'); [Cb,Sb]=WAVEDEC2(imb,2,'haar'); Cb(1:size(Cwb,2)/16)+b*Cwb(1:size(Cwb,2)/16); k=0; while k<=size(Cb,2)/size(Cwb,2)-1 Cb(1+size(Cb,2)/4+k*size(Cwb,2)/4:size(Cb,2)/4+... (k+1)*size(Cwb,2)/4)=Cb(1+size(Cb,2)/4+... k*size(Cwb,2)/4:size(Cb,2)/4+(k+1)*size(Cwb,2)/4)+... g*Cwb(1+size(Cwb,2)/4:size(Cwb,2)/2); Cb(1+size(Cb,2)/2+k*size(Cwb,2)/4:size(Cb,2)/2+... (k+1)*size(Cwb,2)/4)=Cb(1+size(Cb,2)/2+... k*size(Cwb,2)/4:size(Cb,2)/2+(k+1)*size(Cwb,2)/4)+... b*Cwb(1+size(Cwb,2)/2:3*size(Cwb,2)/4); Cb(1+3*size(Cb,2)/4+k*size(Cwb,2)/4:3*size(Cb,2)/4+... (k+1)*size(Cwb,2)/4)=Cb(1+3*size(Cb,2)/4+... k*size(Cwb,2)/4:3*size(Cb,2)/4+(k+1)*size(Cwb,2)/4)+... b*Cwb(1+3*size(Cwb,2)/4:size(Cwb,2)); k=k+1; end; Cb(1:size(Cwb,2)/4)=Cb(1:size(Cwb,2)/4)+b*Cwb(1:size(Cwb,2)/4); %% image reconstruction imr=WAVEREC2(Cr,Sr,'haar'); img=WAVEREC2(Cg,Sg,'haar'); imb=WAVEREC2(Cb,Sb,'haar'); imsize=size(imr); FAO=zeros(imsize(1),imsize(2),3); for i=1:imsize(1); for j=1:imsize(2); FAO(i,j,1)=imr(i,j); FAO(i,j,2)=img(i,j); FAO(i,j,3)=imb(i,j); end end figure, imshow(FAO); title('watermarked image');