shuiyin.rar_数字水印

clear M=256; N=256; a=1; p=0.3; A=imread('girl2.tif'); RA=A(:,:,1); GA=A(:,:,2); BA=A(:,:,3); B=imread('bz.tif'); B=rgb2gray(B); B=double(B); RA=double(RA); GA=double(GA); BA=double(BA); for i=1:M/8 for j=1:N/8 RC=RA(((i-1)*8+1):(i*8),((j-1)*8+1):(j*8)); GC=GA(((i-1)*8+1):(i*8),((j-1)*8+1):(j*8)); BC=BA(((i-1)*8+1):(i*8),((j-1)*8+1):(j*8)); D=B(((i-1)*4+1):(i*4),((j-1)*4+1):(j*4)); RE=dct2(RC);GE=dct2(GC);BE=dct2(BC); D=D-128; D1=fix(D/16)-4; D2=fix((D-fix(D/16)*16)/4)-2; D3=D-(D1+4)*16-(D2+2)*4-2; for k=1:8 RE(9-k,k)=RE(9-k,k)*(1+p*D1(k));GE(9-k,k)=GE(9-k,k)*(1+p*D2(k));BE(9-k,k)=BE(9-k,k)*(1+p*D3(k)); end for q=1:7 RE(8-q,q)=RE(8-q,q)*(1+p*D1(q+8));GE(8-q,q)=GE(8-q,q)*(1+p*D2(q+8));BE(8-q,q)=BE(8-q,q)*(1+p*D3(q+8)); end RE(5,5)=RE(5,5)*(1+p*D1(16));GE(5,5)=GE(5,5)*(1+p*D2(16));BE(5,5)=BE(5,5)*(1+p*D3(16)); RF=RE;GF=GE;BF=BE; RG=idct2(RF);GG=idct2(GF);BG=idct2(BF); Rx(((i-1)*8+1):(i*8),((j-1)*8+1):(j*8))=RG(1:8,1:8); Gx(((i-1)*8+1):(i*8),((j-1)*8+1):(j*8))=GG(1:8,1:8); Bx(((i-1)*8+1):(i*8),((j-1)*8+1):(j*8))=BG(1:8,1:8); end end RX=uint8(Rx);GX=uint8(Gx);BX=uint8(Bx); X=cat(3,RX,GX,BX); imwrite(X,'JG.tif','tif'); % 以上为水印的嵌入 % 以下是水印的提取 Y=imread('JG.tif'); RY=Y(:,:,1); GY=Y(:,:,2); BY=Y(:,:,3); I=imread('girl2.tif'); RI=I(:,:,1); GI=I(:,:,2); BI=I(:,:,3); RY=double(RY);GY=double(GY);BY=double(BY); RI=double(RI);GI=double(GI);BI=double(BI); for i=1:M/8 for j=1:N/8 RJ=RI(((i-1)*8+1):(i*8),((j-1)*8+1):(j*8));GJ=GI(((i-1)*8+1):(i*8),((j-1)*8+1):(j*8));BJ=BI(((i-1)*8+1):(i*8),((j-1)*8+1):(j*8)); RH=dct2(RJ);GH=dct2(GJ);BH=dct2(BJ); Ry=RY(((i-1)*8+1):(i*8),((j-1)*8+1):(j*8));Gy=GY(((i-1)*8+1):(i*8),((j-1)*8+1):(j*8));By=BY(((i-1)*8+1):(i*8),((j-1)*8+1):(j*8)); Ry=dct2(Ry);Gy=dct2(Gy);By=dct2(By); for k=1:8 Rz(k)=(Ry(9-k,k)/RH(9-k,k)-1)/p;Gz(k)=(Gy(9-k,k)/GH(9-k,k)-1)/p;Bz(k)=(By(9-k,k)/BH(9-k,k)-1)/p; end for q=1:7 Rz(q+8)=(Ry(8-q,q)/RH(8-q,q)-1)/p;Gz(q+8)=(Gy(8-q,q)/GH(8-q,q)-1)/p;Bz(q+8)=(By(8-q,q)/BH(8-q,q)-1)/p; end Rz(16)=(Ry(5,5)/RH(5,5)-1)/p;Gz(16)=(Gy(5,5)/GH(5,5)-1)/p;Bz(16)=(By(5,5)/BH(5,5)-1)/p; u=(Rz(1:16)+4)*16+(Gz(1:16)+2)*4+Bz(1:16)+2+128; P=reshape(u,4,4); Z(((i-1)*4+1):(i*4),((j-1)*4+1):(j*4))=P(1:4,1:4); end end Z=Z(1:M/2,1:N/2); % MM=B-Z; % MM=uint8(MM); Z=uint8(Z); A=uint8(A); B=uint8(B); imwrite(Z,'SYtwo.tif','tif'); subplot(2,2,1); imshow(A); title('原宿主图像'); subplot(2,2,2); imshow(B); title('水印图像'); subplot(2,2,3); imshow(X); title('嵌入水印后的图像'); subplot(2,2,4); imshow(Z); title('提取的水印图像'); % aaa=aaaa % imshow(MM); % D=213; % D=D-128; % D1=fix(D/16); % D2=fix((D-fix(D/16)*16)/4); % D3=D-D1*16-D2*4; % a=dec2bin(D) % b=dec2bin(D1) % c=dec2bin(D2) % d=dec2bin(D3)