數(shù)字水印-實(shí)驗(yàn)報(bào)告

1、精選優(yōu)質(zhì)文檔-傾情為你奉上精選優(yōu)質(zhì)文檔-傾情為你奉上專心-專注-專業(yè)專心-專注-專業(yè)精選優(yōu)質(zhì)文檔-傾情為你奉上專心-專注-專業(yè)基于DCT變換域的水印嵌入和提取一、原始圖像被隨機(jī)攻擊的源程序：% function random_damage()function random_damage()file_name = tt.jpg;oriwat_img = imread(file_name);% compute the sizeH = size(oriwat_img, 1);W = size(oriwat_img, 2);% 隨機(jī)產(chǎn)生行、列，破壞row1 = unidrnd(512);row2 =

2、unidrnd(512);column1 = unidrnd(512);column2 = unidrnd(512);if(row1 row2) temp = row1; row1 = row2; row2 = temp;endif(column1 column2) temp = column1; column1 = column2; column2 = temp;endattack_img = oriwat_img;for i = row1 : row2 for j = column1:column2 attack_img(i, j) = unidrnd(255); endend% set

3、the attacked imageimwrite(attack_img, muc_attacked.bmp, bmp);count = (column2 - column1 + 1) * (row2 - row1 + 1)subplot(1, 2, 1);imshow(oriwat_img)title(OriginalWatermarked Image)subplot(1, 2, 2);imshow(attack_img)title(Attacked Image)該實(shí)驗(yàn)程序所產(chǎn)生的實(shí)驗(yàn)結(jié)果為：由于該程序是通過(guò)產(chǎn)生隨機(jī)序列而對(duì)圖像進(jìn)行攻擊的，所以所產(chǎn)生的的實(shí)驗(yàn)結(jié)果每次都會(huì)有所不同，而上圖的實(shí)驗(yàn)

4、結(jié)果也是所顯示的幾個(gè)圖像里面被攻擊的效果最明顯程度最嚴(yán)重的一個(gè)。普通水印的嵌入和提取的源程序：M=8; %原圖像長(zhǎng)度N=8; %水印圖像長(zhǎng)度K=8; I=zeros(M,M);J=zeros(N,N);B=zeros(K,K);I=imread(muc.jpg);%讀入原圖像subplot(221)imshow(I);title(原圖像);%顯示水印圖像%randn(seed,10);%mark=randn(1024,1);%subplot(2,2,2);%plot(mark);%title(水印序列);L=imread(c.jpg);J=rgb2gray(L)subplot(2,2,2);i

5、mshow(J);title(水印圖像);%嵌入水印T=1;for m=1:N for n=1:N x=(m-1)*K+1; y=(n-1)*K+1; B=I(x:x+K-1,y:y+K-1); %將原圖分成8*8的子塊 B=dct2(B); %對(duì)子塊進(jìn)行DCT變換 if x=1&y=1 a=0.002; else a=0.5; end B=B*(1+a*mark(T); %嵌入水印 B=idct2(B); %進(jìn)行DCT反變換 I(x:x+K-1,y:y+K-1)=B; T=T+1; endendsubplot(2,2,3);imshow(I);%顯示嵌入水印后的圖像title(嵌入水印后的圖

6、像);imwrite(I,嵌入后的圖像.jpg);%從嵌入水印的圖像中提取水印I=imread(muc.jpg);J=imread(c.jpg);for m=1:N for n=1:N x=(m-1)*K+1; y=(n-1)*K+1; B1=I(x:x+K-1,y:y+K-1); B2=J(x:x+K-1,y:y+K-1); B1=idct2(B1); B2=idct2(B2); a=B2(1,1)/B1(1,1)-1; if a0 W(m,n)=0; else W(m,n)=1; end endend%顯示提取的水印subplot(224)imshow(W);title(從含有水印圖像中提

7、取的水印);該程序運(yùn)行后產(chǎn)生的實(shí)驗(yàn)結(jié)果為： 在這個(gè)程序運(yùn)行之前，有一個(gè)錯(cuò)誤的程序，運(yùn)行的過(guò)程中總是無(wú)法提取出有效的水印，由于算法的不正確,再加上自己之前并沒(méi)有意識(shí)到圖片的大小的問(wèn)題所以總是出現(xiàn)錯(cuò)誤的結(jié)果最終通過(guò)對(duì)算法的改正和圖片大小的修正出現(xiàn)了自己想要的結(jié)果，下圖則是出現(xiàn)錯(cuò)誤的水印，但是我們還是可以通過(guò)這個(gè)錯(cuò)誤的圖像發(fā)現(xiàn)它所實(shí)現(xiàn)的功能里面對(duì)于水印的嵌入還是有著很明顯的效果，只是這樣的結(jié)果又在安全性上大打折扣： 出現(xiàn)錯(cuò)誤的水印提取兩種噪聲加入后的源程序;M=imread(muc.jpg); %讀取原始的圖像 subplot(2,2,1);imshow(M); %顯示原始圖像title(原始圖像)

8、;P1=imnoise(M,gaussian,0.02);%加入高斯躁聲 subplot(2,2,2);imshow(P1); %加入高斯躁聲后顯示圖像 title(加入高斯噪聲圖像);P2=imnoise(M,salt & pepper,0.02) %加入椒鹽躁聲subplot(2,2,3);imshow(P2);%加入椒鹽躁聲后顯示圖像 title( 加入椒鹽噪聲圖像); 該實(shí)驗(yàn)程序運(yùn)行后所執(zhí)行的結(jié)果為：該程序在運(yùn)行過(guò)程中始終很順利，所以對(duì)于實(shí)驗(yàn)結(jié)果的獲得也是顯得很輕松。加入高斯噪聲后的圖像以及從高斯噪聲中提取出水印的源程序：clear all;M =512;N =64;K =8;I=ze

9、ros(M,M);J=zeros(N,N);BLOCK=zeros(K,K);subplot(2,2,1);I=imread(muc.jpg);imshow(I);title(原始圖像);subplot(2,2,2);J=imread(t1.bmp);imshow(J);title (水印圖像);for p=1:N for q=1:N x=(p-1)*K+1; y=(q-1)*K+1; BLOCK=I(x:x+K-1,y:y+K-1);BLOCK=dct2(BLOCK); if J(p,q)=0 a=-1; else a=1; end BLOCK(1,1)=BLOCK(1,1)*(1+a*0.

10、03);BLOCK=idct2(BLOCK); I(x:x+K-1,y:y+K-1)=BLOCK; endendsubplot(2,2,3);imshow(I);title(嵌入水印后的圖像);imwrite(I,watermarked.bmp,bmp);I1=zeros(M,M);J1=zeros(M,M);BLOCK1=zeros(K,K);BLOCK2=zeros(K,K);I1=imread(muc.jpg);J1=imread(watermarked.bmp,bmp);w=zeros(N,N);for p=1:N for q=1:N x=(p-1)*K+1; y=(q-1)*K+1;

11、 BLOCK1 =I1(x:x+K-1,y:y+K-1); BLOCK2 =J1(x:x+K-1,y:y+K-1); BLOCK1=dct2(BLOCK1); BLOCK2=dct2(BLOCK2); a = BLOCK2(1,1)/BLOCK1(1,1)-1; if a0 W(p,q)=0; else W(p,q)=1; end endendsubplot(2,2,4);imshow(W);title(從含水印的圖像中提取的水印);G=imnoise(J1,gaussian,0,0.01);subplot(2,3,5);imshow(G,);title(加入高斯噪聲);w1=zeros(N,

12、N);BLOCK3=zeros(K,K);BLOCK4=zeros(K,K);for p=1:N for q=1:N x=(p-1)*K+1; y=(q-1)*K+1; BLOCK3 =I1(x:x+K-1,y:y+K-1); BLOCK4 =G(x:x+K-1,y:y+K-1); BLOCK3=dct2(BLOCK3); BLOCK4=dct2(BLOCK4); a = BLOCK4(1,1)/BLOCK3(1,1)-1; if a0 W1(p,q)=0; else W1(p,q)=1; end endendsubplot(2,3,6);imshow(W1);title(從含高斯噪聲的水印圖像中提取的水印)