水印代码

clear all;

%logistic序列生成算法

figure(1);

an=linspace(3.1,3.99,400);

hold on;box on;axis([min(an),max(an),-1,2]);

N=64*64;

xn=zeros(1,N);

for a=an;

x=rand;

for k=1:20;

x=a*x*(1-x);

end

for k=1:N;

x=a*x*(1-x);

xn(k)=x;

b(k,1)=x;

end

plot(a*ones(1,N),xn,'k.','markersize',1);

end

c=reshape(b,64,64);

%二维矩阵调制

for a1=1:64;

for a2=1:64;

if c(a1,a2)>=0.5;

d(a1,a2)=1;

else d(a1,a2)=0;

end;

end;

end

%水印加密

e=imread('c:\new\123.BMP');

e=double(e);

f=bitxor(d,e);%mm=imread('c:\new\0.BMP');nn=double(mm);%h=bitxor(d,mm); g=bitxor(d,f);

figure(2);

subplot(2,2,1);

imshow(d);title('混沌序列矩阵');

subplot(2,2,2);

imshow(e);title('水印图像');

subplot(2,2,3);

imshow(f);title('混沌加密水印图像');

imwrite(f,'c:\new\0.BMP');

subplot(2,2,4);

imshow(g);title('水印图像恢复');

M=256;

N=64;

[filename1,pathname]=uigetfile('*.*','select the image');

image1=imread(num2str(filename1));

figure(3);subplot(2,2,1);imshow(image1);

title('original image');

image1=double(image1);

subplot(2,2,2);imshow(f);title('original watermark');

%嵌入水印

[ca,ch,cv,cd] = dwt2(image1,'db1');

[cas,chs,cvs,cds] = dwt2(ca,'db1');

for i=1:N

for j=1:N

if f(i,j)==0

a=-1;

else a=1;

end

Ca(i,j)=cas(i,j)*(1+a*0.03);

end

end

IM= idwt2(Ca,chs,cvs,cds,'db1')

markedimage=double(idwt2(IM,ch,cv,cd,'db1'));

subplot(2,2,3);colormap(gray(256));image(markedimage);

title('marked image');

imwrite(markedimage,gray(256),'c:\new\watermarked.bmp','bmp');

%提取水印

image1=imread(num2str(filename1));image1=double(image1); imaged=imread('c:\new\watermarked.bmp');

[ca,ch,cv,cd] = dwt2(image1,'db1');

[cas,chs,cvs,cds]=dwt2(ca,'db1');

[caa,chh,cvv,cdd]=dwt2(imaged,'db1');

[caas,chhs,cvvs,cdds]=dwt2(caa,'db1');

for p=1:N

for q=1:N

a=caas(p,q)/cas(p,q)-1;

if a<0

W(p,q)=0;

else

W(p,q)=255;

end

%频谱

pic1= imread('c:\new\3.jpg');

%pic=rgb2gray(pic);

subplot(2,2,1);

imshow(pic1);

title('原图');

pic_fft1=fft2(double(pic1));

pic_fft1=fftshift(pic_fft1);

subplot(2,2,2);

imshow(log(abs(pic_fft1)),[]);

title('原图频谱图');

end

end

subplot(2,2,4);

colormap(gray(256));image(W);title('从含水印图像中提取的水印'); imwrite(W,gray(256),'watermark.bmp','bmp');

%figure(4);

h=bitxor(d,W);figure(7);subplot(2,2,1);imshow(h);

pic2= imread('c:\new\watermarked.BMP');

%pic=rgb2gray(pic);

subplot(2,2,3);

imshow(pic2);

title('新图');

pic_fft2=fft2(double(pic2));

pic_fft2=fftshift(pic_fft2);

subplot(2,2,4);

imshow(log(abs(pic_fft2)),[]);

title('新图频谱图'

%DWT水印源码

%嵌入源码

clc

clear all;

% 保存开始时间

start_time=cputime;

iTimes=20; %置乱次数

k=20;

blocksize=8; % 设置块的大小

filter_m=[ 1,1,1,1,1,1,1,1; % 滤波矩阵

1,1,1,1,1,1,1,1;

1,1,0,0,0,0,1,1;

1,1,0,0,0,0,1,1;

1,1,0,0,0,0,1,1;

1,1,0,0,0,0,1,1;

1,1,1,1,1,1,1,1;

1,1,1,1,1,1,1,1 ];

% 读入原图像

file_name='_lena_std_bw.bmp';

cover_object=double(imread(file_name));

% 原图像的行数与列数

Mc=size(cover_object,1); %原图像行数

Nc=size(cover_object,2); %原图像列数

% 最大嵌入信息量

max_message=Mc*Nc/(blocksize^2);

% 读入水印图像

file_name='c.bmp';

message=double(imread(file_name));

%%水印图像的行数与列数

Mm=size(message,1); %水印行数Nm=size(message,2); %水印列数% 检查水印信息是否过大

if (Mm*Nm> max_message)

error('水印太大')

end

%对水印图像进行arnold置乱

if Mm~=Nm

error('水印矩阵必须为方阵');

end

if Mm~=40

error('必须为40*40大小,或者修改置乱次数'); end

tempImg=message;

for n=1:iTimes % 次数

for u=1:Mm

for v=1:Nm

temp=tempImg(u,v);

ax=mod((u-1)+(v-1),Mm)+1;

ay=mod((u-1)+2*(v-1),Nm)+1;

outImg(ax,ay)=temp;

end

end

tempImg=outImg;

end

message_vector=reshape(tempImg,1,Mm*Nm);

% 产生watermarked_image,并写入原图信息

watermarked_image=cover_object;

%置随机数发生器的状态为1100

key=1100;

rand('state',key);

% 产生伪随机序列

pn_sequence_zero=round(2*(rand(1,sum(sum(filter_m)))-0.5)); pn_sequence_one=round(2*(rand(1,sum(sum(filter_m)))-0.5)); % 将图像分块嵌入

% 当(2,2) > (2,3) 且message_pad(kk)=0

% 当(2,2) < (2,3) 且message_pad(kk)=1

%%经过分析可以得出结论：在提取水印时，如果cD1(2,2)>cD1(2,3)便是嵌入了水印的黑色像素，

%%反之则是嵌入了白色像素

x=1;

y=1;

h=waitbar(0,'嵌入水印，请等待');

for (kk = 1:length(message_vector))

% 对块进行DWT变换

[cA1,cH1,cV1,cD1] =

dwt2(cover_object(x:x+blocksize-1,y:y+blocksize-1),'haar');

a=cD1;

% 如果message_pad(kk)== 0

if (message_vector(kk) == 0)

% 且(2,2) < (2,3) ，交换它们

if (cD1(2,2) < cD1(2,3))

temp=cD1(2,3);

cD1(2,3)=cD1(2,2);

cD1(2,2)=temp;

end

% 如果message_pad(kk) == 1, elseif (message_vector(kk) == 1)

% 且(2,2) > (2,3) ，交换它们

if (cD1(2,2) >= cD1(2,3))

temp=cD1(2,3);

cD1(2,3)=cD1(2,2);

cD1(2,2)=temp;

end

end

% 检查(2,2) ，(2,3)的差是否>= k if cD1(2,2) > cD1(2,3)

if cD1(2,2) - cD1(2,3) < k

cD1(2,2)=cD1(2,2)+(k/2);

cD1(2,3)=cD1(2,3)-(k/2);

end

else

if cD1(2,3) - cD1(2,2) < k

cD1(2,3)=cD1(2,3)+(k/2);

cD1(2,2)=cD1(2,2)-(k/2);

end

end

%IDWT

watermarked_image(x:x+blocksize-1,y:y+blocksize-1)=

idwt2(cA1,cH1,cV1,cD1,'haar',[Mc,Nc]);

% 移动到下一块

if (x+blocksize) >= Nc

x=1;

y=y+blocksize;

else

x=x+blocksize;

end

waitbar(kk/length(message_vector),h);

end

close(h);

% 转换为uint8并写入dwt_watermarked.bmp

watermarked_image_uint=uint8(watermarked_image);

imwrite(watermarked_image_uint,'dwt_watermarked.bmp','bmp'); % 显示运行时间

elapsed_time=cputime-start_time,

% 显示图像

figure(1)

subplot(2,2,1);

imshow(message,[]);

title('水印');

subplot(2,2,4)

imshow(outImg,[]);

title('置乱水印');

subplot(2,2,2);

imshow(cover_object,[]);

title('原图');

subplot(2,2,3);

imshow(watermarked_image,[]) title('嵌入水印图像')

%DWT源码

%提取源码

clear all;

% 保存开始时间

start_time=cputime;

iTimes=20; %置乱次数

blocksize=8; % 设置块的大小

filter_m=[ 1,1,1,1,1,1,1,1; % 滤波矩阵

1,1,1,1,1,1,1,1;

1,1,0,0,0,0,1,1;

1,1,0,0,0,0,1,1;

1,1,0,0,0,0,1,1;

1,1,0,0,0,0,1,1;

1,1,1,1,1,1,1,1;

1,1,1,1,1,1,1,1 ];

% 读入嵌入水印图像

[filename,pathname]=uigetfile('*.bmp;*tiff;*tif;*jpg','输入嵌有水印的图像'); watermarked_image=double(imread(filename));

% 嵌入水印图像的行数与列数

Mw=size(watermarked_image,1); %嵌入水印图像的行数

Nw=size(watermarked_image,2); %嵌入水印图像的列数

% 最大嵌入信息量

max_message=Mw*Nw/(blocksize^2);

% 读入原始水印

file_name='c.bmp';

orig_watermark=double(imread(file_name));

% 原始水印的行数与列数

Mo=size(orig_watermark,1); %原始水印的行数

No=size(orig_watermark,2); %原始水印的列数

%置随机数发生器的状态为1100

rand('state',1100);

% 产生伪随机序列

pn_sequence_zero=round(2*(rand(1,sum(sum(filter_m)))-0.5));

pn_sequence_one=round(2*(rand(1,sum(sum(filter_m)))-0.5));

% 将图像分块提取水印

x=1;

y=1;

h=waitbar(0,'水印提取中，请等待');

for (kk = 1:max_message)

% 对块进行dwt变换

[cA1,cH1,cV1,cD1] =

dwt2(watermarked_image(x:x+blocksize-1,y:y+blocksize-1),'haar');

% 如果cD1(2,2) > cD1(3,3) 那么message_vector(kk)=0

% 否则message_vector(kk)=1

if cD1(2,2)>cD1(3,3)

message_vector(kk)=0;

else

message_vector(kk)=1;

end

% 移动到下一块

if (x+blocksize) >= Mw

x=1;

y=y+blocksize;

else

x=x+blocksize;

end

waitbar(kk/max_message,h);

end

close(h);

% arnold置乱

tempImg=reshape(message_vector(1:Mo*No),Mo,No); message_arnold=tempImg;

for n=1:iTimes % 次数

for u=1:Mo

for v=1:No

temp=tempImg(u,v);

ax=mod((u-1)+(v-1),Mo)+1;

ay=mod((u-1)+2*(v-1),No)+1;

outImg(ax,ay)=temp;

end

end

tempImg=outImg;

end

message=tempImg;

% 计算运行时间

elapsed_time=cputime-start_time, % 显示提取水印与原始水印

figure(3)

subplot(1,3,1);

imshow(message_arnold,[]);

title('提取的置乱水印');

subplot(1,3,2);

imshow(message,[]);

title('再次置乱后水印');

subplot(1,3,3);

imshow(orig_watermark,[])

title('原始水印');