clear,close all H=zeros(8,8); BLOCK1=zeros(20,20); RGB=imread('D:\pepersone.jpg'); I=rgb2gray(RGB);

Question

clear,close all
H=zeros(8,8);
BLOCK1=zeros(20,20);
RGB=imread('D:\pepersone.jpg');
I=rgb2gray(RGB);
figure(1);imshow(I);title('原灰度图像');
I=double(I)/256;
I2=imcrop(I,[100 100 255 255]);
figure(2);imshow(I2);title('剪切后图像');
figure(3);imhist(I2);title('原直方图');
I3=imadjust(I2,[0.071 0.91],[0 1]);
figure(4);imhist(I3);title('调整后直方图');
figure(5);imshow(I3);title('调整后剪切图像');
W=imread('D:\watermark.bmp');
figure(6);imshow(W);title('原水印图像');
W=imresize(W,[50,50]);
figure(7);imshow(W);title('调整后水印图像');
%嵌入水印
for p=1:32
for q=1:32
x=(p-1)*8+1;y=(q-1)*8+1;
block3=I3(x:x+8-1,y:y+8-1);
block3=dct(block3);
if W(p,q)==0
a=-1;
else
a=1;
end
block3(1,1)=block3(1,1)*(1+a*0.005);
block3=idct(block3);
I5(x:x+8-1,y:y+8-1)=block3;
end
end
figure(8);imshow(I5,[]);title('嵌入水印后图像');
%压缩
imwrite(I5,'embedded.bmp','bmp');
L=imread('embedded.bmp');
imwrite(L,'attack.jpg','jpeg','Quality',100);
I5=imread('attack.jpg','jpeg');
subplot(3,2,5);figure(9);imshow(I5);title('压缩后的图像');
%提取水印
for p=1:32
for q=1:32
x=(p-1)*8+1;y=(q-1)*8+1;
if (I5(x,y)-I3(x,y))>0
H(p,q)=1;
else
H(p,q)=0;
end
end
end
figure(10);imshow(H,[]);title('提取的水印');

是基于DCT的数字水印，报错是??? Index exceeds matrix dimensions.

求帮助~~~太谢谢你啦~
没分了，希望你能帮帮我~

Answer 1

1