Page 187 - Algorithm Collections for Digital Signal Processing Applications using MATLAB

176 Chapter 4

In this example length of the audio signal used for hiding binary image
data is 11488 samples. It is repeated 100 times so that the length of the audio
signal becomes 1148800 samples. The size of the Binary image used is
45X45.Binary image is stored at the rate of 1 bit in 256 samples of the audio
signal.

9.2 M-file for Binary Image Watermarking
in the Wavelet Domain of the Audio Signal

___________________________________________________________

audiowatermarkdb4gv.m

A= wavread ('C:\WINDOWS\Media\Microsoft Office 2000\glass.wav');
A=repmat(A,100,1);
A=A';
len=fix(length(A)/256);
for k=1:1:len-1
temp=A((k-1)*256+1:1:(k-1)*256+256);
col{k}=daub4water(temp);
end
I=imread('BINIMAGE.bmp');
I=I(1:1:45,1:1:45);
I=reshape(I,1,45*45);

for k=1:1:length(I)
switch I(k)
case 0
temp=col{k}{2}{3};
e=sum(temp.^2)/5;
m=mean(temp);
v=var(temp);
col{k}{2}{3}=meanvarnorm(temp,(m-e),v);
case 1
temp=col{k}{2}{3};
e=sum(temp.^2)/5;
m=mean(temp);
v=var(temp);
col{k}{2}{3}=meanvarnorm(temp,(m+e),v);
end
end