一个音频水印的小例子

clc; clear all;close all;
x = ‘classical.00000.wav’;
y = ‘昆.bmp’;
%%%%%----编码–交织
w=imread(y);
w1=w(😃; %降维

%%%%%%%%确定嵌入位置
[a,fs]=audioread(x);

%对音频分帧
win=256;
signal = enframe(a,win);
%dwt
for i = 1:length(signal(:,1))
[c,l] = wavedec(signal(i,:),3,‘haar’);
ca3(i,:)= appcoef(c,l,‘haar’,3); %3阶低频系数
cd3(i,:) = detcoef(c,l,3); %3阶高频系数
cd2(i,:) = detcoef(c,l,2); %2阶高频系数
cd1(i,:) = detcoef(c,l,1); %1阶高频系数
end

[m,n] = size(ca3); %查看矩阵A的大小
%%%离散余弦变换
for i =1:m
cc(i,:) = dct(ca3(i,:));
end
q=0.5;
vv1=[];
for i=1:length(w1)
[S1,V1,D1]=svd(cc(i,:));
vv1=[vv1,V1(1)];
V1(1)=V1(1)+w1(i)q;
cc(i,:)=S1V1D1’;
end
%%进行逆离散余弦变换
for i = 1:m
CC(i,:) = idct(cc(i,:));
end<