result.m

音频文件的RS分析

%RS检测函数
%输入：[图像矩阵，像素点数]
%输出：估计嵌入率 p

function p = Result(x,bufsize)
%初始化系数
R1 = 0;S1 = 0;U1 = 0;
R2 = 0;S2 = 0;U2 = 0;
R3 = 0;S3 = 0;U3 = 0;
R4 = 0;S4 = 0;U4 = 0;
%计算系数 R S
[R1,S1,U1,R2,S2,U2]=RS_base(x,bufsize);
y=Fadd(x);
[R3,S3,U3,R4,S4,U4]=RS_base(y,bufsize);
%计算d0,dn0,d1,dn1
d0 = R1*4/bufsize - S1*4/bufsize;
dn0 = R2*4/bufsize - S2*4/bufsize;
d1 = R3*4/bufsize - S3*4/bufsize;
dn1 = R4*4/bufsize - S4*4/bufsize;
%d0,dn0,d1,dn1
%解方程
coef = [2*(d1+d0) (dn0-dn1-d1-d0*3) (d0-dn0)];
%coef
r = roots(coef);
i = find(abs(r) == min(abs(r))); %取绝对值较小的解
%计算嵌入率p
p = r(i)/(r(i)-0.5);