extrack.m

ICA是比较新的用于图像水印的方法

%----提取水印---------------------------------------------------------------
%---step---直接计算ICs------------------------------------------------------
S_CI_=DvdBptSubBp(A,k,l);
%--------------------------------------------------------------------------

%得到ICs-------------------------------------------------------------------
icasig_=W_matrix*S_CI_;
index_=max_cov(icasig_);
Y_=[icasig_(index_,:)
    y2];


Y_
%--------------------------------------------------------------------------
[Wartermark] = FASTICA (Y_);
Wartermark
Wartermark=abs(Wartermark);
WWW=ones(k,l);             %这个矩阵来存储水印
if mean( Wartermark(2,:))<mean( Wartermark(1,:))
    mmm=Wartermark(2,:);
else mmm=Wartermark(1,:);
end
%选取第均值最小的独立分量 我们认为它就是水印
for i=1:l
    WWW(:,i)=(  mmm((i-1)*k+1:i*k) )';
end
%--------------------------------------------------------------------------
for i=1:l
    for j=1:k
    if WWW(j,i)<1    WWW(j,i)=1;
    else   WWW(j,i)=0;
    end
    end
end
imshow(WWW);