MATLAB HL子带水印嵌入算法：wm_type_0 函数详解

function loca = wm_type_0(loca,w,step,g) %此函数用于在HL子带嵌入水印 %输入：loca为要嵌入水印的子带 %输出：loca为嵌入水印后的子带

[m2,n2] = size(loca); index = 1; %取出22的块 for k = 1:2:m2-1 for kk = 1:2:n2-1 tem = loca(k:k+1,kk:kk+1); a11 = tem(1,1); a12 = tem(1,2); a21 = tem(2,1); a22 = tem(2,2); if 0 == w(index)
for s = step:step:100step if a11-a12<=g %如果满足条件，a11增，a21减 a11 = a11 + s; a12 = a12 - s; else break; %不满足条件，跳出此循环 end end %-----如果a21和a22不满足条件，则也要调整------------ if a21-a22<=g a21 = a21 + s; a22 = a22 - s; end tem(1,1) = a11; tem(1,2) = a12; tem(2,1) = a21; tem(2,2) = a22; loca(k:k+1,kk:kk+1) = tem; end if 1 == w(index)
for s = step:step:100*step if a11-a12>=-g %如果满足条件，a11增，a21减 a11 = a11 - s; a12 = a12 + s; else break; %不满足条件，跳出此循环 end end %-----如果a21和a22不满足条件，则也要调整------------

    end
    index = index + 1;        
    tem(1,1) = a11;
    tem(1,2) = a12;
    tem(2,1) = a21;
    tem(2,2) = a22;
    loca(k:k+1,kk:kk+1) = tem;        
end    

end