Question

我想在blockproc函数中使用我自己的（自定义）函数。但我无法弄清楚如何真正融入这一点。我是MATLAB的新手。

在这个函数中，我试图将信息（LR_seq的位）嵌入到块中。我在块中一次选择一对像素并尝试将我的信息嵌入其中。

这是我的功能代码：

function dataencode(block_struct,LR_seq)

LR_seq = vec2mat(LR_seq,2,4);%changing it into a 2,4 mat to make it fit into the for loop
LR_mat = zeros(4,4);%adding zero columns in between to convert it into 4,4 mat to fit into the for loop
LR_mat(:,1:2:end) = LR_seq;


for r = 1 : 4

for c = [1  3] 

x = uint16(block_struct.data(r,c)) ; 
y = uint16(block_struct.data(r,c+1));
x1 = de2bi(x,12); y1 = de2bi(y,12);
  if(~(2*x - y == 1) | ~(2*y - x == 1) | ~(2*x - y == 255) | ~(2*y - x == 255))
   if((x1(1) == 0) & (y1(1) == 0))  %because in maltab lsb comes first
     xt = (2*x - y) ; yt = (2*y - x);
       xt_bin = de2bi(xt,12); xt_bin(1) = 1; xtd = bi2de(xt_bin);block_struct.data(r,c) =xtd;
        yt_bin = de2bi(yt,12) ; yt_bin(1) = LR_mat(r,c); ytd = bi2de(yt_bin); block_struct.data(r,c+1) = ytd;
        elseif((x1(1) == 1) | (y1(1) == 1))
          x1(1) = 0 ; xtd = bi2de(x1) ; block.data(r,c) = xtd;
           y1(1) = LR_mat(r,c); ytd = bi2de(y1) ; block_struct.data(r,c+1) = ytd;
          end
         else
    x1(1) = 0; xtd = bi2de(x1) ; block.data(r,c) = xtd;
      ytd = bi2de(y1); block_struct.data(r,c+1) = ytd;
     end
   end
 end
end

M是一个RGB 256x256图像，我希望在其中嵌入比特序列LR_seq。

我试图在命令窗口中调用此函数，但它给了我一个空矩阵，请帮忙。这是我调用函数的代码

 for ii = 1 : 8 : size(LR_seq)
     myfunc = @(block_struct) dataencode(block_struct,LR_seq(ii : ii+7));
     U_im_new = blockproc(M,[4 4],myfunc)
 end

Answer 1

dataencode应该在参数中使用block_struct。但是您的函数myfunc_red使用block_struct的数据调用encode函数。

您可能更喜欢这样做：

myfunc = @(block_struct) dataencode(block_struct,LR_seq(1 : 8));
U_im_r = blockproc(M(:,:,1),[4 4],myfunc);

在Matlab中使用blockproc中的自定义函数

1 个答案: