将OpenCV Mat与标量元素进行比较

Question

我有cv::Mat A,有CV_32F.但它保存整数值,如1,2 .... 100.我想形成一个大小相同的面具A.

但是如果A(x,y)不等于5(假设),则掩码必须包含零.如果A(x,y)等于5(假设),则掩码必须包含1.

我想稍后将其用作ROI.

Answer 1

// you will have a much simpler construct, 
// this is just for demonstration
Mat_<float> A(3,3); mf << 1,5,5,2,5,5,1,2,3;

// now use a simple MatExpr to get a mask:
Mat mask = (A == 5);

// show results:
cerr << A << endl;
cerr << mask << endl;

------------------------------

[1, 5, 5;
  2, 5, 5;
  1, 2, 3]
[0, 255, 255;
  0, 255, 255;
  0, 0, 0]