Mat 矩阵

Mat img_final(2,2,CV_8UC3);
cout<<img_final<<endl;

2.

Mat img_final(2,2,CV_8UC1);
 img_final.cols = 3;
 img_final.rows = 3;
 cout << img_final << endl;

3.

Mat img_final(20,20,CV_8UC1);
 for (int i = 0; i < img_final.rows; i++)
  for (int j = 0; j < img_final.cols; j++)
   img_final.at<uchar>(i, j) = 1;
 img_final.cols = 5;
 img_final.rows = 5;
 cout << img_final;

4.暂时没弄清原理,还请各位不吝赐教

Mat img_final(2, 2, CV_8UC1);
 for (int i = 0; i < img_final.rows; i++)
  for (int j = 0; j < img_final.cols; j++)
   img_final.at<uchar>(i, j) = 1;
 img_final.cols = 3;
 img_final.rows = 3;
 cout << img_final << endl;

 Mat img_final(2, 2, CV_8UC1);
 for (int i = 0; i < img_final.rows; i++)
  for (int j = 0; j < img_final.cols; j++)
   img_final.at<uchar>(i, j) = 1;
 img_final.cols = 4;
 img_final.rows = 4;
 cout << img_final << endl;