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我正在尝试打印从图像文件中获取的矩阵的值，该文件的类型为 CV_8UC4。我的代码写在下面。我的问题是我只得到 48 和 255 的值，而我期望值 2 和 1 或其他值。有人知道为什么吗？我认为我以错误的方式打印值。有没有其他方法可以打印 CV_8UC4 的值。我的代码是：

CvMat* m1 = cvLoadImageM(argv[1], CV_LOAD_IMAGE_UNCHANGED); // load the matrix from an image file
cv::Mat m1cpp(m1);
int type = m1cpp.type();
printf( " type is %d  ", type );

switch( type ) {

 case 24:
   printf("\n --> Matrix type is CV_8U \n");

   for( size_t i = 0; i < m1cpp.rows; i++ ) {
     for( size_t j = 0; j < m1cpp.cols; j++ ) {
       printf( " %d  ", m1cpp.at<uchar>(i,j) );
     } printf("\n");
   }
 break;


 case 25:
   printf("\n --> Matrix type is CV_8S \n");

   for( size_t i = 0; i < m1cpp.rows; i++ ) {
     for( size_t j = 0; j < m1cpp.cols; j++ ) {
       printf( " %d  ", m1cpp.at<schar>(i,j) );
     } printf("\n");
   }
 break;


 case 18:
   printf("\n --> Matrix type is CV_16U \n");

   for( size_t i = 0; i < m1cpp.rows; i++ ) {
     for( size_t j = 0; j < m1cpp.cols; j++ ) {
       printf( " %d  ", m1cpp.at<ushort>(i,j) );
     } printf("\n");
   }
 break;


 case 27:
   printf("\n --> Matrix type is CV_16S \n");

   for( size_t i = 0; i < m1cpp.rows; i++ ) {
     for( size_t j = 0; j < m1cpp.cols; j++ ) {
       printf( " %d  ", m1cpp.at<short>(i,j) );
     } printf("\n");
   }
 break;


 case 28:
   printf("\n --> Matrix type is CV_32S \n");

   for( size_t i = 0; i < m1cpp.rows; i++ ) {
     for( size_t j = 0; j < m1cpp.cols; j++ ) {
       printf( " %d  ", m1cpp.at<int>(i,j) );
     } printf("\n");
   }
 break;

 case 29:
   printf("\n --> Matrix type is CV_32F \n");

   for( size_t i = 0; i < m1cpp.rows; i++ ) {
     for( size_t j = 0; j < m1cpp.cols; j++ ) {
       printf( " %.3f  ", m1cpp.at<float>(i,j) );
     } printf("\n");
   }
 break;


 case 30:
   printf("\n --> Matrix type is CV_64F \n");

   for( size_t i = 0; i < m1cpp.rows; i++ ) {
     for( size_t j = 0; j < m1cpp.cols; j++ ) {
       printf( " %.3f  ", m1cpp.at<double>(i,j) );
     } printf("\n");
   }
  break;

   default:
printf("\n --> Matrix type not found \n");

 }

我的情况是 24，我得到的有线值是 48 和 255。还有其他方法可以打印 CV_8UC4 值吗？

4

1 回答 1

5

正确访问您的CV_8UC4矩阵：

    image.at<cv::Vec4b>(j,i)[0];
    image.at<cv::Vec4b>(j,i)[1];
    image.at<cv::Vec4b>(j,i)[2];
    image.at<cv::Vec4b>(j,i)[3];
于 2013-07-19T08:52:17.527 回答