c - print values of CV_8UC4 matrix type in OpenCV -

i trying print values of matrix taken input image file, of type cv_8uc4. code written below. problem getting values of 48 , 255 whereas expecting values in 2 , 1 or something.does knows why? think printing values in wrong way. there other way print values of cv_8uc4. code is:

cvmat* m1 = cvloadimagem(argv[1], cv_load_image_unchanged); // load matrix image file cv::mat m1cpp(m1); int type = m1cpp.type(); printf( " type %d  ", type );  switch( type ) {   case 24:    printf("\n --> matrix type cv_8u \n");     for( size_t = 0; < 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 cv_8s \n");     for( size_t = 0; < 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 cv_16u \n");     for( size_t = 0; < 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 cv_16s \n");     for( size_t = 0; < 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 cv_32s \n");     for( size_t = 0; < 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 cv_32f \n");     for( size_t = 0; < 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 cv_64f \n");     for( size_t = 0; < 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");   } 

my case coming 24 , getting wired values 48 , 255. there other way print cv_8uc4 values?

access cv_8uc4 matrix properly:

    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];