内存位置未处理的异常

Question

我是OpenCV的新手，我正在尝试编写一个简单的代码来获取图像中块大小的均值。我写了下面的代码，构建是好的，但是，调试给了我一个未处理的异常在内存位置。此例外是在以下行：

mean_img.at<double>(i/block_size, j/block_size) = mean_img.at<double>(i/block_size,j/block_size) + new_img.at<double>(i + x, j + y)/(mean); 

因此，如果有人给我一些提示，我将不胜感激。在此先感谢，这里是整个代码：

#include "opencv2/highgui/highgui.hpp" // Include Libs for OpenCV and Image Processing 
#include <opencv2/opencv.hpp> // check that 
#include "opencv2/core/core.hpp" // check that 
#include <iostream> // Include Libs for C++ 
#include "opencv2/imgproc/imgproc.hpp" // Include Libs for OpenCV and Image Processing 
#include <math.h> 

using namespace cv; // namespace parameters not important in OpenCV2.4.6 
using namespace std; // namespace parameters not important in OpenCV2.4.6 

int main(int argc, const char** argv) 
{ 
    /*This part is to compute the parameters(block size, resize parameter) of the new_img*/ 
    int resize_parameter; // resize parameter must be multiplication of 2 
    resize_parameter = 500; 
    int block_size; // block parameter must be divisable by of block size 
    block_size = 50; 
    if ((resize_parameter % 2) != 0) resize_parameter = resize_parameter - (resize_parameter % 2); 
    while ((resize_parameter % block_size) != 0) block_size = block_size - 1; 
    int mean_size = resize_parameter/block_size; // this is the size of the mean matrix 
    int mean = block_size * block_size; // this no is ti get the mean of every element in the matrix 
    //int mean_img [mean_size][mean_size] = {}; // the mean image matrix initialized by zero 
    /*This part is to allocate the array with dynamic size*/ 
    //int** mean_img = new int*[mean_size]; 
    //for(int x = 0; x < mean_size; x++) 
    //mean_img[x] = new int[mean_size]; 
    /*Then we can use the array*/ 
    /*This part is to fill all the elements of the mean matrix with zeros*/ 
    //memset(mean_img, 0, sizeof(mean_img[0][0]) * mean_size * mean_size); 

    /*This part is the definition of the matrices that are used for the images*/ 
    Mat mean_img = Mat(mean_size,mean_size,CV_64FC4, cv::Scalar(0)); // define a new matrix with meansize*meansize elements to compute the mean 
    Mat mean_img_full = Mat(resize_parameter,resize_parameter,CV_64FC4, cv::Scalar(0)); // define a new matrix with resizeparameter*resizeparameter elements to compute the mean 
    Mat new_img = Mat(resize_parameter,resize_parameter,CV_64FC4); // define a new matrix with resize_parameter*resize_parameter elements 
    Mat original_img = imread("Desert.JPG", CV_LOAD_IMAGE_GRAYSCALE); //define a new matrix and read the image data in the file "Desert.JPG" and store it in 'original_img' 
    // notes: the location of the image must be in the same directory of the C++ file 

    if (original_img.empty()) //check whether the image is loaded or not 
    { 
      cout << "Error : Image cannot be loaded..!!" << endl; 
      //system("pause"); //wait for a key press 
      return -1; 
    } 

    // explicitly specify dsize=dst.size(); fx and fy will be computed from that. 
    // resize(src matrix, dst matrix, dst.size to get the size of the dst matrix, 0, 0 "to deal with the dst matrix size, may be 0.5 or any fraction from the src size, "AREA,CUBIC,LINEAR") 
    resize(original_img, new_img, new_img.size(), 0, 0, CV_INTER_AREA); 

    /*This part is to compute the mean of each block*/ 
    for (int i = 0; i < resize_parameter; i = i + block_size) // i represents the index of the raw 
    { 
     for (int j = 0; j < resize_parameter; j = j + block_size) // for the blocks in the same raw with different columns 
     { 
      for (int x = 0; x < block_size; x++) // x represents the index of the raw 
      { 
       for (int y = 0; y < block_size; y++) // y represents the index of the column 
       { 
        //cout << i ; //cout << "\n"; //cout << j ; //cout << "\n"; //cout << x ; //cout << "\n"; //cout << y ; //cout << "\n"; 
        mean_img.at<double>(i/block_size, j/block_size) = mean_img.at<double>(i/block_size,j/block_size) + new_img.at<double>(i + x, j + y)/(mean); 

       } 
      } 
     } 
    } 
    /*This is the end of the part to compute the mean of each block*/ 
    /*This part is to fill all the resize matrix with the mean value*/ 
    for (int x = 0; x < resize_parameter/block_size; x++) // x represents the index of the raw in the mean matrix 
    { 
     for (int y = 0; y < resize_parameter/block_size; y++) // y represents the index of the column in the mean matrix 
     { 
      for (int i = 0; i < block_size; i++) // i represents the index of the raw in the mean_full matrix 
      { 
       for (int j = 0; j < block_size; j++) // j represents the index of the column in the mean_full matrix 
       { 
        mean_img_full.at<double>((x*block_size)+i,(y*block_size)+j) = mean_img.at<double>(x,y); 
       } 
      } 
     } 
    } 
    //cout << cv::getBuildInformation() << endl; 

    /*This is the end of the part to fill all the resize matrix with the mean value*/ 

    namedWindow("OriginalImage", CV_WINDOW_AUTOSIZE); //create a window with the name "OriginalImage" 
    imshow("OriginalImage", original_img); //display the image which is stored in the 'original_img' in the "OriginalImage" window 
    namedWindow("NewImage", CV_WINDOW_AUTOSIZE); //create a window with the name "NewImage" 
    imshow("NewImage", new_img); //display the image which is stored in the 'new_img' in the "NewImage" window 
    namedWindow("MeanImage", CV_WINDOW_AUTOSIZE); //create a window with the name "MeanImage" 
    imshow("MeanImage", mean_img); //display the image which is stored in the 'mean_img' in the "MeanImage" window 
    namedWindow("MeanFullImage", CV_WINDOW_AUTOSIZE); //create a window with the name "MeanFullImage" 
    imshow("MeanFullImage", mean_img_full); //display the image which is stored in the 'mean_img_full' in the "MeanFullImage" window 

    waitKey(0); //wait infinite time for a keypress 
    destroyWindow("OriginalImage"); //destroy the window with the name, "OriginalImage" 
    destroyWindow("NewImage"); //destroy the window with the name, "NewImage" 
    destroyWindow("MeanImage"); //destroy the window with the name, "MeanImage" 
    destroyWindow("MeanFullImage"); //destroy the window with the name, "MeanImage" 
    return 0; 
} 

Answer 1

问题是在每个矩阵的类型的定义。它必须是8位无符号字符。它正在工作。非常感谢,,,