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Hello I m using VS2013 and openvc 3.0

I'm trying to convert a image from CV::mat to float* I have found some code snippet but couldn't understand anything.. Here is the code snippet

  `
   #include<iostream>
    #include<opencv2/opencv.hpp>

   using namespace std;
   using namespace cv;

   int main()
  {
        Mat img = imread("foggyHouse.jpg");
        int height = img.rows;
        int width = img.cols;
     //conversion from cv::mat to float*
      float* cpu_image = (float *)malloc((size+1) * 3 * sizeof(float));
       for (int i = 0; i < height; i++)
           {
          for (int j = 0; j < width; j++)
           {
                for (int k = 0; k < 3; k++)
                 {
                   cpu_image[(i * width + j) * 3 + k] = img.at<Vec<float, 3> >(i, j)[k];
                  }
            }
            }

    //converting back from float* cv::mat
    Mat dest(height, width, CV_32FC1, cpu_image);
imwrite("output.jpg",dest);
    return 0;

} ` the problem is I couldn't understand the logic behind the conversion from CV:MAT to float* n vice versa Can anyone explain me??

Hello I m I'm using VS2013 and openvc 3.0

Here I'm trying to read an image, convert a image from CV::mat to float* I have found it to float* from CV::MAT, do some code snippet but couldn't understand anything.. processing, and again convert it back to CV::MAT from float* Here is the code snippet

  `
   #include<iostream>
    #include<opencv2/opencv.hpp>

   using namespace std;
   using namespace cv;

   int main()
  {
        Mat img { 
        //read the image
        Mat src = imread("foggyHouse.jpg");
        int height = img.rows;
        int width = img.cols;
     //conversion from cv::mat to float*
      float* cpu_image = (float *)malloc((size+1) * 3 * sizeof(float));
       for (int i = 0; i < height; i++)
           {
          for (int j = 0; j < width; j++)
           {
                for (int k = 0; k < 3; k++)
                 {
                   cpu_image[(i * width + j) * 3 + k] = img.at<Vec<float, 3> >(i, j)[k];
                  }
            }
            }

    //converting 
       //convert to float*
        Mat dst;
    src.convertTo(dst, CV_32F);
        float *data = dst.ptr<float>();

       //convert back from float* cv::mat
    Mat dest(height, width, CV_32FC1, cpu_image);
imwrite("output.jpg",dest);
to CV::MAT from float*
       Mat dest;
   dst.convertTo(dest,CV_8U);

      //print image
       imwrite("IMg.jpg", dest);

    return 0;

} ` the problem is I couldn't understand the logic behind the conversion I'm getting an error saying

First-chance exception at 0x528E0A14 (opencv_world300.dll) in Project3.exe: 0xC0000005: Access violation reading location 0x00137000. Unhandled exception at 0x528E0A14 (opencv_world300.dll) in Project3.exe: 0xC0000005: Access violation reading location 0x00137000.

i tried other method to convert from CV:MAT to float* here is the code

int height = src.rows;
int width = src.cols;

   //convert from CV::MAT to float*
Mat dst;
src.convertTo(dst, CV_32F);
float *data = dst.ptr<float>();

    //convert from float* n vice versa
Can anyone explain me?? to CV::MAT
    Mat dest(height, width, CV_32FC1, data);
imwrite("IMg.jpg", dest);

this is also giving the same error

Any suggestion or help will be appreciated.

Thanks

Hello I'm using VS2013 and openvc 3.0

Here I'm trying to read an image, convert it to float* from CV::MAT, do some processing, and again convert it back to CV::MAT from float* Here is the code snippet

  `
   #include<iostream>
    #include<opencv2/opencv.hpp>

   using namespace std;
   using namespace cv;

   int main()
  { 
        //read the image
        Mat src = imread("foggyHouse.jpg");

       //convert to float*
        Mat dst;
    src.convertTo(dst, CV_32F);
        float *data = dst.ptr<float>();

       //convert back to CV::MAT from float*
       Mat dest;
   dst.convertTo(dest,CV_8U);

      //print image
       imwrite("IMg.jpg", dest);

    return 0;
 }

} ` the problem is I'm getting an error saying

First-chance exception at 0x528E0A14 (opencv_world300.dll) in Project3.exe: 0xC0000005: Access violation reading location 0x00137000. Unhandled exception at 0x528E0A14 (opencv_world300.dll) in Project3.exe: 0xC0000005: Access violation reading location 0x00137000.

i tried other method to convert from CV:MAT to float* here is the code

int height = src.rows;
int width = src.cols;

   //convert from CV::MAT to float*
Mat dst;
src.convertTo(dst, CV_32F);
float *data = dst.ptr<float>();

    //convert from float*  to CV::MAT
    Mat dest(height, width, CV_32FC1, data);
imwrite("IMg.jpg", dest);

this is also giving the same error

Any suggestion or help will be appreciated.

Thanks

Hello I'm using VS2013 and openvc 3.0

Here I'm trying to read an image, convert it to float* from CV::MAT, do some processing, and again convert it back to CV::MAT from float* Here is the code snippet

  `
   #include<iostream>
    #include<opencv2/opencv.hpp>

   using namespace std;
   using namespace cv;

   int main()
  { 
        //read the image
        Mat src = imread("foggyHouse.jpg");

       //convert to float*
        Mat dst;
    src.convertTo(dst, CV_32F);
        float *data = dst.ptr<float>();

       //convert back to CV::MAT from float*
       Mat dest;
   dst.convertTo(dest,CV_8U);

      //print image
       imwrite("IMg.jpg", dest);

    return 0;
 }

` the problem is I'm getting an error saying

First-chance exception at 0x528E0A14 (opencv_world300.dll) in Project3.exe: 0xC0000005: Access violation reading location 0x00137000. Unhandled exception at 0x528E0A14 (opencv_world300.dll) in Project3.exe: 0xC0000005: Access violation reading location 0x00137000.

i tried other method to convert from CV:MAT to float* here is the code

int height = src.rows;
int width = src.cols;

   //convert from CV::MAT to float*
Mat dst;
src.convertTo(dst, CV_32F);
float *data = dst.ptr<float>();

    //convert from float*  to CV::MAT
    Mat dest(height, width, CV_32FC1, data);
imwrite("IMg.jpg", dest);

this is also giving the same error

Any suggestion or help will be appreciated.

Thanks