how to display images from .csv file using opencv

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Hi... i am trying to display the images from the .csv file. I am a begginer with opencv and c++ concepts, but am uanble to understand the need of some functions ....Here is the code which am trying to figure out.It showing the following error One of arguments' values is out of range (Bad new number of rows) in reshape Someone help me with this problem it wil be a great help.

#include "opencv2/core/core.hpp"
#include "opencv2/highgui.hpp"
#include "opencv2/face.hpp"
#include "opencv2/imgproc.hpp"
#include <iostream>
#include <fstream>
#include <sstream>
using namespace std;
using namespace cv;
using namespace cv::face;

 static Mat norm_0_255(InputArray _src)
 {
 Mat src = _src.getMat();
 Mat dst;
 switch(src.channels())
 {
 case 1:
 cv::normalize(_src, dst, 0, 255, NORM_MINMAX, CV_8UC1);
 break;
 case 2:
 cv::normalize(_src, dst, 0, 255, NORM_MINMAX, CV_8UC3);
 break;
 default:
 src.copyTo(dst);
 break;
 }
 return dst;
 }

 void read_csv(const String filename, vector<Mat> & images,vector<int> & labels, char separator=';')
 {
   std::ifstream myfile(filename.c_str(),ifstream::in);
   if(!myfile)
    {
      string error_message="File does not exist";
      CV_Error(Error::StsBadArg, error_message);
     }
    string line, path,classlabel;
    while(getline(myfile,line))
     {
    stringstream liness(line);
    getline(liness,path,separator);
    getline(liness,classlabel);
    if(!path.empty() && !classlabel.empty())
    {
     images.push_back(imread(path,0));
     labels.push_back(atoi(classlabel.c_str()));
     }
    }
   }
   int main(int argc, const char *argv[])
     {

    if(argc!=2)
        {
      cout<<"usage:"<<"argv[0]"<<"<csv.txt> <output_folder>\n"<<endl;
        return -1;
      }
       string output_folder =".";
       if(argc==3)
        {
         output_folder = String(argv[2]);
         }
        String fn_csv = String(argv[1]);

vector<Mat> images;
vector<int> labels;

try {
    read_csv(fn_csv, images, labels);
} catch (cv::Exception& e) {
    cerr << "Error opening file \"" << fn_csv << "\". Reason: " << e.msg << endl;

    exit(1);
}

if(images.size() <= 1) {
    string error_message = "This demo needs at least 2 images";
    CV_Error(CV_StsError, error_message);
}

int height = images[0].rows;

Mat testSample = images[images.size() - 1];
int testLabel = labels[labels.size() - 1];
images.pop_back();
labels.pop_back();
  Ptr<BasicFaceRecognizer>model = createFisherFaceRecognizer();
  model->train(images, labels);
  Mat mean = model->getMean();
  if(argc == 2) {
  imshow("mean", norm_0_255(mean.reshape(1,height)));
  } else {
    imwrite(format("%s/mean.jpeg", output_folder.c_str()), norm_0_255(mean.reshape(1,height)));
  }
  if(argc==2)
   {
    waitKey(0);
  }

 return 0;

 }