#include "opencv2/core/core.hpp"
	#include "opencv2/imgproc/imgproc.hpp"
	#include "opencv2/highgui/highgui.hpp"

	#include <iostream>

	using namespace cv;
	using namespace std;

	void help(char* progName)
	{
		cout << endl
			<<  "This program demonstrated the use of the discrete Fourier transform (DFT). " << endl
			<<  "The dft of an image is taken and it's power spectrum is displayed."          << endl
			<<  "Usage:"                                                                      << endl
			<< progName << " [image_name -- default lena.jpg] "                       << endl << endl;
	}

	int main(int argc, char ** argv)
	{
		help(argv[0]);
		const char* filename = argc >=2 ? argv[1] : "./lena.jpg";

		Mat I = imread(filename, CV_LOAD_IMAGE_GRAYSCALE);
		if( I.empty())
		{
			cout<<endl<<"No file"<<endl;
			return -1;
		}
	}