//Our callback function with all stream data
void TutorialApplication :: visualize(int chan,int* stream,int len) {
	 fftw_complex *in, *out;
	 fftw_plan p;
	 int N = 512;

	 if(len<N) {
		 return;
	 }

	 int cut = len / 512;

	 SDL_LockMutex(m_mtx);
	 in = (fftw_complex*) fftw_malloc(sizeof(fftw_complex) * N);

	 long long int y;
	 for(int i=0;i<N;i+=cut) {
		 if( (cut%2 == 0) || (i==0) ) {
			 y = stream[i] * stream[i+1];
			 in[i][0] = y * (1.0/65536) ;
			 in[i][1] = 0;
		 }
		 else {
			y = stream[i-1] * stream[i];
			in[i][0] = y *  (1.0/65536);
			in[i][1] = 0;
		 }
	 }
	 SDL_UnlockMutex(m_mtx);

	 out = (fftw_complex*) fftw_malloc(sizeof(fftw_complex) * N);
	 p = fftw_plan_dft_1d(N, in, out, FFTW_FORWARD, FFTW_ESTIMATE);
	 fftw_execute(p);

	SDL_LockMutex(m_mtx);
	std::cout << "\n\n";
	std::cout << len << " " << cut <<"\n";
	long long int temp;
	long double result;
	for(int i=0;i<N;i++) {
		temp = out[i][0]*out[i][0] + out[i][1]*out[i][1];
		result = sqrt(temp)*(1.0/65536);
		//std::cout << out[i][0] <<"+"<<out[i][1] << "*i ;";
		std::cout << i << ":" <<  result  << "\n";
	}

	std::cout << "\n" << "\n";
	SDL_UnlockMutex(m_mtx);

	fftw_destroy_plan(p);
	fftw_free(in);
	fftw_free(out);

}