C++ - Play back a tone generated from a sinusoidal wave

Question

Hey everyone, I\'m currently trying to figure out how to play back a tone I have generated using a sinusoidal wave.

Here\'s my code:

#include 

        

Answer 1

Try this (this program uses Z transform concept, a complete example that generates dtmf tones using ALSA and compilable on LINUX are available here)‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌‌:

/*
 *  Cosine Samples Generator
 *
 *  Autor: Volnei Klehm
 *  Data: 04/01/2014
 */

#include 
#include 

#define S_FREQ 8000 /*Sample frequency, should be greater thar 2*sineFrequency
          If using audio output it has to be the same saple frequency 
          Used there*/

const float frequency_in_Hertz = 697; /*set output frequency*/
const float generatorContant1 = cosf(2*M_PI*(frequency_in_Hertz/S_FREQ));
const float generatorContant2 = sinf(2*M_PI*(frequency_in_Hertz/S_FREQ));


float GenerateSignal(){
  static float Register[2]={1,0};
  static float FeedBack;

  FeedBack=2*generatorContant1*Register[0]-Register[1];
  Register[1]=Register[0];  
  Register[0]=FeedBack;

  return (generatorContant2*Register[1]);
}


int main(void) {
  /*generate 300 samples*/
  for (int NumberOfSamples = 300; NumberOfSamples > 0; NumberOfSamples--) 
    printf("\n%f", GenerateSignal());
  return 0;
}