void insert_rest(short waveform[], int notelength, FILE *f) {
int i ;
for ( i = 0 ; i < notelength ; i++) {
waveform[i] = 0 ;
}
wavfile_write(f, waveform, notelength) ;
}
void create_note(int volume, int length, double frequency, short waveform[NUM_SAMPLES], FILE *f)
{
int i;
for(i=0;i<length;i++)
{
double t = (double) i / WAVFILE_SAMPLES_PER_SECOND;
waveform[i] = volume*sin(frequency*t*2*M_PI);
}
wavfile_write(f,waveform,length);
}
void update_waveform(short waveform[], int maxvolume, double frequency, int notelength, FILE *f) {
int i ;
int volume ;
float t ;
for ( i = 0 ; i < notelength ; i++) {
t = (float) i / WAVFILE_SAMPLES_PER_SECOND ;
volume = maxvolume ;
//volume = adjust_volume(maxvolume, t, notelength) ; //not used in the final program because it will not produce sound
waveform[i] = triangle_waveform(frequency, .4*volume, t) + triangle_waveform(2*frequency, .2*volume, t) + triangle_waveform(4*frequency, .6*volume, t) ;
}
wavfile_write(f, waveform, notelength) ;
}
int main()
{
short waveform[NUM_SAMPLES];
double frequency = 440.0;
int volume = 32000;
FILE * f;
int length = NUM_SAMPLES;
int i;
f = wavfile_open("sound.wav");
if(!f) {
printf("couldn't open sound.wav for writing: %s",strerror(errno));
return 1;
}
for(i=0;i<length;i = i+4) {
double t = (double) i / WAVFILE_SAMPLES_PER_SECOND;
waveform[i] = volume*sin(frequency*t*2*M_PI);
}
for(i=1;i<length;i = i + 4) {
double t = (double) i / WAVFILE_SAMPLES_PER_SECOND;
waveform[i] = (volume*(.3333))*sin(frequency*(.3333)*t*2*M_PI);
}
for(i=2;i<length;i = i + 4) {
double t = (double) i / WAVFILE_SAMPLES_PER_SECOND;
waveform[i] = (volume*(.5))*sin(frequency*(.5)*t*2*M_PI);
}
for(i=3;i<length;i = i+4) {
double t = (double) i / WAVFILE_SAMPLES_PER_SECOND;
waveform[i] = volume*.25*sin(frequency*.25*t*2*M_PI);
}
wavfile_write(f,waveform,length);
wavfile_close(f);
return 0;
}
