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simple-tone: generate S16 format samples

This commit is contained in:
Kamal Mostafa 2012-08-11 21:19:30 -07:00
parent 3053ea78bc
commit 5dddc1445a
1 changed files with 26 additions and 4 deletions
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30
src/simple-tone-generator.c
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@ -40,16 +40,38 @@ simpleaudio_tone(simpleaudio *sa_out, float tone_freq, size_t nsamples_dur)
{
unsigned int framesize = simpleaudio_get_framesize(sa_out);
float *buf = malloc(nsamples_dur * framesize);
void *buf = malloc(nsamples_dur * framesize);
assert(buf);
if ( tone_freq != 0 ) {
float wave_nsamples = simpleaudio_get_rate(sa_out) / tone_freq;
size_t i;
for ( i=0; i<nsamples_dur; i++ )
buf[i] = sinf( M_PI*2.0*( i/wave_nsamples + sa_tone_cphase) );
#define SINE_PHASE_ANGLE ( M_PI*2.0*(i/wave_nsamples + sa_tone_cphase) )
switch ( simpleaudio_get_format(sa_out) ) {
case SA_SAMPLE_FORMAT_FLOAT:
{
float *float_buf = buf;
for ( i=0; i<nsamples_dur; i++ )
float_buf[i] = sinf(SINE_PHASE_ANGLE);
}
break;
case SA_SAMPLE_FORMAT_S16:
{
short *float_buf = buf;
for ( i=0; i<nsamples_dur; i++ )
float_buf[i] = 32767 * sinf(SINE_PHASE_ANGLE);
}
break;
default:
assert(0);
break;
}
sa_tone_cphase
= fmodf(sa_tone_cphase + (float)nsamples_dur/wave_nsamples, 1.0);