23,11 → 23,11 |
static int resample = 1; /* enable alsa-lib resampling */ |
static int period_event = 0; /* produce poll event after each period */ |
|
#define CHIRP_SIZE 1000000 |
unsigned int chirp_size; |
|
int period=0; |
int cperiod=0; |
short chirp[CHIRP_SIZE]; |
int chirp[1000000]; |
short signal[44100*6]; // record 6s of input samples |
|
static snd_pcm_sframes_t buffer_size; // size of buffer at sound card |
228,34 → 228,39 |
|
|
|
int linear_windowed_chirp(int *pole, int delka_pole){ // vygeneruje linearni chirp a vzorky ulozi do pole |
unsigned int linear_windowed_chirp(unsigned int *pole, unsigned int delka_pole){ // vygeneruje linearni chirp a vzorky ulozi do pole |
|
unsigned int maxval = (1 << (snd_pcm_format_width(format) - 1)) - 1; |
|
static const float f0 = 1/1000; |
static const float fmax = 1/10000; |
static const float Tw = 10; |
|
static const float f0 = 1000; |
static const float fmax = 5000; |
static const float Tw = 0.2; |
static float k; |
|
unsigned int n=0; |
double t; |
unsigned int perioda; |
|
//k=2*(fmax-Tw*f0)/Tw*Tw; |
k=1/10000; |
k=2*(fmax-f0)/Tw; |
perioda = rate*Tw; |
|
int n; |
double t; |
|
for(n=0;n < delka_pole;n++){ |
t=n*1/rate; |
pole[n] = (short) round ( /*(0.35875 - 0.48829*cos((t)*0.0001) + 0.14128*cos(.0002*(t)) - 0.01168*cos(.0003*(t)))*/ maxval*sin(2*M_PI*(t)*(f0+(k/2)*(t))) ); |
for(n=0;n<=perioda;n++){ |
t = (double) n/ (double)rate; |
pole[n] = (short) round ( (0.35875 - 0.48829*cos(2*M_PI*t*1/Tw) + 0.14128*cos(2*M_PI*2*t*1/Tw) - 0.01168*cos(2*M_PI*3*t*1/Tw))*maxval*sin(2*M_PI*(t)*(f0+(k/2)*(t))) ); |
} |
return perioda; |
} |
|
int sine(int *pole, int delka_pole) |
int sine(unsigned int *pole, unsigned int delka_pole) |
{ |
unsigned int maxval = (1 << (snd_pcm_format_width(format) - 1)) - 1; |
int t; |
for(t=0;t < delka_pole;t++) pole[t] = (short) round(maxval*sin( (double)(t)/10.0)); |
unsigned int n; |
double t; |
|
for(n=0;n < delka_pole;n++){ |
t = 440.0 * (double) n/ (double)rate; |
pole[n] = (short) round(maxval*sin(2*M_PI*t)); |
} |
} |
|
|
270,7 → 275,7 |
int err; |
|
avail = snd_pcm_avail_update(handle); |
while ((avail >= period_size) && ((period*period_size) < (CHIRP_SIZE-100)) ) { |
while ((avail >= period_size) && ((period*period_size) < chirp_size) ) { |
|
err = snd_pcm_writei(handle, (chirp+period*period_size), period_size); |
if (err < 0) { |
296,7 → 301,7 |
int err; |
|
avail = snd_pcm_avail_update(handle); |
// while ((avail >= period_size) /*&& ((period*period_size) < (CHIRP_SIZE-100))*/ ) { |
while ((avail >= period_size) /*&& ((period*period_size) < (CHIRP_SIZE-100))*/ ) { |
|
err = snd_pcm_readi(handle, (signal+cperiod*period_size), period_size); |
if (err < 0) { |
309,7 → 314,7 |
} |
avail = snd_pcm_avail_update(handle); |
cperiod++; |
// } |
} |
} |
|
|
364,36 → 369,8 |
exit(EXIT_FAILURE); |
} |
|
// allocate memory for frame (package of samples) |
frame = malloc((period_size * channels * snd_pcm_format_physical_width(format)) / 8); |
if (frame == NULL) { |
printf("No enough memory\n"); |
exit(EXIT_FAILURE); |
} |
chirp_size=linear_windowed_chirp(chirp,1000000); |
|
|
// dummy structure |
//allocate memory for frame structure definition |
areas = calloc(channels, sizeof(snd_pcm_channel_area_t)); |
if (areas == NULL) { |
printf("No enough memory\n"); |
exit(EXIT_FAILURE); |
} |
//fill areas by definition of frame structure |
for (chn = 0; chn < channels; chn++) { |
areas[chn].addr = frame; // frame start adress |
areas[chn].first = chn * snd_pcm_format_physical_width(format); // ofset to first sample (in bits) |
areas[chn].step = channels * snd_pcm_format_physical_width(format); // step between samples |
} |
|
data.samples = frame; |
data.areas = areas; |
data.period = 1; |
// end of dummy structure |
|
|
sine(chirp,100000); |
|
/// register playback callback |
err = snd_async_add_pcm_handler(&phandler, playback_handle, async_playback_callback, &data); // fill by dummy &data |
if (err < 0) { |
400,7 → 377,7 |
printf("Unable to register async handler\n"); |
exit(EXIT_FAILURE); |
} |
for (period = 0; period < 3; period++) { |
for (period = 0; period < 2; period++) { |
|
err = snd_pcm_writei(playback_handle, (chirp+period*period_size), period_size); |
if (err < 0) { |
446,17 → 423,14 |
|
/* because all other work is done in the signal handler, |
suspend the process */ |
while(cperiod<3) { |
while(cperiod<10) { |
sleep(1); |
} |
|
out=fopen("./output.txt","w"); |
for(i=0;i<=100000;i++) fprintf(out,"%d ",signal[i]); |
fclose(out); |
for(i=0;i<=100000;i++) fprintf(out,"%6d %6d \n",chirp[i],signal[i]); |
fclose(out); |
|
free(areas); |
free(frame); |
|
snd_pcm_close(playback_handle); |
snd_pcm_close(capture_handle); |
return 0; |