17,23 → 17,23 |
#include <sys/time.h> |
#include <math.h> |
|
#define SOUND_SPEED 340.0 // sound speed in air in metrs per second |
#define MAX_RANGE 10.0 // maximal working radius in meters |
|
static char *device = "plughw:0,0"; /* playback device */ |
static snd_pcm_format_t format = SND_PCM_FORMAT_S16; /* sample format */ |
static unsigned int rate = 98000; /* stream rate */ |
static unsigned int buffer_time = 500000; /* ring buffer length in us */ |
static unsigned int period_time = 100000; /* period time in us */ |
static unsigned int rate = 96000; /* stream rate */ |
static unsigned int buffer_time = MAX_RANGE / SOUND_SPEED * 1e6; /* ring buffer length in us */ |
static unsigned int period_time = MAX_RANGE / SOUND_SPEED * 1e5; /* period time in us */ |
static int resample = 1; /* enable alsa-lib resampling */ |
static int period_event = 0; /* produce poll event after each period */ |
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#define SOUND_SPEED 340 |
#define SIGNAL_SAMPLES 100000 |
#define CHIRP_OFFSET 0 |
|
unsigned int chirp_size; |
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int period=0; |
int cperiod=0; |
int chirp[100000]; |
short *chirp; |
short signal[1000000]; // record 6s of input samples |
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static snd_pcm_sframes_t buffer_size; // size of buffer at sound card |
48,31 → 48,36 |
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/* choose all parameters */ |
err = snd_pcm_hw_params_any(handle, params); |
if (err < 0) { |
if (err < 0) |
{ |
printf("Broken configuration for playback: no configurations available: %s\n", snd_strerror(err)); |
return err; |
} |
/* set hardware resampling */ |
err = snd_pcm_hw_params_set_rate_resample(handle, params, resample); |
if (err < 0) { |
if (err < 0) |
{ |
printf("Resampling setup failed for playback: %s\n", snd_strerror(err)); |
return err; |
} |
/* set the interleaved read/write format */ |
err = snd_pcm_hw_params_set_access(handle, params, SND_PCM_ACCESS_RW_INTERLEAVED); |
if (err < 0) { |
if (err < 0) |
{ |
printf("Access type not available for playback: %s\n", snd_strerror(err)); |
return err; |
} |
/* set the sample format */ |
err = snd_pcm_hw_params_set_format(handle, params, format); |
if (err < 0) { |
if (err < 0) |
{ |
printf("Sample format not available for playback: %s\n", snd_strerror(err)); |
return err; |
} |
/* set the count of channels */ |
err = snd_pcm_hw_params_set_channels(handle, params, channels); |
if (err < 0) { |
if (err < 0) |
{ |
printf("Channels count (%i) not available for playbacks: %s\n", channels, snd_strerror(err)); |
return err; |
} |
79,11 → 84,13 |
/* set the stream rate */ |
rrate = rate; |
err = snd_pcm_hw_params_set_rate_near(handle, params, &rrate, 0); |
if (err < 0) { |
if (err < 0) |
{ |
printf("Rate %iHz not available for playback: %s\n", rate, snd_strerror(err)); |
return err; |
} |
if (rrate != rate) { |
if (rrate != rate) |
{ |
printf("Rate doesn't match (requested %iHz, get %iHz)\n", rate, err); |
return -EINVAL; |
} |
90,31 → 97,42 |
else printf("Rate set to %i Hz\n", rate, err); |
/* set the buffer time */ |
err = snd_pcm_hw_params_set_buffer_time_near(handle, params, &buffer_time, &dir); |
if (err < 0) { |
if (err < 0) |
{ |
printf("Unable to set buffer time %i for playback: %s\n", buffer_time, snd_strerror(err)); |
return err; |
} |
err = snd_pcm_hw_params_get_buffer_size(params, &size); |
if (err < 0) { |
if (err < 0) |
{ |
printf("Unable to get buffer size for playback: %s\n", snd_strerror(err)); |
return err; |
} |
buffer_size = size; |
/* set the period time */ |
printf("Bufffer size set to: %d Requested buffer time: %ld \n", (int) buffer_size, (long) buffer_time); |
|
|
/// set the period time |
err = snd_pcm_hw_params_set_period_time_near(handle, params, &period_time, &dir); |
if (err < 0) { |
if (err < 0) |
{ |
printf("Unable to set period time %i for playback: %s\n", period_time, snd_strerror(err)); |
return err; |
} |
|
err = snd_pcm_hw_params_get_period_size(params, &size, &dir); |
if (err < 0) { |
if (err < 0) |
{ |
printf("Unable to get period size for playback: %s\n", snd_strerror(err)); |
return err; |
} |
period_size = size; |
printf("Period size set to: %d Requested period time: %ld \n", (int) period_size, (long) period_time); |
|
/* write the parameters to device */ |
err = snd_pcm_hw_params(handle, params); |
if (err < 0) { |
if (err < 0) |
{ |
printf("Unable to set hw params for playback: %s\n", snd_strerror(err)); |
return err; |
} |
127,35 → 145,30 |
|
/* get the current swparams */ |
err = snd_pcm_sw_params_current(handle, swparams); |
if (err < 0) { |
if (err < 0) |
{ |
printf("Unable to determine current swparams for playback: %s\n", snd_strerror(err)); |
return err; |
} |
/* start the transfer when the buffer is almost full: */ |
/* (buffer_size / avail_min) * avail_min */ |
err = snd_pcm_sw_params_set_start_threshold(handle, swparams, (buffer_size / period_size) * period_size); |
if (err < 0) { |
// start the transfer when the buffer is almost full: never fou our case |
err = snd_pcm_sw_params_set_start_threshold(handle, swparams, 2 * buffer_size); |
if (err < 0) |
{ |
printf("Unable to set start threshold mode for playback: %s\n", snd_strerror(err)); |
return err; |
} |
/* allow the transfer when at least period_size samples can be processed */ |
/* or disable this mechanism when period event is enabled (aka interrupt like style processing) */ |
err = snd_pcm_sw_params_set_avail_min(handle, swparams, period_event ? buffer_size : period_size); |
if (err < 0) { |
printf("Unable to set avail min for playback: %s\n", snd_strerror(err)); |
return err; |
} |
/* enable period events when requested */ |
if (period_event) { |
|
err = snd_pcm_sw_params_set_period_event(handle, swparams, 1); |
if (err < 0) { |
if (err < 0) |
{ |
printf("Unable to set period event: %s\n", snd_strerror(err)); |
return err; |
} |
} |
|
/* write the parameters to the playback device */ |
err = snd_pcm_sw_params(handle, swparams); |
if (err < 0) { |
if (err < 0) |
{ |
printf("Unable to set sw params for playback: %s\n", snd_strerror(err)); |
return err; |
} |
162,7 → 175,8 |
return 0; |
} |
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struct async_private_data { |
struct async_private_data |
{ |
signed short *samples; |
snd_pcm_channel_area_t *areas; |
unsigned int period; |
170,22 → 184,7 |
|
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////// SIGNAL GENERATION STUFF |
/*int linear_chirp(int *pole, int delka_pole){ // vygeneruje linearni chirp a vzorky ulozi do pole |
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static const float f0 = 0.0001; |
static const float k = 0.00001; |
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int t; |
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// if((spozdeni+delka) < delka_pole) |
for(t=0;t < delka_pole;t++) pole[t] = round ( 10000*sin(2*M_PI*(t+faze)*(f0+(k/2)*(t+faze))) ); |
faze +=t; |
// else return 0; |
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}*/ |
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// vygeneruje linearni chirp a vzorky ulozi do pole |
unsigned int linear_windowed_chirp(unsigned int *pole, unsigned int delka_pole,unsigned int offset) |
unsigned int linear_windowed_chirp(short *pole) |
{ |
unsigned int maxval = (1 << (snd_pcm_format_width(format) - 1)) - 1; |
|
196,43 → 195,19 |
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unsigned int n=0; |
double t; |
unsigned int perioda; |
unsigned int chirp_samples; // number of samples per period |
|
k=2*(fmax-f0)/Tw; |
perioda = rate*Tw; |
chirp_samples = ceil(rate*Tw); |
|
for(n=0;n<=perioda;n++){ |
for (n=0;n<=chirp_samples;n++) |
{ |
t = (double) n/ (double)rate; |
pole[n+offset] = (short) floor( (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))) ); |
pole[n] = (short) floor( (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+offset); |
return (chirp_samples); |
} |
|
// generate sine samples and store |
int sine(unsigned int *pole, unsigned int delka_pole) |
{ |
unsigned int maxval = (1 << (snd_pcm_format_width(format) - 1)) - 1; |
unsigned int n; |
double t; |
|
for(n=0;n < delka_pole;n++){ |
t = 440.0 * (double) n/ (double)rate; |
pole[n] = (short) floor(maxval*sin(2*M_PI*t)); |
} |
} |
//// generate simple sine ping |
unsigned int sine_ping(unsigned int *pole, unsigned int delka_pole,unsigned int offset, double frequency) |
{ |
unsigned int maxval = (1 << (snd_pcm_format_width(format) - 1)) - 1; |
unsigned int n; |
double t; |
|
for(n=0;n < delka_pole;n++){ |
t = frequency * (double) n/ (double)rate; |
pole[n] = (short) floor(maxval*sin(2*M_PI*t)); |
} |
} |
|
/////////// CALL BACK STUFF /////////////////// |
static void async_playback_callback(snd_async_handler_t *ahandler) |
{ |
241,14 → 216,17 |
int err; |
|
avail = snd_pcm_avail_update(handle); |
while ((avail >= period_size) && ((period*period_size) < chirp_size) ) { |
while ((avail >= period_size) && ((period*period_size) < chirp_size) ) |
{ |
|
err = snd_pcm_writei(handle, (chirp+period*period_size), period_size); |
if (err < 0) { |
if (err < 0) |
{ |
printf("Write error: %s\n", snd_strerror(err)); |
exit(EXIT_FAILURE); |
} |
if (err != period_size) { |
if (err != period_size) |
{ |
printf("Write error: written %i expected %li\n", err, period_size); |
exit(EXIT_FAILURE); |
} |
264,14 → 242,17 |
int err; |
|
avail = snd_pcm_avail_update(handle); |
while ((avail >= period_size) /*&& ((period*period_size) < (CHIRP_SIZE-100))*/ ) { // segmentation fault checking disabled |
while ((avail >= period_size) /*&& ((period*period_size) < (CHIRP_SIZE-100))*/ ) // segmentation fault checking disabled |
{ |
|
err = snd_pcm_readi(handle, (signal+cperiod*period_size), period_size); |
if (err < 0) { |
if (err < 0) |
{ |
printf("Read error: %s\n", snd_strerror(err)); |
exit(EXIT_FAILURE); |
} |
if (err != period_size) { |
if (err != period_size) |
{ |
printf("Read error: red %i expected %li\n", err, period_size); |
exit(EXIT_FAILURE); |
} |
310,111 → 291,122 |
printf("Simple PC sonar ver. 000000001 starting work.. \n"); |
|
//open and set playback device |
if ((err = snd_pcm_open(&playback_handle, device, SND_PCM_STREAM_PLAYBACK, 0)) < 0) { |
if ((err = snd_pcm_open(&playback_handle, device, SND_PCM_STREAM_PLAYBACK, 0)) < 0) |
{ |
printf("Playback open error: %s\n", snd_strerror(err)); |
return 0; |
} |
|
if ((err = set_hwparams(playback_handle, hwparams, 1)) < 0) { |
if ((err = set_hwparams(playback_handle, hwparams, 1)) < 0) |
{ |
printf("Setting of hwparams failed: %s\n", snd_strerror(err)); |
exit(EXIT_FAILURE); |
} |
if ((err = set_swparams(playback_handle, swparams)) < 0) { |
if ((err = set_swparams(playback_handle, swparams)) < 0) |
{ |
printf("Setting of swparams failed: %s\n", snd_strerror(err)); |
exit(EXIT_FAILURE); |
} |
|
//open and set capture device |
if ((err = snd_pcm_open(&capture_handle, device, SND_PCM_STREAM_CAPTURE, 0)) < 0) { |
if ((err = snd_pcm_open(&capture_handle, device, SND_PCM_STREAM_CAPTURE, 0)) < 0) |
{ |
printf("Playback open error: %s\n", snd_strerror(err)); |
return 0; |
} |
|
if ((err = set_hwparams(capture_handle, hwparams, 2)) < 0) { |
if ((err = set_hwparams(capture_handle, hwparams, 2)) < 0) |
{ |
printf("Setting of hwparams failed: %s\n", snd_strerror(err)); |
exit(EXIT_FAILURE); |
} |
if ((err = set_swparams(capture_handle, swparams)) < 0) { |
if ((err = set_swparams(capture_handle, swparams)) < 0) |
{ |
printf("Setting of swparams failed: %s\n", snd_strerror(err)); |
exit(EXIT_FAILURE); |
} |
|
// generate ping pattern |
chirp = malloc(2*period_size * sizeof(short)); |
chirp_size = linear_windowed_chirp(chirp); |
|
chirp_size=linear_windowed_chirp(chirp,1000000, CHIRP_OFFSET); |
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// register playback callback |
err = snd_async_add_pcm_handler(&phandler, playback_handle, async_playback_callback, &data); // fill by dummy &data |
if (err < 0) { |
/* err = snd_async_add_pcm_handler(&phandler, playback_handle, async_playback_callback, &data); // fill by dummy &data |
if (err < 0) |
{ |
printf("Unable to register async handler\n"); |
exit(EXIT_FAILURE); |
} |
}*/ |
|
if ((err = snd_pcm_prepare (playback_handle)) < 0) { |
fprintf (stderr, "cannot prepare audio interface for use (%s)\n", |
snd_strerror (err)); |
exit (1); |
} |
// for (period = 0; period < 2; period++) |
|
/* for (period = 0; period < 2; period++) { |
|
err = snd_pcm_writei(playback_handle, (chirp+period*period_size), period_size); |
if (err < 0) { |
err = snd_pcm_writei(playback_handle, chirp, period_size); |
if (err < 0) |
{ |
printf("Initial write error: %s\n", snd_strerror(err)); |
exit(EXIT_FAILURE); |
} |
if (err != period_size) { |
/* if (err != period_size) |
{ |
printf("Initial write error: written %i expected %li\n", err, period_size); |
exit(EXIT_FAILURE); |
} |
}*/ |
|
// register capture callback |
err = snd_async_add_pcm_handler(&chandler, capture_handle, async_capture_callback, &data); // fill by dummy &data |
if (err < 0) { |
/* err = snd_async_add_pcm_handler(&chandler, capture_handle, async_capture_callback, &data); // fill by dummy &data |
if (err < 0) |
{ |
printf("Unable to register async handler\n"); |
exit(EXIT_FAILURE); |
} |
}*/ |
|
snd_pcm_link(capture_handle,playback_handle); //link capture and playback together |
|
//start sream |
if ((err = snd_pcm_prepare (capture_handle)) < 0) { |
/* if ((err = snd_pcm_prepare (capture_handle)) < 0) |
{ |
fprintf (stderr, "cannot prepare audio interface for use (%s)\n", |
snd_strerror (err)); |
exit (1); |
} |
else printf("Capture device prepared...\n");*/ |
|
err = snd_pcm_start(capture_handle); |
if (err < 0) { |
err = snd_pcm_start(playback_handle); |
if (err < 0) |
{ |
printf("Start error: %s\n", snd_strerror(err)); |
exit(EXIT_FAILURE); |
} |
else printf("Waiting for transmitt all samples\n"); |
|
//wait until all samples aren't transmitted |
printf("Waiting for transmitt all samples\n"); |
while(cperiod<10) { |
sleep(1); |
while ( snd_pcm_avail(capture_handle) < period_size ) |
{ |
usleep(1000); |
printf("."); |
} |
|
//// stop audio?? |
err = snd_pcm_drop(capture_handle); |
if (err < 0) |
{ |
printf("Stop error: %s\n", snd_strerror(err)); |
exit(EXIT_FAILURE); |
} |
|
|
j=0; |
for(i=0;i < SIGNAL_SAMPLES;i++){ |
for (i=0;i < SIGNAL_SAMPLES;i++) |
{ |
L_signal[i]=signal[j]; |
R_signal[i]=signal[j+1]; |
j+=2; |
} |
|
// linear_windowed_chirp(L_signal,1000000, 1000); |
|
printf("\nData transmitted... \ncorrelating...\n"); |
for(n=0; n < (SIGNAL_SAMPLES - chirp_size);n++){ |
printf("Data transmitted... \ncorrelating...\n"); |
for (n=0; n < (SIGNAL_SAMPLES - chirp_size);n++) |
{ |
l=0; |
r=0; |
for(m=CHIRP_OFFSET;m < chirp_size;m++) |
for (m=0;m < chirp_size;m++) |
{ |
l += chirp[m]*L_signal[m+n]; // correlate with left channel |
r += chirp[m]*R_signal[m+n]; // correlate with right channel |
423,23 → 415,28 |
correlationr[n]=r; |
} |
|
printf("\nSearching echos...\n"); |
printf("Searching echos...\n"); |
r=0; |
l=0; |
for(n=0; n < (SIGNAL_SAMPLES - chirp_size);n++){ //najde nejvetsi korelace |
if (l < correlationl[n]){ |
for (n=0; n < (SIGNAL_SAMPLES - chirp_size);n++) //najde nejvetsi korelace |
{ |
if (l < correlationl[n]) |
{ |
delay[1] = n; |
l = correlationl[n]; |
} |
if (r < correlationr[n]){ |
if (r < correlationr[n]) |
{ |
delay[2] = n; |
r = correlationr[n]; |
} |
} |
|
printf("\nWriting output file...\n"); |
out=fopen("/tmp/sonar.txt","w"); |
j=0; |
for(i=0;i<=100000;i++){ |
for (i=0;i<=period_size;i++) |
{ |
fprintf(out,"%6d %6d %6d %6d %9ld %9ld\n",i,chirp[i],L_signal[i],R_signal[i],correlationl[i], correlationr[i]); |
j+=2; |
} |