WebSVN – svnkaklik – Diff – /programy/C/ix86/echo/SW/sonar/src/sonar.c


///////////////////////////////////////////////////////////////////////////////////
//                        A small demo of sonar.
// Program allow distance measuring.
// Uses cross-correlation algorithm to find echos
//
// Author: kaklik  (kaklik@mlab.cz)
//$Id:$
///////////////////////////////////////////////////////////////////////////////////
 
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sched.h>
#include <errno.h>
#include <getopt.h>
#include <alsa/asoundlib.h>
#include <sys/time.h>
#include <math.h>
#include <fftw3.h>
 
#define SOUND_SPEED	340.0	// sound speed in air in metrs per second
#define MAX_RANGE	10.0	// maximal working radius in meters
#define APERTURE	0.2	// distance between microphones
 
 
 
 
static char *device = "plughw:0,0";			/* playback device */
static snd_pcm_format_t format = SND_PCM_FORMAT_S16;	/* sample format */
static unsigned int rate = 96000;			/* stream rate */
static unsigned int buffer_time = 2 * (MAX_RANGE / SOUND_SPEED * 1e6);		/* ring buffer length in us */
static unsigned int period_time = MAX_RANGE / SOUND_SPEED * 1e6;		/* period time in us */
static int resample = 1;				/* enable alsa-lib resampling */
 
unsigned int chirp_size;
 
static snd_pcm_sframes_t buffer_size;	// size of buffer at sound card
static snd_pcm_sframes_t period_size;	//samples per frame
static snd_output_t *output = NULL;
 
static int set_hwparams(snd_pcm_t *handle, snd_pcm_hw_params_t *params, unsigned int channels)
{
    unsigned int rrate;
    snd_pcm_uframes_t size;
    int err, dir;
 
    /* choose all parameters */
    err = snd_pcm_hw_params_any(handle, params);
    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)
    {
        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)
    {
        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)
    {
        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)
    {
        printf("Channels count (%i) not available for playbacks: %s\n", channels, snd_strerror(err));
        return err;
    }
    /* set the stream rate */
    rrate = rate;
    err = snd_pcm_hw_params_set_rate_near(handle, params, &rrate, 0);
    if (err < 0)
    {
        printf("Rate %iHz not available for playback: %s\n", rate, snd_strerror(err));
        return err;
    }
    if (rrate != rate)
    {
        printf("Rate doesn't match (requested %iHz, get %iHz)\n", rate, err);
        return -EINVAL;
    }
    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)
    {
        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)
    {
        printf("Unable to get buffer size for playback: %s\n", snd_strerror(err));
        return err;
    }
    buffer_size = size;
    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)
    {
        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)
    {
        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)
    {
        printf("Unable to set hw params for playback: %s\n", snd_strerror(err));
        return err;
    }
    return 0;
}
 
static int set_swparams(snd_pcm_t *handle, snd_pcm_sw_params_t *swparams)
{
    int err;
 
    /* get the current swparams */
    err = snd_pcm_sw_params_current(handle, swparams);
    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: 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;
    }
 
    err = snd_pcm_sw_params_set_period_event(handle, swparams, 1);
    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)
    {
        printf("Unable to set sw params for playback: %s\n", snd_strerror(err));
        return err;
    }
    return 0;
}
 
////// SIGNAL GENERATION STUFF
unsigned int linear_windowed_chirp(short *pole)
{
    unsigned int maxval = (1 << (snd_pcm_format_width(format) - 1)) - 1;
 
    static const float f0 = 5000;		//starting frequency
    static const float fmax = 10000;		//ending frequency
    static const float Tw = 0.0015;
    static float k;
 
    unsigned int n=0;
    double t;
    unsigned int chirp_samples;		// number of samples per period
 
    k=2*(fmax-f0)/Tw;
    chirp_samples = ceil(rate*Tw);
 
    for (n=0;n<=chirp_samples;n++)
    {
        t = (double) n / (double)rate;
        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 (chirp_samples);
}
 
int main(int argc, char *argv[])
{
    snd_pcm_t *playback_handle, *capture_handle;
    int err;
    snd_pcm_hw_params_t *hwparams;
    snd_pcm_sw_params_t *swparams;
 
    long int *correlationl, *correlationr;
    float *echo_map;
    int *L_signal, *R_signal;
    short *chirp, *signal;
    float *chirp_spect, *lecho_spect, *recho_spect;
    float x,y;
    unsigned int i,j,m,n;
    unsigned int delayl[10],delayr[10];	//store delay of signifed correlation
    long int l,r;  // store correlation at strict time
    double df;	//frequency resolution 
    unsigned int frequency_bins; // number of output frequency bins 
 
 
 
    double *inchirp;
    fftw_complex *outchirp;
    fftw_plan fft_plan_chirp;
 
    FILE *out;
 
    snd_pcm_hw_params_alloca(&hwparams);
    snd_pcm_sw_params_alloca(&swparams);
 
    printf("Simple PC sonar $Rev:$ starting work.. \n");
 
//open and set playback device
    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)
    {
        printf("Setting of hwparams failed: %s\n", snd_strerror(err));
        exit(EXIT_FAILURE);
    }
    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)
    {
        printf("Playback open error: %s\n", snd_strerror(err));
        return 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)
    {
        printf("Setting of swparams failed: %s\n", snd_strerror(err));
        exit(EXIT_FAILURE);
    }
 
    /*    err = snd_pcm_link( capture_handle, playback_handle); //link capture and playback together
        if (err < 0)
        {
            printf("Device linking error: %s\n", snd_strerror(err));
            exit(EXIT_FAILURE);
        }*/
 
    correlationl = malloc(period_size * sizeof(long int)); //array to store correlation curve
    correlationr = malloc(period_size * sizeof(long int)); //array to store correlation curve
    L_signal = malloc(period_size * sizeof(int));
    R_signal = malloc(period_size * sizeof(int));
    chirp = calloc(2*period_size, sizeof(short));
    signal = malloc(2*period_size * sizeof(short));
    echo_map = malloc(3*period_size * sizeof(float));   // Array to store two dimensional image of echos
 
// generate ping pattern
    chirp_size = linear_windowed_chirp(chirp);
 
    frequency_bins = chirp_size / 2 + 1;
    df = (double) rate / (double) chirp_size;
    chirp_spect = malloc(frequency_bins * sizeof(float));
    lecho_spect = malloc(frequency_bins * sizeof(float));
    recho_spect = malloc(frequency_bins * sizeof(float));
 
    inchirp = fftw_malloc(sizeof(double) * chirp_size); 		// allocate input array for FFT
    outchirp = fftw_malloc(sizeof(fftw_complex) * frequency_bins);
 
    fft_plan_chirp = fftw_plan_dft_r2c_1d(chirp_size, inchirp, outchirp, FFTW_ESTIMATE);
 
    printf("compute chirp spectrum\n");
    for(i=0; i < chirp_size; i++) inchirp[i] = chirp[i];
    fftw_execute(fft_plan_chirp);
    for(i=0; i < frequency_bins; i++) chirp_spect[i] = sqrt( outchirp[i][0] * outchirp[i][0] + outchirp[i][1] * outchirp[i][1] );
 
// write chirp data to souncard buffer
    err = snd_pcm_writei(playback_handle, chirp, period_size);
    if (err < 0)
    {
        printf("Initial write error: %s\n", snd_strerror(err));
        exit(EXIT_FAILURE);
    }
 
//start sream
    err = snd_pcm_start(playback_handle);
    if (err < 0)
    {
        printf("Start error: %s\n", snd_strerror(err));
        exit(EXIT_FAILURE);
    }
 
    err = snd_pcm_start(capture_handle);
    if (err < 0)
    {
        printf("Start error: %s\n", snd_strerror(err));
        exit(EXIT_FAILURE);
    }
    else printf("Transmitting all samples of chirp\n");
//--------------
 
    while ( snd_pcm_avail_update(capture_handle) < period_size)			// wait for one period of data
    {
        usleep(1000);
        printf(".");
    }
 
    err = snd_pcm_drop(playback_handle);		// stop audio stream
    err = snd_pcm_drain(capture_handle);
    if (err < 0)
    {
        printf("Stop error: %s\n", snd_strerror(err));
        exit(EXIT_FAILURE);
    }
 
    err = snd_pcm_readi(capture_handle, signal, period_size);		//read period from audio buffer
    if (err < 0)
    {
        printf("Read error: %s\n", snd_strerror(err));
        exit(EXIT_FAILURE);
    }
 
    j=0;
    for (i=0;i < period_size;i++)		// separe inretleaved samples to two arrays
    {
        L_signal[i]=signal[j];
        R_signal[i]=signal[j+1];
        j+=2;
    }
 
    printf("\nData transmitted \ncorrelating\n");
    for (n=0; n < (period_size - chirp_size - 1); n++)
    {
        l=0;
        r=0;
        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
        }
        correlationl[n]=abs(l);
        correlationr[n]=abs(r);
    }
 
    m=0;
    printf("Building echo map\n");		// compute map from left and right correlation data
 
 
 
	for (i=0;i < period_size; i++)
	{
		for(j=0;j < period_size; j++)
		{
			echo_map[m]=(i*i-j*j+APERTURE*APERTURE)/(2*APERTURE);
			echo_map[m+1]=sqrt(-(i-j-APERTURE)*(i+j-APERTURE)*(i-j+APERTURE)*(i+j+APERTURE))/(2*r);
			echo_map[m+2]=correlationl[i]*correlationr[j];
			m+=3;
		}
	}
 
 
 
    printf("Searching echos\n");
    r=0;
    l=0;
    for (n=0; n < period_size;n++) 			//najde nejvetsi korelace
    {
        if (l < correlationl[n])
        {
            delayl[1] = n;
            l = correlationl[n];
        }
        if (r < correlationr[n])
        {
            delayr[1] = n;
            r = correlationr[n];
        }
    }
 
//spocitej frekvencni spektrum pro levy kanal
    for(i=delayl[1]; i < delayl[1] + chirp_size; i++) inchirp[i-delayl[1]] = L_signal[i];
    fftw_execute(fft_plan_chirp);
    for(i=0; i < frequency_bins; i++) lecho_spect[i] = sqrt(outchirp[i][0] * outchirp[i][0] + outchirp[i][1] * outchirp[i][1]);
 
 
// napln pole daty z praveho kanalu a spocitej frekvencni spektrum
    for(i=delayr[1]; i < delayr[1] + chirp_size; i++) inchirp[i-delayr[1]] = R_signal[i];
    fftw_execute(fft_plan_chirp);
    for(i=0; i < frequency_bins; i++) recho_spect[i] = sqrt(outchirp[i][0] * outchirp[i][0] + outchirp[i][1] * outchirp[i][1]);
 
    printf("Writing output files\n");
    out=fopen("/tmp/sonar.txt","w");
    for (i=0; i <= (period_size - 1); i++)
    {
        fprintf(out,"%2.3f %6d %6d %9ld %9ld\n",SOUND_SPEED * (float) i / rate,L_signal[i],R_signal[i],correlationl[i], correlationr[i]);
    }
    fclose(out);
 
    j=0;
    out=fopen("/tmp/plane_cut.txt","w"); // writes plane cut - e.g. density map to file
    for (i=0;i < period_size; i++)
    {
	fprintf(out,"%3.2f %3.2f %3.2f\n", echo_map[j], echo_map[j+1], echo_map[j+2]);
	j+=3;
    }
 
    out=fopen("/tmp/chirp.txt","w");
    for (i=0; i <= (chirp_size - 1); i++)
    {
        fprintf(out,"%6d %6d\n", i, chirp[i]);
    }
    fclose(out);
 
    out=fopen("/tmp/echo.txt","w");
    for(i=0; i < chirp_size; i++) fprintf(out,"%6d %6d %6d\n", i, L_signal[i + delayl[1]], R_signal[i + delayr[1]]);
    fclose(out);
 
    out=fopen("/tmp/spektra.txt","w");
    for (i=0; i < frequency_bins; i++)
    {
        fprintf(out,"%4.3f %4.3f %4.3f %4.3f\n", (i+0.5) * df, chirp_spect[i], lecho_spect[i], recho_spect[i]);
    }
    fclose(out);
 
    free(correlationl);
    free(correlationr);
    free(L_signal);
    free(R_signal);
    free(chirp);
    free(signal);
    free(echo_map);
 
    snd_pcm_close(playback_handle);
    snd_pcm_close(capture_handle);
    return 0;
}
 

Rev 645	Rev 646
1	`///////////////////////////////////////////////////////////////////////////////////`	1	`///////////////////////////////////////////////////////////////////////////////////`
2	`// A small demo of sonar.`	2	`// A small demo of sonar.`
3	`// Program allow distance measuring.`	3	`// Program allow distance measuring.`
4	`// Uses cross-correlation algorithm to find echos`	4	`// Uses cross-correlation algorithm to find echos`
5	`//`	5	`//`
6	`// Author: kaklik (kaklik@mlab.cz)`	6	`// Author: kaklik (kaklik@mlab.cz)`
7	`//`	7	`//$Id:$`
8	`///////////////////////////////////////////////////////////////////////////////////`	8	`///////////////////////////////////////////////////////////////////////////////////`
9		9
10	`#include <stdio.h>`	10	`#include <stdio.h>`
11	`#include <stdlib.h>`	11	`#include <stdlib.h>`
12	`#include <string.h>`	12	`#include <string.h>`
13	`#include <sched.h>`	13	`#include <sched.h>`
14	`#include <errno.h>`	14	`#include <errno.h>`
15	`#include <getopt.h>`	15	`#include <getopt.h>`
16	`#include <alsa/asoundlib.h>`	16	`#include <alsa/asoundlib.h>`
17	`#include <sys/time.h>`	17	`#include <sys/time.h>`
18	`#include <math.h>`	18	`#include <math.h>`
19	`#include <fftw3.h>`	19	`#include <fftw3.h>`
20		20
21	`#define SOUND_SPEED 340.0 // sound speed in air in metrs per second`	21	`#define SOUND_SPEED 340.0 // sound speed in air in metrs per second`
22	`#define MAX_RANGE 10.0 // maximal working radius in meters`	22	`#define MAX_RANGE 10.0 // maximal working radius in meters`
23	`#define APERTURE 0.2 // distance between microphones`	23	`#define APERTURE 0.2 // distance between microphones`
24	`#define MAP_SIZE 100`	-
25		-
26	`#define RESOLUTION 100 // resolution per map pixel`	-
27		24
28	`static char device = "plughw:0,0"; / playback device */`	25	`static char device = "plughw:0,0"; / playback device */`
29	`static snd_pcm_format_t format = SND_PCM_FORMAT_S16; /* sample format */`	26	`static snd_pcm_format_t format = SND_PCM_FORMAT_S16; /* sample format */`
30	`static unsigned int rate = 96000; /* stream rate */`	27	`static unsigned int rate = 96000; /* stream rate */`
31	`static unsigned int buffer_time = 2 * (MAX_RANGE / SOUND_SPEED * 1e6); /* ring buffer length in us */`	28	`static unsigned int buffer_time = 2 * (MAX_RANGE / SOUND_SPEED * 1e6); /* ring buffer length in us */`
32	`static unsigned int period_time = MAX_RANGE / SOUND_SPEED * 1e6; /* period time in us */`	29	`static unsigned int period_time = MAX_RANGE / SOUND_SPEED * 1e6; /* period time in us */`
33	`static int resample = 1; /* enable alsa-lib resampling */`	30	`static int resample = 1; /* enable alsa-lib resampling */`
34		31
35	`unsigned int chirp_size;`	32	`unsigned int chirp_size;`
36		33
37	`static snd_pcm_sframes_t buffer_size; // size of buffer at sound card`	34	`static snd_pcm_sframes_t buffer_size; // size of buffer at sound card`
38	`static snd_pcm_sframes_t period_size; //samples per frame`	35	`static snd_pcm_sframes_t period_size; //samples per frame`
39	`static snd_output_t *output = NULL;`	36	`static snd_output_t *output = NULL;`
40		37
41	`static int set_hwparams(snd_pcm_t handle, snd_pcm_hw_params_t params, unsigned int channels)`	38	`static int set_hwparams(snd_pcm_t handle, snd_pcm_hw_params_t params, unsigned int channels)`
42	`{`	39	`{`
43	`unsigned int rrate;`	40	`unsigned int rrate;`
44	`snd_pcm_uframes_t size;`	41	`snd_pcm_uframes_t size;`
45	`int err, dir;`	42	`int err, dir;`
46		43
47	`/* choose all parameters */`	44	`/* choose all parameters */`
48	`err = snd_pcm_hw_params_any(handle, params);`	45	`err = snd_pcm_hw_params_any(handle, params);`
49	`if (err < 0)`	46	`if (err < 0)`
50	`{`	47	`{`
51	`printf("Broken configuration for playback: no configurations available: %s\n", snd_strerror(err));`	48	`printf("Broken configuration for playback: no configurations available: %s\n", snd_strerror(err));`
52	`return err;`	49	`return err;`
53	`}`	50	`}`
54	`/* set hardware resampling */`	51	`/* set hardware resampling */`
55	`err = snd_pcm_hw_params_set_rate_resample(handle, params, resample);`	52	`err = snd_pcm_hw_params_set_rate_resample(handle, params, resample);`
56	`if (err < 0)`	53	`if (err < 0)`
57	`{`	54	`{`
58	`printf("Resampling setup failed for playback: %s\n", snd_strerror(err));`	55	`printf("Resampling setup failed for playback: %s\n", snd_strerror(err));`
59	`return err;`	56	`return err;`
60	`}`	57	`}`
61	`/* set the interleaved read/write format */`	58	`/* set the interleaved read/write format */`
62	`err = snd_pcm_hw_params_set_access(handle, params, SND_PCM_ACCESS_RW_INTERLEAVED);`	59	`err = snd_pcm_hw_params_set_access(handle, params, SND_PCM_ACCESS_RW_INTERLEAVED);`
63	`if (err < 0)`	60	`if (err < 0)`
64	`{`	61	`{`
65	`printf("Access type not available for playback: %s\n", snd_strerror(err));`	62	`printf("Access type not available for playback: %s\n", snd_strerror(err));`
66	`return err;`	63	`return err;`
67	`}`	64	`}`
68	`/* set the sample format */`	65	`/* set the sample format */`
69	`err = snd_pcm_hw_params_set_format(handle, params, format);`	66	`err = snd_pcm_hw_params_set_format(handle, params, format);`
70	`if (err < 0)`	67	`if (err < 0)`
71	`{`	68	`{`
72	`printf("Sample format not available for playback: %s\n", snd_strerror(err));`	69	`printf("Sample format not available for playback: %s\n", snd_strerror(err));`
73	`return err;`	70	`return err;`
74	`}`	71	`}`
75	`/* set the count of channels */`	72	`/* set the count of channels */`
76	`err = snd_pcm_hw_params_set_channels(handle, params, channels);`	73	`err = snd_pcm_hw_params_set_channels(handle, params, channels);`
77	`if (err < 0)`	74	`if (err < 0)`
78	`{`	75	`{`
79	`printf("Channels count (%i) not available for playbacks: %s\n", channels, snd_strerror(err));`	76	`printf("Channels count (%i) not available for playbacks: %s\n", channels, snd_strerror(err));`
80	`return err;`	77	`return err;`
81	`}`	78	`}`
82	`/* set the stream rate */`	79	`/* set the stream rate */`
83	`rrate = rate;`	80	`rrate = rate;`
84	`err = snd_pcm_hw_params_set_rate_near(handle, params, &rrate, 0);`	81	`err = snd_pcm_hw_params_set_rate_near(handle, params, &rrate, 0);`
85	`if (err < 0)`	82	`if (err < 0)`
86	`{`	83	`{`
87	`printf("Rate %iHz not available for playback: %s\n", rate, snd_strerror(err));`	84	`printf("Rate %iHz not available for playback: %s\n", rate, snd_strerror(err));`
88	`return err;`	85	`return err;`
89	`}`	86	`}`
90	`if (rrate != rate)`	87	`if (rrate != rate)`
91	`{`	88	`{`
92	`printf("Rate doesn't match (requested %iHz, get %iHz)\n", rate, err);`	89	`printf("Rate doesn't match (requested %iHz, get %iHz)\n", rate, err);`
93	`return -EINVAL;`	90	`return -EINVAL;`
94	`}`	91	`}`
95	`else printf("Rate set to %i Hz\n", rate, err);`	92	`else printf("Rate set to %i Hz\n", rate, err);`
96	`/* set the buffer time */`	93	`/* set the buffer time */`
97	`err = snd_pcm_hw_params_set_buffer_time_near(handle, params, &buffer_time, &dir);`	94	`err = snd_pcm_hw_params_set_buffer_time_near(handle, params, &buffer_time, &dir);`
98	`if (err < 0)`	95	`if (err < 0)`
99	`{`	96	`{`
100	`printf("Unable to set buffer time %i for playback: %s\n", buffer_time, snd_strerror(err));`	97	`printf("Unable to set buffer time %i for playback: %s\n", buffer_time, snd_strerror(err));`
101	`return err;`	98	`return err;`
102	`}`	99	`}`
103	`err = snd_pcm_hw_params_get_buffer_size(params, &size);`	100	`err = snd_pcm_hw_params_get_buffer_size(params, &size);`
104	`if (err < 0)`	101	`if (err < 0)`
105	`{`	102	`{`
106	`printf("Unable to get buffer size for playback: %s\n", snd_strerror(err));`	103	`printf("Unable to get buffer size for playback: %s\n", snd_strerror(err));`
107	`return err;`	104	`return err;`
108	`}`	105	`}`
109	`buffer_size = size;`	106	`buffer_size = size;`
110	`printf("Bufffer size set to: %d Requested buffer time: %ld \n", (int) buffer_size, (long) buffer_time);`	107	`printf("Bufffer size set to: %d Requested buffer time: %ld \n", (int) buffer_size, (long) buffer_time);`
111		108
112		109
113	`/// set the period time`	110	`/// set the period time`
114	`err = snd_pcm_hw_params_set_period_time_near(handle, params, &period_time, &dir);`	111	`err = snd_pcm_hw_params_set_period_time_near(handle, params, &period_time, &dir);`
115	`if (err < 0)`	112	`if (err < 0)`
116	`{`	113	`{`
117	`printf("Unable to set period time %i for playback: %s\n", period_time, snd_strerror(err));`	114	`printf("Unable to set period time %i for playback: %s\n", period_time, snd_strerror(err));`
118	`return err;`	115	`return err;`
119	`}`	116	`}`
120		117
121	`err = snd_pcm_hw_params_get_period_size(params, &size, &dir);`	118	`err = snd_pcm_hw_params_get_period_size(params, &size, &dir);`
122	`if (err < 0)`	119	`if (err < 0)`
123	`{`	120	`{`
124	`printf("Unable to get period size for playback: %s\n", snd_strerror(err));`	121	`printf("Unable to get period size for playback: %s\n", snd_strerror(err));`
125	`return err;`	122	`return err;`
126	`}`	123	`}`
127	`period_size = size;`	124	`period_size = size;`
128	`printf("Period size set to: %d Requested period time: %ld \n", (int) period_size, (long) period_time);`	125	`printf("Period size set to: %d Requested period time: %ld \n", (int) period_size, (long) period_time);`
129		126
130	`/* write the parameters to device */`	127	`/* write the parameters to device */`
131	`err = snd_pcm_hw_params(handle, params);`	128	`err = snd_pcm_hw_params(handle, params);`
132	`if (err < 0)`	129	`if (err < 0)`
133	`{`	130	`{`
134	`printf("Unable to set hw params for playback: %s\n", snd_strerror(err));`	131	`printf("Unable to set hw params for playback: %s\n", snd_strerror(err));`
135	`return err;`	132	`return err;`
136	`}`	133	`}`
137	`return 0;`	134	`return 0;`
138	`}`	135	`}`
139		136
140	`static int set_swparams(snd_pcm_t handle, snd_pcm_sw_params_t swparams)`	137	`static int set_swparams(snd_pcm_t handle, snd_pcm_sw_params_t swparams)`
141	`{`	138	`{`
142	`int err;`	139	`int err;`
143		140
144	`/* get the current swparams */`	141	`/* get the current swparams */`
145	`err = snd_pcm_sw_params_current(handle, swparams);`	142	`err = snd_pcm_sw_params_current(handle, swparams);`
146	`if (err < 0)`	143	`if (err < 0)`
147	`{`	144	`{`
148	`printf("Unable to determine current swparams for playback: %s\n", snd_strerror(err));`	145	`printf("Unable to determine current swparams for playback: %s\n", snd_strerror(err));`
149	`return err;`	146	`return err;`
150	`}`	147	`}`
151	`// start the transfer when the buffer is almost full: never fou our case`	148	`// start the transfer when the buffer is almost full: never fou our case`
152	`err = snd_pcm_sw_params_set_start_threshold(handle, swparams, 2 * buffer_size);`	149	`err = snd_pcm_sw_params_set_start_threshold(handle, swparams, 2 * buffer_size);`
153	`if (err < 0)`	150	`if (err < 0)`
154	`{`	151	`{`
155	`printf("Unable to set start threshold mode for playback: %s\n", snd_strerror(err));`	152	`printf("Unable to set start threshold mode for playback: %s\n", snd_strerror(err));`
156	`return err;`	153	`return err;`
157	`}`	154	`}`
158		155
159	`err = snd_pcm_sw_params_set_period_event(handle, swparams, 1);`	156	`err = snd_pcm_sw_params_set_period_event(handle, swparams, 1);`
160	`if (err < 0)`	157	`if (err < 0)`
161	`{`	158	`{`
162	`printf("Unable to set period event: %s\n", snd_strerror(err));`	159	`printf("Unable to set period event: %s\n", snd_strerror(err));`
163	`return err;`	160	`return err;`
164	`}`	161	`}`
165		162
166	`/* write the parameters to the playback device */`	163	`/* write the parameters to the playback device */`
167	`err = snd_pcm_sw_params(handle, swparams);`	164	`err = snd_pcm_sw_params(handle, swparams);`
168	`if (err < 0)`	165	`if (err < 0)`
169	`{`	166	`{`
170	`printf("Unable to set sw params for playback: %s\n", snd_strerror(err));`	167	`printf("Unable to set sw params for playback: %s\n", snd_strerror(err));`
171	`return err;`	168	`return err;`
172	`}`	169	`}`
173	`return 0;`	170	`return 0;`
174	`}`	171	`}`
175		172
176	`////// SIGNAL GENERATION STUFF`	173	`////// SIGNAL GENERATION STUFF`
177	`unsigned int linear_windowed_chirp(short *pole)`	174	`unsigned int linear_windowed_chirp(short *pole)`
178	`{`	175	`{`
179	`unsigned int maxval = (1 << (snd_pcm_format_width(format) - 1)) - 1;`	176	`unsigned int maxval = (1 << (snd_pcm_format_width(format) - 1)) - 1;`
180		177
181	`static const float f0 = 5000; //starting frequency`	178	`static const float f0 = 5000; //starting frequency`
182	`static const float fmax = 10000; //ending frequency`	179	`static const float fmax = 10000; //ending frequency`
183	`static const float Tw = 0.0015;`	180	`static const float Tw = 0.0015;`
184	`static float k;`	181	`static float k;`
185		182
186	`unsigned int n=0;`	183	`unsigned int n=0;`
187	`double t;`	184	`double t;`
188	`unsigned int chirp_samples; // number of samples per period`	185	`unsigned int chirp_samples; // number of samples per period`
189		186
190	`k=2*(fmax-f0)/Tw;`	187	`k=2*(fmax-f0)/Tw;`
191	`chirp_samples = ceil(rate*Tw);`	188	`chirp_samples = ceil(rate*Tw);`
192		189
193	`for (n=0;n<=chirp_samples;n++)`	190	`for (n=0;n<=chirp_samples;n++)`
194	`{`	191	`{`
195	`t = (double) n / (double)rate;`	192	`t = (double) n / (double)rate;`
196	`pole[n] = (short) floor( (0.35875 - 0.48829cos(2M_PIt1/Tw) + 0.14128cos(2M_PI2t1/Tw) - 0.01168cos(2M_PI3t1/Tw))maxvalsin(2M_PI(t)(f0+(k/2)(t))) );`	193	`pole[n] = (short) floor( (0.35875 - 0.48829cos(2M_PIt1/Tw) + 0.14128cos(2M_PI2t1/Tw) - 0.01168cos(2M_PI3t1/Tw))maxvalsin(2M_PI(t)(f0+(k/2)(t))) );`
197	`}`	194	`}`
198	`return (chirp_samples);`	195	`return (chirp_samples);`
199	`}`	196	`}`
200		197
201	`int main(int argc, char *argv[])`	198	`int main(int argc, char *argv[])`
202	`{`	199	`{`
203	`snd_pcm_t playback_handle, capture_handle;`	200	`snd_pcm_t playback_handle, capture_handle;`
204	`int err;`	201	`int err;`
205	`snd_pcm_hw_params_t *hwparams;`	202	`snd_pcm_hw_params_t *hwparams;`
206	`snd_pcm_sw_params_t *swparams;`	203	`snd_pcm_sw_params_t *swparams;`
207		204
208	`long int correlationl, correlationr;`	205	`long int correlationl, correlationr;`
-		206	`float *echo_map;`
209	`int L_signal, R_signal;`	207	`int L_signal, R_signal;`
210	`short chirp, signal;`	208	`short chirp, signal;`
211	`float chirp_spect, lecho_spect, *recho_spect;`	209	`float chirp_spect, lecho_spect, *recho_spect;`
212	`float x,y;`	210	`float x,y;`
213	`unsigned int i,j,m,n;`	211	`unsigned int i,j,m,n;`
214	`unsigned int delayl[10],delayr[10]; //store delay of signifed correlation`	212	`unsigned int delayl[10],delayr[10]; //store delay of signifed correlation`
215	`long int l,r; // store correlation at strict time`	213	`long int l,r; // store correlation at strict time`
216	`double df; //frequency resolution`	214	`double df; //frequency resolution`
217	`unsigned int frequency_bins; // number of output frequency bins`	215	`unsigned int frequency_bins; // number of output frequency bins`
218		216
219	`float density_map[MAP_SIZE][MAP_SIZE]; // Array to store two dimensional image of echos`	-
220		-
221	`double *inchirp;`	217	`double *inchirp;`
222	`fftw_complex *outchirp;`	218	`fftw_complex *outchirp;`
223	`fftw_plan fft_plan_chirp;`	219	`fftw_plan fft_plan_chirp;`
224		220
225	`FILE *out;`	221	`FILE *out;`
226		222
227	`snd_pcm_hw_params_alloca(&hwparams);`	223	`snd_pcm_hw_params_alloca(&hwparams);`
228	`snd_pcm_sw_params_alloca(&swparams);`	224	`snd_pcm_sw_params_alloca(&swparams);`
229		225
230	`printf("Simple PC sonar ver. 000000001 starting work.. \n");`	226	`printf("Simple PC sonar $Rev:$ starting work.. \n");`
231		227
232	`//open and set playback device`	228	`//open and set playback device`
233	`if ((err = snd_pcm_open(&playback_handle, device, SND_PCM_STREAM_PLAYBACK, 0)) < 0)`	229	`if ((err = snd_pcm_open(&playback_handle, device, SND_PCM_STREAM_PLAYBACK, 0)) < 0)`
234	`{`	230	`{`
235	`printf("Playback open error: %s\n", snd_strerror(err));`	231	`printf("Playback open error: %s\n", snd_strerror(err));`
236	`return 0;`	232	`return 0;`
237	`}`	233	`}`
238		234
239	`if ((err = set_hwparams(playback_handle, hwparams, 1)) < 0)`	235	`if ((err = set_hwparams(playback_handle, hwparams, 1)) < 0)`
240	`{`	236	`{`
241	`printf("Setting of hwparams failed: %s\n", snd_strerror(err));`	237	`printf("Setting of hwparams failed: %s\n", snd_strerror(err));`
242	`exit(EXIT_FAILURE);`	238	`exit(EXIT_FAILURE);`
243	`}`	239	`}`
244	`if ((err = set_swparams(playback_handle, swparams)) < 0)`	240	`if ((err = set_swparams(playback_handle, swparams)) < 0)`
245	`{`	241	`{`
246	`printf("Setting of swparams failed: %s\n", snd_strerror(err));`	242	`printf("Setting of swparams failed: %s\n", snd_strerror(err));`
247	`exit(EXIT_FAILURE);`	243	`exit(EXIT_FAILURE);`
248	`}`	244	`}`
249		245
250	`//open and set capture device`	246	`//open and set capture device`
251	`if ((err = snd_pcm_open(&capture_handle, device, SND_PCM_STREAM_CAPTURE, 0)) < 0)`	247	`if ((err = snd_pcm_open(&capture_handle, device, SND_PCM_STREAM_CAPTURE, 0)) < 0)`
252	`{`	248	`{`
253	`printf("Playback open error: %s\n", snd_strerror(err));`	249	`printf("Playback open error: %s\n", snd_strerror(err));`
254	`return 0;`	250	`return 0;`
255	`}`	251	`}`
256		252
257	`if ((err = set_hwparams(capture_handle, hwparams, 2)) < 0)`	253	`if ((err = set_hwparams(capture_handle, hwparams, 2)) < 0)`
258	`{`	254	`{`
259	`printf("Setting of hwparams failed: %s\n", snd_strerror(err));`	255	`printf("Setting of hwparams failed: %s\n", snd_strerror(err));`
260	`exit(EXIT_FAILURE);`	256	`exit(EXIT_FAILURE);`
261	`}`	257	`}`
262	`if ((err = set_swparams(capture_handle, swparams)) < 0)`	258	`if ((err = set_swparams(capture_handle, swparams)) < 0)`
263	`{`	259	`{`
264	`printf("Setting of swparams failed: %s\n", snd_strerror(err));`	260	`printf("Setting of swparams failed: %s\n", snd_strerror(err));`
265	`exit(EXIT_FAILURE);`	261	`exit(EXIT_FAILURE);`
266	`}`	262	`}`
267		263
268	`/* err = snd_pcm_link( capture_handle, playback_handle); //link capture and playback together`	264	`/* err = snd_pcm_link( capture_handle, playback_handle); //link capture and playback together`
269	`if (err < 0)`	265	`if (err < 0)`
270	`{`	266	`{`
271	`printf("Device linking error: %s\n", snd_strerror(err));`	267	`printf("Device linking error: %s\n", snd_strerror(err));`
272	`exit(EXIT_FAILURE);`	268	`exit(EXIT_FAILURE);`
273	`}*/`	269	`}*/`
274		270
275	`correlationl = malloc(period_size * sizeof(long int)); //array to store correlation curve`	271	`correlationl = malloc(period_size * sizeof(long int)); //array to store correlation curve`
276	`correlationr = malloc(period_size * sizeof(long int)); //array to store correlation curve`	272	`correlationr = malloc(period_size * sizeof(long int)); //array to store correlation curve`
277	`L_signal = malloc(period_size * sizeof(int));`	273	`L_signal = malloc(period_size * sizeof(int));`
278	`R_signal = malloc(period_size * sizeof(int));`	274	`R_signal = malloc(period_size * sizeof(int));`
279	`chirp = calloc(2*period_size, sizeof(short));`	275	`chirp = calloc(2*period_size, sizeof(short));`
280	`signal = malloc(2period_size sizeof(short));`	276	`signal = malloc(2period_size sizeof(short));`
-		277	`echo_map = malloc(3period_size sizeof(float)); // Array to store two dimensional image of echos`
281		278
282	`// generate ping pattern`	279	`// generate ping pattern`
283	`chirp_size = linear_windowed_chirp(chirp);`	280	`chirp_size = linear_windowed_chirp(chirp);`
284		281
285	`frequency_bins = chirp_size / 2 + 1;`	282	`frequency_bins = chirp_size / 2 + 1;`
286	`df = (double) rate / (double) chirp_size;`	283	`df = (double) rate / (double) chirp_size;`
287	`chirp_spect = malloc(frequency_bins * sizeof(float));`	284	`chirp_spect = malloc(frequency_bins * sizeof(float));`
288	`lecho_spect = malloc(frequency_bins * sizeof(float));`	285	`lecho_spect = malloc(frequency_bins * sizeof(float));`
289	`recho_spect = malloc(frequency_bins * sizeof(float));`	286	`recho_spect = malloc(frequency_bins * sizeof(float));`
290		287
291	`inchirp = fftw_malloc(sizeof(double) * chirp_size); // allocate input array for FFT`	288	`inchirp = fftw_malloc(sizeof(double) * chirp_size); // allocate input array for FFT`
292	`outchirp = fftw_malloc(sizeof(fftw_complex) * frequency_bins);`	289	`outchirp = fftw_malloc(sizeof(fftw_complex) * frequency_bins);`
293		290
294	`fft_plan_chirp = fftw_plan_dft_r2c_1d(chirp_size, inchirp, outchirp, FFTW_ESTIMATE);`	291	`fft_plan_chirp = fftw_plan_dft_r2c_1d(chirp_size, inchirp, outchirp, FFTW_ESTIMATE);`
295		292
296	`printf("compute chirp spectrum\n");`	293	`printf("compute chirp spectrum\n");`
297	`for(i=0; i < chirp_size; i++) inchirp[i] = chirp[i];`	294	`for(i=0; i < chirp_size; i++) inchirp[i] = chirp[i];`
298	`fftw_execute(fft_plan_chirp);`	295	`fftw_execute(fft_plan_chirp);`
299	`for(i=0; i < frequency_bins; i++) chirp_spect[i] = sqrt( outchirp[i][0] * outchirp[i][0] + outchirp[i][1] * outchirp[i][1] );`	296	`for(i=0; i < frequency_bins; i++) chirp_spect[i] = sqrt( outchirp[i][0] * outchirp[i][0] + outchirp[i][1] * outchirp[i][1] );`
300		297
301	`// write chirp data to souncard buffer`	298	`// write chirp data to souncard buffer`
302	`err = snd_pcm_writei(playback_handle, chirp, period_size);`	299	`err = snd_pcm_writei(playback_handle, chirp, period_size);`
303	`if (err < 0)`	300	`if (err < 0)`
304	`{`	301	`{`
305	`printf("Initial write error: %s\n", snd_strerror(err));`	302	`printf("Initial write error: %s\n", snd_strerror(err));`
306	`exit(EXIT_FAILURE);`	303	`exit(EXIT_FAILURE);`
307	`}`	304	`}`
308		305
309	`//start sream`	306	`//start sream`
310	`err = snd_pcm_start(playback_handle);`	307	`err = snd_pcm_start(playback_handle);`
311	`if (err < 0)`	308	`if (err < 0)`
312	`{`	309	`{`
313	`printf("Start error: %s\n", snd_strerror(err));`	310	`printf("Start error: %s\n", snd_strerror(err));`
314	`exit(EXIT_FAILURE);`	311	`exit(EXIT_FAILURE);`
315	`}`	312	`}`
316		313
317	`err = snd_pcm_start(capture_handle);`	314	`err = snd_pcm_start(capture_handle);`
318	`if (err < 0)`	315	`if (err < 0)`
319	`{`	316	`{`
320	`printf("Start error: %s\n", snd_strerror(err));`	317	`printf("Start error: %s\n", snd_strerror(err));`
321	`exit(EXIT_FAILURE);`	318	`exit(EXIT_FAILURE);`
322	`}`	319	`}`
323	`else printf("Transmitting all samples of chirp\n");`	320	`else printf("Transmitting all samples of chirp\n");`
324	`//--------------`	321	`//--------------`
325		322
326	`while ( snd_pcm_avail_update(capture_handle) < period_size) // wait for one period of data`	323	`while ( snd_pcm_avail_update(capture_handle) < period_size) // wait for one period of data`
327	`{`	324	`{`
328	`usleep(1000);`	325	`usleep(1000);`
329	`printf(".");`	326	`printf(".");`
330	`}`	327	`}`
331		328
332	`err = snd_pcm_drop(playback_handle); // stop audio stream`	329	`err = snd_pcm_drop(playback_handle); // stop audio stream`
333	`err = snd_pcm_drain(capture_handle);`	330	`err = snd_pcm_drain(capture_handle);`
334	`if (err < 0)`	331	`if (err < 0)`
335	`{`	332	`{`
336	`printf("Stop error: %s\n", snd_strerror(err));`	333	`printf("Stop error: %s\n", snd_strerror(err));`
337	`exit(EXIT_FAILURE);`	334	`exit(EXIT_FAILURE);`
338	`}`	335	`}`
339		336
340	`err = snd_pcm_readi(capture_handle, signal, period_size); //read period from audio buffer`	337	`err = snd_pcm_readi(capture_handle, signal, period_size); //read period from audio buffer`
341	`if (err < 0)`	338	`if (err < 0)`
342	`{`	339	`{`
343	`printf("Read error: %s\n", snd_strerror(err));`	340	`printf("Read error: %s\n", snd_strerror(err));`
344	`exit(EXIT_FAILURE);`	341	`exit(EXIT_FAILURE);`
345	`}`	342	`}`
346		343
347	`j=0;`	344	`j=0;`
348	`for (i=0;i < period_size;i++) // separe inretleaved samples to two arrays`	345	`for (i=0;i < period_size;i++) // separe inretleaved samples to two arrays`
349	`{`	346	`{`
350	`L_signal[i]=signal[j];`	347	`L_signal[i]=signal[j];`
351	`R_signal[i]=signal[j+1];`	348	`R_signal[i]=signal[j+1];`
352	`j+=2;`	349	`j+=2;`
353	`}`	350	`}`
354		351
355	`printf("\nData transmitted \ncorrelating\n");`	352	`printf("\nData transmitted \ncorrelating\n");`
356	`for (n=0; n < (period_size - chirp_size - 1); n++)`	353	`for (n=0; n < (period_size - chirp_size - 1); n++)`
357	`{`	354	`{`
358	`l=0;`	355	`l=0;`
359	`r=0;`	356	`r=0;`
360	`for ( m = 0; m < chirp_size;m++)`	357	`for ( m = 0; m < chirp_size;m++)`
361	`{`	358	`{`
362	`l += chirp[m]*L_signal[m+n]; // correlate with left channel`	359	`l += chirp[m]*L_signal[m+n]; // correlate with left channel`
363	`r += chirp[m]*R_signal[m+n]; // correlate with right channel`	360	`r += chirp[m]*R_signal[m+n]; // correlate with right channel`
364	`}`	361	`}`
365	`correlationl[n]=abs(l);`	362	`correlationl[n]=abs(l);`
366	`correlationr[n]=abs(r);`	363	`correlationr[n]=abs(r);`
367	`}`	364	`}`
368		365
-		366	`m=0;`
369	`printf("Building echo map\n"); // compute map from left and right correlation data`	367	`printf("Building echo map\n"); // compute map from left and right correlation data`
370	`for (i=0;i < MAP_SIZE; i++)`	-
371	`{`	-
372		-
373	`for (j=0;j < MAP_SIZE; j++)`	368	`for (i=0;i < period_size; i++)`
374	`{`	369	`{`
375	`x=(float)iRESOLUTION; y=(float)jRESOLUTION; //transofm integger index of array to float with appproopirate resolution`	370	`for(j=0;j < period_size; j++)`
376		371	`{`
-		372	`echo_map[m]=(ii-jj+APERTUREAPERTURE)/(2APERTURE);`
377	`density_map[i][j]=(float)correlationl[(int)sqrt(xx + yy)]correlationr[(int)sqrt(APERTUREAPERTURE - 2APERTUREx + xx + yy)];`	373	`echo_map[m+1]=sqrt(-(i-j-APERTURE)(i+j-APERTURE)(i-j+APERTURE)(i+j+APERTURE))/(2r);`
-		374	`echo_map[m+2]=correlationl[i]*correlationr[j];`
-		375	`m+=3;`
-		376	`}`
378	`}`	377	`}`
379	`}`	-
380		378
381		379
382	`printf("Searching echos\n");`	380	`printf("Searching echos\n");`
383	`r=0;`	381	`r=0;`
384	`l=0;`	382	`l=0;`
385	`for (n=0; n < period_size;n++) //najde nejvetsi korelace`	383	`for (n=0; n < period_size;n++) //najde nejvetsi korelace`
386	`{`	384	`{`
387	`if (l < correlationl[n])`	385	`if (l < correlationl[n])`
388	`{`	386	`{`
389	`delayl[1] = n;`	387	`delayl[1] = n;`
390	`l = correlationl[n];`	388	`l = correlationl[n];`
391	`}`	389	`}`
392	`if (r < correlationr[n])`	390	`if (r < correlationr[n])`
393	`{`	391	`{`
394	`delayr[1] = n;`	392	`delayr[1] = n;`
395	`r = correlationr[n];`	393	`r = correlationr[n];`
396	`}`	394	`}`
397	`}`	395	`}`
398		396
399	`//spocitejj frekvencni spektrum pro levy kanal`	397	`//spocitej frekvencni spektrum pro levy kanal`
400	`for(i=delayl[1]; i < delayl[1] + chirp_size; i++) inchirp[i-delayl[1]] = L_signal[i];`	398	`for(i=delayl[1]; i < delayl[1] + chirp_size; i++) inchirp[i-delayl[1]] = L_signal[i];`
401	`fftw_execute(fft_plan_chirp);`	399	`fftw_execute(fft_plan_chirp);`
402	`for(i=0; i < frequency_bins; i++) lecho_spect[i] = sqrt(outchirp[i][0] * outchirp[i][0] + outchirp[i][1] * outchirp[i][1]);`	400	`for(i=0; i < frequency_bins; i++) lecho_spect[i] = sqrt(outchirp[i][0] * outchirp[i][0] + outchirp[i][1] * outchirp[i][1]);`
403		401
404		402
405	`// napln pole daty z praveho kanalu a spocitej frekvencni spektrum`	403	`// napln pole daty z praveho kanalu a spocitej frekvencni spektrum`
406	`for(i=delayr[1]; i < delayr[1] + chirp_size; i++) inchirp[i-delayr[1]] = R_signal[i];`	404	`for(i=delayr[1]; i < delayr[1] + chirp_size; i++) inchirp[i-delayr[1]] = R_signal[i];`
407	`fftw_execute(fft_plan_chirp);`	405	`fftw_execute(fft_plan_chirp);`
408	`for(i=0; i < frequency_bins; i++) recho_spect[i] = sqrt(outchirp[i][0] * outchirp[i][0] + outchirp[i][1] * outchirp[i][1]);`	406	`for(i=0; i < frequency_bins; i++) recho_spect[i] = sqrt(outchirp[i][0] * outchirp[i][0] + outchirp[i][1] * outchirp[i][1]);`
409		407
410	`printf("Writing output files\n");`	408	`printf("Writing output files\n");`
411	`out=fopen("/tmp/sonar.txt","w");`	409	`out=fopen("/tmp/sonar.txt","w");`
412	`for (i=0; i <= (period_size - 1); i++)`	410	`for (i=0; i <= (period_size - 1); i++)`
413	`{`	411	`{`
414	`fprintf(out,"%2.3f %6d %6d %9ld %9ld\n",SOUND_SPEED * (float) i / rate,L_signal[i],R_signal[i],correlationl[i], correlationr[i]);`	412	`fprintf(out,"%2.3f %6d %6d %9ld %9ld\n",SOUND_SPEED * (float) i / rate,L_signal[i],R_signal[i],correlationl[i], correlationr[i]);`
415	`}`	413	`}`
416	`fclose(out);`	414	`fclose(out);`
417		415
-		416	`j=0;`
418	`out=fopen("/tmp/plane_cut.txt","w"); // writes plane cut - e.g. density map to file`	417	`out=fopen("/tmp/plane_cut.txt","w"); // writes plane cut - e.g. density map to file`
419	`for (i=0;i < MAP_SIZE; i++)`	418	`for (i=0;i < period_size; i++)`
420	`{`	419	`{`
421	`for (j=0;j < MAP_SIZE; j++) fprintf(out,"%3.2f ", density_map);`	420	`fprintf(out,"%3.2f %3.2f %3.2f\n", echo_map[j], echo_map[j+1], echo_map[j+2]);`
422	`fprintf(out,"\n");`	421	`j+=3;`
423	`}`	422	`}`
424		423
425	`out=fopen("/tmp/chirp.txt","w");`	424	`out=fopen("/tmp/chirp.txt","w");`
426	`for (i=0; i <= (chirp_size - 1); i++)`	425	`for (i=0; i <= (chirp_size - 1); i++)`
427	`{`	426	`{`
428	`fprintf(out,"%6d %6d\n", i, chirp[i]);`	427	`fprintf(out,"%6d %6d\n", i, chirp[i]);`
429	`}`	428	`}`
430	`fclose(out);`	429	`fclose(out);`
431		430
432	`out=fopen("/tmp/echo.txt","w");`	431	`out=fopen("/tmp/echo.txt","w");`
433	`for(i=0; i < chirp_size; i++) fprintf(out,"%6d %6d %6d\n", i, L_signal[i + delayl[1]], R_signal[i + delayr[1]]);`	432	`for(i=0; i < chirp_size; i++) fprintf(out,"%6d %6d %6d\n", i, L_signal[i + delayl[1]], R_signal[i + delayr[1]]);`
434	`fclose(out);`	433	`fclose(out);`
435		434
436	`out=fopen("/tmp/spektra.txt","w");`	435	`out=fopen("/tmp/spektra.txt","w");`
437	`for (i=0; i < frequency_bins; i++)`	436	`for (i=0; i < frequency_bins; i++)`
438	`{`	437	`{`
439	`fprintf(out,"%4.3f %4.3f %4.3f %4.3f\n", (i+0.5) * df, chirp_spect[i], lecho_spect[i], recho_spect[i]);`	438	`fprintf(out,"%4.3f %4.3f %4.3f %4.3f\n", (i+0.5) * df, chirp_spect[i], lecho_spect[i], recho_spect[i]);`
440	`}`	439	`}`
441	`fclose(out);`	440	`fclose(out);`
442		441
443	`free(correlationl);`	442	`free(correlationl);`
444	`free(correlationr);`	443	`free(correlationr);`
445	`free(L_signal);`	444	`free(L_signal);`
446	`free(R_signal);`	445	`free(R_signal);`
447	`free(chirp);`	446	`free(chirp);`
448	`free(signal);`	447	`free(signal);`
-		448	`free(echo_map);`
449		449
450	`snd_pcm_close(playback_handle);`	450	`snd_pcm_close(playback_handle);`
451	`snd_pcm_close(capture_handle);`	451	`snd_pcm_close(capture_handle);`
452	`return 0;`	452	`return 0;`
453	`}`	453	`}`
454		454

Subversion Repositories svnkaklik

(root)/programy/C/ix86/echo/SW/sonar/src/sonar.c – Rev 645 → 646