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

 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 int verbose = 0;					/* verbose flag */
 static int resample = 1;				/* enable alsa-lib resampling */
 static int period_event = 0;				/* produce poll event after each period */
 #define SOUND_SPEED	340
 #define SIGNAL_SAMPLES 100000
 // 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 maxval = (1 << (snd_pcm_format_width(format) - 1)) - 1;
-static const float f0 = 1000;
+static const float f0 = 1000;		//starting frequency
-static const float fmax = 7000;
+static const float fmax = 7000;		//ending frequency
 static const float Tw = 0.002;
 static float k;
 unsigned int n=0;
 double t;
 /////////// CALL BACK STUFF ///////////////////
 static void async_playback_callback(snd_async_handler_t *ahandler)
+{
 	snd_pcm_t *handle = snd_async_handler_get_pcm(ahandler);
-/*	struct async_private_data *data = snd_async_handler_get_callback_private(ahandler);
-	signed short *samples = data->samples;
-	snd_pcm_channel_area_t *areas = data->areas;*/
 	snd_pcm_sframes_t avail;
 	int err;
 	avail = snd_pcm_avail_update(handle);
 	while ((avail >= period_size) && ((period*period_size) < chirp_size) ) {
+}
 static void async_capture_callback(snd_async_handler_t *ahandler)
+{
 	snd_pcm_t *handle = snd_async_handler_get_pcm(ahandler);
-/*	struct async_private_data *data = snd_async_handler_get_callback_private(ahandler);
-	signed short *samples = data->samples;
-	snd_pcm_channel_area_t *areas = data->areas;*/
 	snd_pcm_sframes_t avail;
 	int err;
 	avail = snd_pcm_avail_update(handle);
 	while ((avail >= period_size) /*&& ((period*period_size) < (CHIRP_SIZE-100))*/ ) {  // segmentation fault checking disabled
 	if ((err = set_swparams(capture_handle, swparams)) < 0) {
 		printf("Setting of swparams failed: %s\n", snd_strerror(err));
 		exit(EXIT_FAILURE);
+	}
-/// generate ping pattern
+// generate ping pattern
         chirp_size=linear_windowed_chirp(chirp,1000000, CHIRP_OFFSET);
-/// register playback callback
+// register playback callback
 	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) {
 			printf("Initial write error: %s\n", snd_strerror(err));
 			exit(EXIT_FAILURE);
+		}
 		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) {
 		printf("Unable to register async handler\n");
 	  delay[2] = n;
 	  r = correlationr[n];
+	  }
+	}
-  out=fopen("./output.txt","w");
+  out=fopen("/tmp/sonar.txt","w");
   j=0;
   for(i=0;i<=100000;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;
+  }

Subversion Repositories svnkaklik

(root)/programy/C/ix86/echo/SW/sonar/src/sonar.c @ 640 – Rev 558 → 560