8magsvn – Diff between revs 29 and 31

Subversion Repositories:
Rev:
Show entire file – Ignore whitespace
Rev 29 Rev 31
Line 14... Line 14...
14 #include <math.h> 14 #include <math.h>
15 #include <fftw3.h> 15 #include <fftw3.h>
16   16  
17 static char *device = "plughw:0,0"; /* playback device */ 17 static char *device = "plughw:0,0"; /* playback device */
18 static snd_pcm_format_t format = SND_PCM_FORMAT_S16; /* sample format */ 18 static snd_pcm_format_t format = SND_PCM_FORMAT_S16; /* sample format */
19 static unsigned int rate = 24000; /* stream rate */ 19 static unsigned int rate = 48000; /* stream rate */
20 //static unsigned int buffer_size = 200000; /* ring buffer length in us */ -  
21 //static unsigned int period_size = 10000; /* period time in us */ -  
22 static int verbose = 0; /* verbose flag */ -  
23 static int resample = 1; /* enable alsa-lib resampling */ 20 static int resample = 1; /* enable alsa-lib resampling */
24 static int period_event = 0; /* produce poll event after each period */ 21 static int period_event = 0; /* produce poll event after each period */
25   22  
26 static snd_pcm_sframes_t buffer_size=7008; // size of buffer at sound card 23 static snd_pcm_sframes_t buffer_size=7008; // size of buffer at sound card
27 static snd_pcm_sframes_t period_size=3504; //samples per frame 24 static snd_pcm_sframes_t period_size=2336; //samples per frame
28 static snd_output_t *output = NULL; 25 static snd_output_t *output = NULL;
29 26
30 FILE *out; 27 FILE *out;
31   28  
32 double df; //frequency resolution 29 double df; //frequency resolution
Line 37... Line 34...
37 fftw_plan fft_plan_left, fft_plan_right; 34 fftw_plan fft_plan_left, fft_plan_right;
38   35  
39 double *spect_avg_left, *spect_avg_right; 36 double *spect_avg_left, *spect_avg_right;
40 unsigned int period; 37 unsigned int period;
41   38  
-   39 #define PERIODS 50 // number of periods to average
-   40  
-   41  
42 static int set_hwparams(snd_pcm_t *handle, snd_pcm_hw_params_t *params, unsigned int channels) 42 static int set_hwparams(snd_pcm_t *handle, snd_pcm_hw_params_t *params, unsigned int channels)
43 { 43 {
44 unsigned int rrate; 44 unsigned int rrate;
45 snd_pcm_uframes_t size; 45 snd_pcm_uframes_t size;
46 int err, dir; 46 int err, dir;
Line 175... Line 175...
175 static void async_capture_callback(snd_async_handler_t *ahandler) 175 static void async_capture_callback(snd_async_handler_t *ahandler)
176 { 176 {
177 snd_pcm_t *handle = snd_async_handler_get_pcm(ahandler); 177 snd_pcm_t *handle = snd_async_handler_get_pcm(ahandler);
178 int err; 178 int err;
179 unsigned int i, n; 179 unsigned int i, n;
180 short signal[300000]; 180 short signal[30000];
181   181  
182 /*signal = calloc( (unsigned int) period_size, sizeof(short) ); 182 /*signal = calloc( (unsigned int) period_size, sizeof(short) );
183 if (signal = NULL) printf("memory allocation failed");*/ 183 if (signal = NULL) printf("memory allocation failed");*/
184   184  
185 while (snd_pcm_avail_update(handle) >= period_size) { // read until data is ready in buffer 185 while (snd_pcm_avail_update(handle) >= period_size) { // read until data is ready in buffer
Line 195... Line 195...
195 } 195 }
196   196  
197 n=0; 197 n=0;
198 i=0; 198 i=0;
199 do { 199 do {
200 inl[n]= signal[i]; 200 inl[n]= signal[i]/32768.0;
201 inr[n]= signal[i+1]; 201 inr[n]= signal[i+1]/32768.0;
202 n++; 202 n++;
203 i+=2; 203 i+=2;
204 } while (n < period_size); 204 } while (n < period_size);
205   205  
206 fftw_execute(fft_plan_left); 206 fftw_execute(fft_plan_left);
Line 209... Line 209...
209 for(i=0; i < frequency_bins; i++) spect_avg_left[i] += sqrt( (outl[i][0] * outl[i][0]) + (outl[i][1] * outl[i][1]) ); //acumulate average spectrum 209 for(i=0; i < frequency_bins; i++) spect_avg_left[i] += sqrt( (outl[i][0] * outl[i][0]) + (outl[i][1] * outl[i][1]) ); //acumulate average spectrum
210 for(i=0; i < frequency_bins; i++) spect_avg_right[i] += sqrt( (outr[i][0] * outr[i][0]) + (outr[i][1] * outr[i][1]) ); //acumulate average spectrum 210 for(i=0; i < frequency_bins; i++) spect_avg_right[i] += sqrt( (outr[i][0] * outr[i][0]) + (outr[i][1] * outr[i][1]) ); //acumulate average spectrum
211 period++; 211 period++;
212 } 212 }
213   213  
214 if (period > 100) 214 if (period > PERIODS)
215 { 215 {
216 for(i=0; i < frequency_bins; i++) spect_avg_left[i] = spect_avg_left[i]/100; 216 for(i=0; i < frequency_bins; i++) spect_avg_left[i] = spect_avg_left[i]/PERIODS; // finally average spectrum data
217 for(i=0; i < frequency_bins; i++) spect_avg_right[i] = spect_avg_right[i]/100; 217 for(i=0; i < frequency_bins; i++) spect_avg_right[i] = spect_avg_right[i]/PERIODS;
218   218  
219 out=fopen("/tmp/sidspect","w"); 219 out=fopen("/tmp/sidspec","w");
220   220  
221 for(i=0; i < frequency_bins; i++) 221 for(i=0; i < frequency_bins; i++) //write spectrum to file
222 { 222 {
223 fprintf(out,"%6f %6f %6f\n",(i+0.5)*df, spect_avg_left[i], spect_avg_right[i]); 223 fprintf(out,"%.5e %.5e %.5e\n",(i+0.5)*df, spect_avg_left[i], spect_avg_right[i]);
224 spect_avg_left[i]=0; 224 spect_avg_left[i]=0;
225 spect_avg_right[i]=0; 225 spect_avg_right[i]=0;
226 } 226 }
227 fclose(out); 227 fclose(out);
228 period=0; 228 period=0;
Line 277... Line 277...
277 exit(EXIT_FAILURE); 277 exit(EXIT_FAILURE);
278 } 278 }
279   279  
280 // setup fft 280 // setup fft
281   281  
282 df = (double) rate/ (double) frequency_bins * 2.0; 282 df = (double) rate/ (double) period_size;
283   283  
284 inl = fftw_malloc(sizeof(double) * period_size); // period_size); 284 inl = fftw_malloc(sizeof(double) * period_size); // period_size);
285 outl = fftw_malloc(sizeof(fftw_complex) * frequency_bins); 285 outl = fftw_malloc(sizeof(fftw_complex) * frequency_bins);
286   286  
287 inr = fftw_malloc(sizeof(double) * period_size); // period_size); 287 inr = fftw_malloc(sizeof(double) * period_size); // period_size);