| 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; |