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kaklik |
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/*
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* This small demo sends a simple sinusoidal wave to your speakers.
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*/
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <sched.h>
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#include <errno.h>
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#include <getopt.h>
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#include <alsa/asoundlib.h>
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#include <sys/time.h>
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#include <math.h>
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static char *device = "plughw:0,0"; /* playback device */
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static snd_pcm_format_t format = SND_PCM_FORMAT_S16; /* sample format */
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static unsigned int rate = 44100; /* stream rate */
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static unsigned int channels = 1; /* count of channels */
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static unsigned int buffer_time = 500000; /* ring buffer length in us */
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static unsigned int period_time = 100000; /* period time in us */
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static double freq = 440; /* sinusoidal wave frequency in Hz */
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static int verbose = 0; /* verbose flag */
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static int resample = 1; /* enable alsa-lib resampling */
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static int period_event = 0; /* produce poll event after each period */
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kaklik |
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#define CHIRP_SIZE 1000000
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kaklik |
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int period=0;
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kaklik |
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int cperiod=0;
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short chirp[CHIRP_SIZE];
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short signal[44100*6]; // record 6s of input samples
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kaklik |
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static snd_pcm_sframes_t buffer_size; // size of buffer at sound card
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static snd_pcm_sframes_t period_size; //samples per frame
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static snd_output_t *output = NULL;
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/*static void generate_sine(const snd_pcm_channel_area_t *areas,
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snd_pcm_uframes_t offset,
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int count, double *_phase)
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{
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static double max_phase = 2. * M_PI;
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double phase = *_phase;
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double step = max_phase*freq/(double)rate;
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double res;
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unsigned char *samples[channels], *tmp;
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int steps[channels];
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unsigned int chn, byte;
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union {
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int i;
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unsigned char c[4];
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} ires;
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unsigned int maxval = (1 << (snd_pcm_format_width(format) - 1)) - 1;
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int bps = snd_pcm_format_width(format) / 8; /* bytes per sample */
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/* verify and prepare the contents of areas
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for (chn = 0; chn < channels; chn++) {
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if ((areas[chn].first % 8) != 0) {
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printf("areas[%i].first == %i, aborting...\n", chn, areas[chn].first);
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exit(EXIT_FAILURE);
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}
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samples[chn] = /*(signed short *)(((unsigned char *)areas[chn].addr) + (areas[chn].first / 8));
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if ((areas[chn].step % 16) != 0) {
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printf("areas[%i].step == %i, aborting...\n", chn, areas[chn].step);
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exit(EXIT_FAILURE);
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}
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steps[chn] = areas[chn].step / 8;
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samples[chn] += offset * steps[chn];
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}
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/* fill the channel areas
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while (count-- > 0) {
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res = sin(phase) * maxval;
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ires.i = res;
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tmp = ires.c;
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for (chn = 0; chn < channels; chn++) {
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for (byte = 0; byte < (unsigned int)bps; byte++)
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*(samples[chn] + byte) = tmp[byte];
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samples[chn] += steps[chn];
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}
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phase += step;
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if (phase >= max_phase)
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phase -= max_phase;
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}
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*_phase = phase;
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}*/
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static int set_hwparams(snd_pcm_t *handle,
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snd_pcm_hw_params_t *params,
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snd_pcm_access_t access)
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{
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unsigned int rrate;
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snd_pcm_uframes_t size;
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int err, dir;
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/* choose all parameters */
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err = snd_pcm_hw_params_any(handle, params);
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if (err < 0) {
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printf("Broken configuration for playback: no configurations available: %s\n", snd_strerror(err));
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return err;
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}
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/* set hardware resampling */
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err = snd_pcm_hw_params_set_rate_resample(handle, params, resample);
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if (err < 0) {
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printf("Resampling setup failed for playback: %s\n", snd_strerror(err));
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return err;
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}
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/* set the interleaved read/write format */
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err = snd_pcm_hw_params_set_access(handle, params, access);
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if (err < 0) {
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printf("Access type not available for playback: %s\n", snd_strerror(err));
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return err;
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}
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/* set the sample format */
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err = snd_pcm_hw_params_set_format(handle, params, format);
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if (err < 0) {
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printf("Sample format not available for playback: %s\n", snd_strerror(err));
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return err;
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}
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/* set the count of channels */
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err = snd_pcm_hw_params_set_channels(handle, params, channels);
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if (err < 0) {
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printf("Channels count (%i) not available for playbacks: %s\n", channels, snd_strerror(err));
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return err;
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}
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/* set the stream rate */
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rrate = rate;
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err = snd_pcm_hw_params_set_rate_near(handle, params, &rrate, 0);
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if (err < 0) {
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printf("Rate %iHz not available for playback: %s\n", rate, snd_strerror(err));
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return err;
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}
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if (rrate != rate) {
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printf("Rate doesn't match (requested %iHz, get %iHz)\n", rate, err);
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return -EINVAL;
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}
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/* set the buffer time */
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err = snd_pcm_hw_params_set_buffer_time_near(handle, params, &buffer_time, &dir);
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if (err < 0) {
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printf("Unable to set buffer time %i for playback: %s\n", buffer_time, snd_strerror(err));
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return err;
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}
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err = snd_pcm_hw_params_get_buffer_size(params, &size);
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if (err < 0) {
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printf("Unable to get buffer size for playback: %s\n", snd_strerror(err));
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return err;
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}
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buffer_size = size;
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/* set the period time */
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err = snd_pcm_hw_params_set_period_time_near(handle, params, &period_time, &dir);
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if (err < 0) {
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printf("Unable to set period time %i for playback: %s\n", period_time, snd_strerror(err));
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return err;
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}
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err = snd_pcm_hw_params_get_period_size(params, &size, &dir);
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if (err < 0) {
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printf("Unable to get period size for playback: %s\n", snd_strerror(err));
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return err;
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}
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period_size = size;
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/* write the parameters to device */
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err = snd_pcm_hw_params(handle, params);
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if (err < 0) {
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printf("Unable to set hw params for playback: %s\n", snd_strerror(err));
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return err;
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}
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return 0;
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}
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static int set_swparams(snd_pcm_t *handle, snd_pcm_sw_params_t *swparams)
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{
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int err;
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/* get the current swparams */
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err = snd_pcm_sw_params_current(handle, swparams);
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if (err < 0) {
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printf("Unable to determine current swparams for playback: %s\n", snd_strerror(err));
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return err;
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}
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/* start the transfer when the buffer is almost full: */
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/* (buffer_size / avail_min) * avail_min */
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err = snd_pcm_sw_params_set_start_threshold(handle, swparams, (buffer_size / period_size) * period_size);
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if (err < 0) {
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printf("Unable to set start threshold mode for playback: %s\n", snd_strerror(err));
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return err;
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}
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/* allow the transfer when at least period_size samples can be processed */
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/* or disable this mechanism when period event is enabled (aka interrupt like style processing) */
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err = snd_pcm_sw_params_set_avail_min(handle, swparams, period_event ? buffer_size : period_size);
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if (err < 0) {
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printf("Unable to set avail min for playback: %s\n", snd_strerror(err));
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return err;
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}
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/* enable period events when requested */
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if (period_event) {
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err = snd_pcm_sw_params_set_period_event(handle, swparams, 1);
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if (err < 0) {
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printf("Unable to set period event: %s\n", snd_strerror(err));
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return err;
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}
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}
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/* write the parameters to the playback device */
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err = snd_pcm_sw_params(handle, swparams);
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if (err < 0) {
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printf("Unable to set sw params for playback: %s\n", snd_strerror(err));
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return err;
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}
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return 0;
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}
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struct async_private_data {
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signed short *samples;
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snd_pcm_channel_area_t *areas;
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unsigned int period;
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};
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/*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;
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static const float k = 0.00001;
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int t;
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// if((spozdeni+delka) < delka_pole)
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for(t=0;t < delka_pole;t++) pole[t] = round ( 10000*sin(2*M_PI*(t+faze)*(f0+(k/2)*(t+faze))) );
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faze +=t;
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// else return 0;
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kaklik |
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}*/
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kaklik |
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kaklik |
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kaklik |
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int linear_windowed_chirp(int *pole, int delka_pole){ // vygeneruje linearni chirp a vzorky ulozi do pole
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kaklik |
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unsigned int maxval = (1 << (snd_pcm_format_width(format) - 1)) - 1;
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kaklik |
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kaklik |
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static const float f0 = 1/1000;
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static const float fmax = 1/10000;
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static const float Tw = 10;
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kaklik |
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kaklik |
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static float k;
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kaklik |
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kaklik |
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//k=2*(fmax-Tw*f0)/Tw*Tw;
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k=1/10000;
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kaklik |
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kaklik |
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int n;
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double t;
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for(n=0;n < delka_pole;n++){
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t=n*1/rate;
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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))) );
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}
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}
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kaklik |
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int sine(int *pole, int delka_pole)
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{
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kaklik |
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unsigned int maxval = (1 << (snd_pcm_format_width(format) - 1)) - 1;
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kaklik |
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int t;
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kaklik |
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for(t=0;t < delka_pole;t++) pole[t] = (short) round(maxval*sin( (double)(t)/10.0));
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kaklik |
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}
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static void async_playback_callback(snd_async_handler_t *ahandler)
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{
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snd_pcm_t *handle = snd_async_handler_get_pcm(ahandler);
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kaklik |
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/* struct async_private_data *data = snd_async_handler_get_callback_private(ahandler);
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kaklik |
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signed short *samples = data->samples;
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kaklik |
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snd_pcm_channel_area_t *areas = data->areas;*/
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kaklik |
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snd_pcm_sframes_t avail;
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int err;
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avail = snd_pcm_avail_update(handle);
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kaklik |
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while ((avail >= period_size) && ((period*period_size) < (CHIRP_SIZE-100)) ) {
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kaklik |
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kaklik |
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err = snd_pcm_writei(handle, (chirp+period*period_size), period_size);
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kaklik |
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if (err < 0) {
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printf("Write error: %s\n", snd_strerror(err));
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exit(EXIT_FAILURE);
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}
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if (err != period_size) {
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printf("Write error: written %i expected %li\n", err, period_size);
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exit(EXIT_FAILURE);
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}
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avail = snd_pcm_avail_update(handle);
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kaklik |
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period++;
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kaklik |
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}
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}
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kaklik |
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static void async_capture_callback(snd_async_handler_t *ahandler)
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{
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snd_pcm_t *handle = snd_async_handler_get_pcm(ahandler);
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/* struct async_private_data *data = snd_async_handler_get_callback_private(ahandler);
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signed short *samples = data->samples;
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snd_pcm_channel_area_t *areas = data->areas;*/
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snd_pcm_sframes_t avail;
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int err;
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avail = snd_pcm_avail_update(handle);
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// while ((avail >= period_size) /*&& ((period*period_size) < (CHIRP_SIZE-100))*/ ) {
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err = snd_pcm_readi(handle, (signal+cperiod*period_size), period_size);
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if (err < 0) {
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printf("Read error: %s\n", snd_strerror(err));
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exit(EXIT_FAILURE);
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}
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if (err != period_size) {
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printf("Read error: red %i expected %li\n", err, period_size);
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exit(EXIT_FAILURE);
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}
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avail = snd_pcm_avail_update(handle);
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cperiod++;
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// }
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}
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kaklik |
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int main(int argc, char *argv[])
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{
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snd_pcm_t *playback_handle, *capture_handle;
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int err;
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snd_pcm_hw_params_t *hwparams;
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snd_pcm_sw_params_t *swparams;
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signed short *frame; // pointer to array of samples
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unsigned int chn;
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snd_pcm_channel_area_t *areas;
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struct async_private_data data;
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kaklik |
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snd_async_handler_t *chandler, *phandler;
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kaklik |
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int count;
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kaklik |
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unsigned int i,j;
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kaklik |
330 |
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527 |
kaklik |
331 |
FILE *out;
|
526 |
kaklik |
332 |
|
527 |
kaklik |
333 |
|
526 |
kaklik |
334 |
snd_pcm_hw_params_alloca(&hwparams);
|
|
|
335 |
snd_pcm_sw_params_alloca(&swparams);
|
|
|
336 |
|
|
|
337 |
//open adn set playback device
|
|
|
338 |
if ((err = snd_pcm_open(&playback_handle, device, SND_PCM_STREAM_PLAYBACK, 0)) < 0) {
|
|
|
339 |
printf("Playback open error: %s\n", snd_strerror(err));
|
|
|
340 |
return 0;
|
|
|
341 |
}
|
|
|
342 |
|
|
|
343 |
if ((err = set_hwparams(playback_handle, hwparams, SND_PCM_ACCESS_RW_INTERLEAVED)) < 0) {
|
|
|
344 |
printf("Setting of hwparams failed: %s\n", snd_strerror(err));
|
|
|
345 |
exit(EXIT_FAILURE);
|
|
|
346 |
}
|
|
|
347 |
if ((err = set_swparams(playback_handle, swparams)) < 0) {
|
|
|
348 |
printf("Setting of swparams failed: %s\n", snd_strerror(err));
|
|
|
349 |
exit(EXIT_FAILURE);
|
|
|
350 |
}
|
|
|
351 |
|
|
|
352 |
//open and set capture device
|
|
|
353 |
if ((err = snd_pcm_open(&capture_handle, device, SND_PCM_STREAM_CAPTURE, 0)) < 0) {
|
|
|
354 |
printf("Playback open error: %s\n", snd_strerror(err));
|
|
|
355 |
return 0;
|
|
|
356 |
}
|
|
|
357 |
|
|
|
358 |
if ((err = set_hwparams(capture_handle, hwparams, SND_PCM_ACCESS_RW_INTERLEAVED)) < 0) {
|
|
|
359 |
printf("Setting of hwparams failed: %s\n", snd_strerror(err));
|
|
|
360 |
exit(EXIT_FAILURE);
|
|
|
361 |
}
|
530 |
kaklik |
362 |
if ((err = set_swparams(capture_handle, swparams)) < 0) {
|
526 |
kaklik |
363 |
printf("Setting of swparams failed: %s\n", snd_strerror(err));
|
|
|
364 |
exit(EXIT_FAILURE);
|
530 |
kaklik |
365 |
}
|
526 |
kaklik |
366 |
|
|
|
367 |
// allocate memory for frame (package of samples)
|
|
|
368 |
frame = malloc((period_size * channels * snd_pcm_format_physical_width(format)) / 8);
|
|
|
369 |
if (frame == NULL) {
|
|
|
370 |
printf("No enough memory\n");
|
|
|
371 |
exit(EXIT_FAILURE);
|
|
|
372 |
}
|
|
|
373 |
|
527 |
kaklik |
374 |
|
|
|
375 |
// dummy structure
|
526 |
kaklik |
376 |
//allocate memory for frame structure definition
|
|
|
377 |
areas = calloc(channels, sizeof(snd_pcm_channel_area_t));
|
|
|
378 |
if (areas == NULL) {
|
|
|
379 |
printf("No enough memory\n");
|
|
|
380 |
exit(EXIT_FAILURE);
|
|
|
381 |
}
|
|
|
382 |
//fill areas by definition of frame structure
|
|
|
383 |
for (chn = 0; chn < channels; chn++) {
|
|
|
384 |
areas[chn].addr = frame; // frame start adress
|
|
|
385 |
areas[chn].first = chn * snd_pcm_format_physical_width(format); // ofset to first sample (in bits)
|
|
|
386 |
areas[chn].step = channels * snd_pcm_format_physical_width(format); // step between samples
|
|
|
387 |
}
|
|
|
388 |
|
527 |
kaklik |
389 |
data.samples = frame;
|
526 |
kaklik |
390 |
data.areas = areas;
|
|
|
391 |
data.period = 1;
|
527 |
kaklik |
392 |
// end of dummy structure
|
526 |
kaklik |
393 |
|
|
|
394 |
|
527 |
kaklik |
395 |
sine(chirp,100000);
|
|
|
396 |
|
|
|
397 |
/// register playback callback
|
|
|
398 |
err = snd_async_add_pcm_handler(&phandler, playback_handle, async_playback_callback, &data); // fill by dummy &data
|
526 |
kaklik |
399 |
if (err < 0) {
|
|
|
400 |
printf("Unable to register async handler\n");
|
|
|
401 |
exit(EXIT_FAILURE);
|
|
|
402 |
}
|
527 |
kaklik |
403 |
for (period = 0; period < 3; period++) {
|
526 |
kaklik |
404 |
|
527 |
kaklik |
405 |
err = snd_pcm_writei(playback_handle, (chirp+period*period_size), period_size);
|
526 |
kaklik |
406 |
if (err < 0) {
|
|
|
407 |
printf("Initial write error: %s\n", snd_strerror(err));
|
|
|
408 |
exit(EXIT_FAILURE);
|
|
|
409 |
}
|
|
|
410 |
if (err != period_size) {
|
|
|
411 |
printf("Initial write error: written %i expected %li\n", err, period_size);
|
|
|
412 |
exit(EXIT_FAILURE);
|
|
|
413 |
}
|
|
|
414 |
}
|
|
|
415 |
|
527 |
kaklik |
416 |
// register capture callback
|
|
|
417 |
err = snd_async_add_pcm_handler(&chandler, capture_handle, async_capture_callback, &data); // fill by dummy &data
|
|
|
418 |
if (err < 0) {
|
|
|
419 |
printf("Unable to register async handler\n");
|
|
|
420 |
exit(EXIT_FAILURE);
|
|
|
421 |
}
|
|
|
422 |
|
526 |
kaklik |
423 |
//start playback
|
|
|
424 |
if (snd_pcm_state(playback_handle) == SND_PCM_STATE_PREPARED) {
|
|
|
425 |
err = snd_pcm_start(playback_handle);
|
|
|
426 |
if (err < 0) {
|
|
|
427 |
printf("Start error: %s\n", snd_strerror(err));
|
|
|
428 |
exit(EXIT_FAILURE);
|
|
|
429 |
}
|
|
|
430 |
}
|
|
|
431 |
|
527 |
kaklik |
432 |
//start capture
|
|
|
433 |
if ((err = snd_pcm_prepare (capture_handle)) < 0) {
|
|
|
434 |
fprintf (stderr, "cannot prepare audio interface for use (%s)\n",
|
|
|
435 |
snd_strerror (err));
|
|
|
436 |
exit (1);
|
|
|
437 |
}
|
|
|
438 |
|
|
|
439 |
err = snd_pcm_start(capture_handle);
|
|
|
440 |
if (err < 0) {
|
|
|
441 |
printf("Start error: %s\n", snd_strerror(err));
|
|
|
442 |
exit(EXIT_FAILURE);
|
|
|
443 |
}
|
|
|
444 |
|
|
|
445 |
|
|
|
446 |
|
526 |
kaklik |
447 |
/* because all other work is done in the signal handler,
|
|
|
448 |
suspend the process */
|
530 |
kaklik |
449 |
while(cperiod<3) {
|
526 |
kaklik |
450 |
sleep(1);
|
527 |
kaklik |
451 |
}
|
526 |
kaklik |
452 |
|
527 |
kaklik |
453 |
out=fopen("./output.txt","w");
|
|
|
454 |
for(i=0;i<=100000;i++) fprintf(out,"%d ",signal[i]);
|
|
|
455 |
fclose(out);
|
526 |
kaklik |
456 |
|
|
|
457 |
free(areas);
|
|
|
458 |
free(frame);
|
527 |
kaklik |
459 |
|
526 |
kaklik |
460 |
snd_pcm_close(playback_handle);
|
|
|
461 |
snd_pcm_close(capture_handle);
|
|
|
462 |
return 0;
|
|
|
463 |
}
|
|
|
464 |
|