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Neu structure for the paging process (B-Netz)

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Paging tones are not created within sound_alsa.c
The audio API is now responsible to switch to paging channel.
In case of SDR, the sdr.c will switch frequency offset.
This commit is contained in:
Andreas Eversberg
2017-01-07 10:33:13 +01:00
parent 57993e3e48
commit 8b9277615d
15 changed files with 238 additions and 197 deletions
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65
src/common/sound_alsa.c
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@@ -21,11 +21,13 @@
#include <stdint.h>
#include <alsa/asoundlib.h>
#include "debug.h"
#include "sound.h"
#include "sender.h"
typedef struct sound {
snd_pcm_t *phandle, *chandle;
int pchannels, cchannels;
double paging_phaseshift; /* phase to shift every sample */
double paging_phase; /* current phase */
} sound_t;
static int set_hw_params(snd_pcm_t *handle, int samplerate, int *channels)
@@ -128,7 +130,7 @@ static int sound_prepare(sound_t *sound)
return 0;
}
void *sound_open(const char *audiodev, double __attribute__((unused)) *tx_frequency, double __attribute__((unused)) *rx_frequency, int channels, int samplerate, double __attribute__((unused)) bandwidth, double __attribute__((unused)) sample_deviation)
void *sound_open(const char *audiodev, double __attribute__((unused)) *tx_frequency, double __attribute__((unused)) *rx_frequency, int channels, double __attribute__((unused)) paging_frequency, int samplerate, double __attribute__((unused)) bandwidth, double __attribute__((unused)) sample_deviation)
{
sound_t *sound;
int rc;
@@ -144,6 +146,8 @@ void *sound_open(const char *audiodev, double __attribute__((unused)) *tx_freque
return NULL;
}
sound->paging_phaseshift = 1.0 / ((double)samplerate / 1000.0);
rc = snd_pcm_open(&sound->phandle, audiodev, SND_PCM_STREAM_PLAYBACK, SND_PCM_NONBLOCK);
if (rc < 0) {
PDEBUG(DSOUND, DEBUG_ERROR, "Failed to open '%s' for playback! (%s)\n", audiodev, snd_strerror(rc));
@@ -200,7 +204,51 @@ void sound_close(void *inst)
free(sound);
}
int sound_write(void *inst, int16_t **samples, int num, int channels)
static void gen_paging_tone(sound_t *sound, int16_t *samples, int length, enum paging_signal paging_signal, int on)
{
double phaseshift, phase;
int i;
switch (paging_signal) {
case PAGING_SIGNAL_NOTONE:
/* no tone if paging signal is on */
on = !on;
// fall through
case PAGING_SIGNAL_TONE:
/* tone if paging signal is on */
if (on) {
phaseshift = sound->paging_phaseshift;
phase = sound->paging_phase;
for (i = 0; i < length; i++) {
if (phase < 0.5)
*samples++ = 30000;
else
*samples++ = -30000;
phase += phaseshift;
if (phase >= 1.0)
phase -= 1.0;
}
sound->paging_phase = phase;
} else
memset(samples, 0, length << 1);
break;
case PAGING_SIGNAL_NEGATIVE:
/* negative signal if paging signal is on */
on = !on;
// fall through
case PAGING_SIGNAL_POSITIVE:
/* positive signal if paging signal is on */
if (on)
memset(samples, 127, length << 1);
else
memset(samples, 128, length << 1);
break;
case PAGING_SIGNAL_NONE:
break;
}
}
int sound_write(void *inst, int16_t **samples, int num, enum paging_signal *paging_signal, int *on, int channels)
{
sound_t *sound = (sound_t *)inst;
int16_t buff[num << 1];
@@ -208,15 +256,22 @@ int sound_write(void *inst, int16_t **samples, int num, int channels)
int i, ii;
if (sound->pchannels == 2) {
if (channels < 2) {
if (paging_signal && on && paging_signal[0] != PAGING_SIGNAL_NONE) {
int16_t paging[num << 1];
gen_paging_tone(sound, paging, num, paging_signal[0], on[0]);
for (i = 0, ii = 0; i < num; i++) {
buff[ii++] = samples[0][i];
buff[ii++] = paging[i];
}
} else if (channels == 2) {
for (i = 0, ii = 0; i < num; i++) {
buff[ii++] = samples[0][i];
buff[ii++] = samples[1][i];
}
} else {
for (i = 0, ii = 0; i < num; i++) {
buff[ii++] = samples[0][i];
buff[ii++] = samples[1][i];
buff[ii++] = samples[0][i];
}
}
rc = snd_pcm_writei(sound->phandle, buff, num);