SPAN_DECLARE(fax_modems_state_t *) fax_modems_init(fax_modems_state_t *s,
int use_tep,
hdlc_frame_handler_t hdlc_accept,
hdlc_underflow_handler_t hdlc_tx_underflow,
put_bit_func_t non_ecm_put_bit,
get_bit_func_t non_ecm_get_bit,
tone_report_func_t tone_callback,
void *user_data)
{
if (s == NULL)
{
if ((s = (fax_modems_state_t *) span_alloc(sizeof(*s))) == NULL)
return NULL;
}
/*endif*/
memset(s, 0, sizeof(*s));
s->use_tep = use_tep;
modem_connect_tones_tx_init(&s->connect_tx, MODEM_CONNECT_TONES_FAX_CNG);
span_log_init(&s->logging, SPAN_LOG_NONE, NULL);
span_log_set_protocol(&s->logging, "FAX modems");
s->tone_callback = tone_callback;
s->tone_callback_user_data = user_data;
if (tone_callback)
{
modem_connect_tones_rx_init(&s->connect_rx,
MODEM_CONNECT_TONES_FAX_CNG,
s->tone_callback,
s->tone_callback_user_data);
}
/*endif*/
dc_restore_init(&s->dc_restore);
s->get_bit = non_ecm_get_bit;
s->get_bit_user_data = user_data;
s->put_bit = non_ecm_put_bit;
s->put_bit_user_data = user_data;
s->hdlc_accept = hdlc_accept;
s->hdlc_accept_user_data = user_data;
hdlc_rx_init(&s->hdlc_rx, false, false, HDLC_FRAMING_OK_THRESHOLD, fax_modems_hdlc_accept, s);
hdlc_tx_init(&s->hdlc_tx, false, 2, false, hdlc_tx_underflow, user_data);
fax_modems_start_slow_modem(s, FAX_MODEM_V21_RX);
fsk_tx_init(&s->v21_tx, &preset_fsk_specs[FSK_V21CH2], (get_bit_func_t) hdlc_tx_get_bit, &s->hdlc_tx);
silence_gen_init(&s->silence_gen, 0);
s->rx_signal_present = false;
s->rx_handler = (span_rx_handler_t) &span_dummy_rx;
s->rx_fillin_handler = (span_rx_fillin_handler_t) &span_dummy_rx;
s->rx_user_data = NULL;
s->rx_fillin_user_data = NULL;
s->tx_handler = (span_tx_handler_t) &silence_gen;
s->tx_user_data = &s->silence_gen;
return s;
}
int main (int argc, char *argv[])
{
awgn_state_t noise_source;
dc_restore_state_t dc_state;
int i;
int idum = 1234567;
int16_t dirty;
int16_t clean;
int estimate;
int min;
int max;
int dc_offset;
dc_offset = 5000;
awgn_init_dbm0(&noise_source, idum, -10.0);
dc_restore_init(&dc_state);
for (i = 0; i < 100000; i++)
{
dirty = awgn(&noise_source) + dc_offset;
clean = dc_restore(&dc_state, dirty);
if ((i % 1000) == 0)
{
printf("Sample %6d: %d (expect %d)\n",
i,
dc_restore_estimate(&dc_state),
dc_offset);
}
}
/* We should have settled by now. Look at the variation we get */
min = 99999;
max = -99999;
for (i = 0; i < 100000; i++)
{
dirty = awgn(&noise_source) + dc_offset;
clean = dc_restore(&dc_state, dirty);
estimate = dc_restore_estimate(&dc_state);
if (estimate < min)
min = estimate;
if (estimate > max)
max = estimate;
}
printf("Spread of DC estimate for an offset of %d was %d to %d\n", dc_offset, min, max);
if (min < dc_offset - 50 || max > dc_offset + 50)
{
printf("Test failed.\n");
exit(2);
}
printf("Test passed.\n");
return 0;
}
SPAN_DECLARE(fax_modems_state_t *) fax_modems_init(fax_modems_state_t *s,
int use_tep,
hdlc_frame_handler_t hdlc_accept,
hdlc_underflow_handler_t hdlc_tx_underflow,
put_bit_func_t non_ecm_put_bit,
get_bit_func_t non_ecm_get_bit,
tone_report_func_t tone_callback,
void *user_data)
{
if (s == NULL)
{
if ((s = (fax_modems_state_t *) malloc(sizeof(*s))) == NULL)
return NULL;
}
memset(s, 0, sizeof(*s));
s->use_tep = use_tep;
hdlc_rx_init(&s->hdlc_rx, FALSE, FALSE, HDLC_FRAMING_OK_THRESHOLD, hdlc_accept, user_data);
hdlc_tx_init(&s->hdlc_tx, FALSE, 2, FALSE, hdlc_tx_underflow, user_data);
fsk_rx_init(&s->v21_rx, &preset_fsk_specs[FSK_V21CH2], TRUE, (put_bit_func_t) hdlc_rx_put_bit, &s->hdlc_rx);
fsk_rx_signal_cutoff(&s->v21_rx, -39.09f);
fsk_tx_init(&s->v21_tx, &preset_fsk_specs[FSK_V21CH2], (get_bit_func_t) hdlc_tx_get_bit, &s->hdlc_tx);
v17_rx_init(&s->v17_rx, 14400, non_ecm_put_bit, user_data);
v17_tx_init(&s->v17_tx, 14400, s->use_tep, non_ecm_get_bit, user_data);
v29_rx_init(&s->v29_rx, 9600, non_ecm_put_bit, user_data);
v29_rx_signal_cutoff(&s->v29_rx, -45.5f);
v29_tx_init(&s->v29_tx, 9600, s->use_tep, non_ecm_get_bit, user_data);
v27ter_rx_init(&s->v27ter_rx, 4800, non_ecm_put_bit, user_data);
v27ter_tx_init(&s->v27ter_tx, 4800, s->use_tep, non_ecm_get_bit, user_data);
silence_gen_init(&s->silence_gen, 0);
modem_connect_tones_tx_init(&s->connect_tx, MODEM_CONNECT_TONES_FAX_CNG);
if (tone_callback)
{
modem_connect_tones_rx_init(&s->connect_rx,
MODEM_CONNECT_TONES_FAX_CNG,
tone_callback,
user_data);
}
dc_restore_init(&s->dc_restore);
s->rx_signal_present = FALSE;
s->rx_handler = (span_rx_handler_t *) &span_dummy_rx;
s->rx_user_data = NULL;
s->tx_handler = (span_tx_handler_t *) &silence_gen;
s->tx_user_data = &s->silence_gen;
return s;
}
fax_state_t *fax_init(fax_state_t *s, int calling_party)
{
if (s == NULL)
{
if ((s = (fax_state_t *) malloc(sizeof(*s))) == NULL)
return NULL;
}
memset(s, 0, sizeof(*s));
span_log_init(&s->logging, SPAN_LOG_NONE, NULL);
span_log_set_protocol(&s->logging, "FAX");
t30_init(&(s->t30_state),
calling_party,
fax_set_rx_type,
(void *) s,
fax_set_tx_type,
(void *) s,
fax_send_hdlc,
(void *) s);
t30_set_supported_modems(&(s->t30_state),
T30_SUPPORT_V27TER | T30_SUPPORT_V29);
hdlc_rx_init(&(s->hdlcrx), FALSE, FALSE, 5, t30_hdlc_accept, &(s->t30_state));
fsk_rx_init(&(s->v21rx), &preset_fsk_specs[FSK_V21CH2], TRUE, (put_bit_func_t) hdlc_rx_put_bit, &(s->hdlcrx));
fsk_rx_signal_cutoff(&(s->v21rx), -45.5);
hdlc_tx_init(&(s->hdlctx), FALSE, 2, FALSE, hdlc_underflow_handler, &(s->t30_state));
s->first_tx_hdlc_frame = TRUE;
fsk_tx_init(&(s->v21tx), &preset_fsk_specs[FSK_V21CH2], (get_bit_func_t) hdlc_tx_get_bit, &(s->hdlctx));
v17_rx_init(&(s->v17rx), 14400, t30_non_ecm_put_bit, &(s->t30_state));
v17_tx_init(&(s->v17tx), 14400, s->use_tep, t30_non_ecm_get_bit, &(s->t30_state));
v29_rx_init(&(s->v29rx), 9600, t30_non_ecm_put_bit, &(s->t30_state));
v29_rx_signal_cutoff(&(s->v29rx), -45.5);
v29_tx_init(&(s->v29tx), 9600, s->use_tep, t30_non_ecm_get_bit, &(s->t30_state));
v27ter_rx_init(&(s->v27ter_rx), 4800, t30_non_ecm_put_bit, &(s->t30_state));
v27ter_tx_init(&(s->v27ter_tx), 4800, s->use_tep, t30_non_ecm_get_bit, &(s->t30_state));
silence_gen_init(&(s->silence_gen), 0);
dc_restore_init(&(s->dc_restore));
t30_restart(&(s->t30_state));
#if defined(LOG_FAX_AUDIO)
{
char buf[100 + 1];
struct tm *tm;
time_t now;
time(&now);
tm = localtime(&now);
sprintf(buf,
"/tmp/fax-rx-audio-%x-%02d%02d%02d%02d%02d%02d",
s,
tm->tm_year%100,
tm->tm_mon + 1,
tm->tm_mday,
tm->tm_hour,
tm->tm_min,
tm->tm_sec);
s->fax_audio_rx_log = open(buf, O_CREAT | O_TRUNC | O_WRONLY, 0666);
sprintf(buf,
"/tmp/fax-tx-audio-%x-%02d%02d%02d%02d%02d%02d",
s,
tm->tm_year%100,
tm->tm_mon + 1,
tm->tm_mday,
tm->tm_hour,
tm->tm_min,
tm->tm_sec);
s->fax_audio_tx_log = open(buf, O_CREAT | O_TRUNC | O_WRONLY, 0666);
}
#endif
return s;
}