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Updated SpanDSP to snapshot on 2009-06-03 with some additions:

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Fixed VS2005 version of make_modem_filter

  Fixed a couple of places where declaration and definition of functions do not have the same calling conventions. Only relevant for Win32 compiles.


git-svn-id: http://svn.freeswitch.org/svn/freeswitch/trunk@13831 d0543943-73ff-0310-b7d9-9358b9ac24b2
This commit is contained in:
Robert Joly committed 2009-06-18 06:13:59 +00:00
1 parent 832bab2a4a
commit e791f33545
131 files changed
+8988 -2017
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libs/spandsp/src/v17rx.c
+83 -86
View File
@@ -23,7 +23,7 @@
* License along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*
* $Id: v17rx.c,v 1.146 2009/04/21 13:59:07 steveu Exp $
* $Id: v17rx.c,v 1.149 2009/06/02 16:03:56 steveu Exp $
*/
/*! \file */
@@ -64,12 +64,12 @@
#include "spandsp/private/logging.h"
#include "spandsp/private/v17rx.h"
#include "v17tx_constellation_maps.h"
#include "v17rx_constellation_maps.h"
#include "v17_v32bis_tx_constellation_maps.h"
#include "v17_v32bis_rx_constellation_maps.h"
#if defined(SPANDSP_USE_FIXED_POINT)
#include "v17rx_fixed_rrc.h"
#include "v17_v32bis_rx_fixed_rrc.h"
#else
#include "v17rx_floating_rrc.h"
#include "v17_v32bis_rx_floating_rrc.h"
#endif
/*! The nominal frequency of the carrier, in Hertz */
@@ -295,18 +295,6 @@ static int descramble(v17_rx_state_t *s, int in_bit)
}
/*- End of function --------------------------------------------------------*/
static __inline__ int find_quadrant(complexf_t *z)
{
int b1;
int b2;
/* Split the space along the two diagonals. */
b1 = (z->im > z->re);
b2 = (z->im < -z->re);
return (b2 << 1) | (b1 ^ b2);
}
/*- End of function --------------------------------------------------------*/
static void track_carrier(v17_rx_state_t *s, const complexf_t *z, const complexf_t *target)
{
float error;
@@ -1008,12 +996,81 @@ static void process_half_baud(v17_rx_state_t *s, const complexf_t *sample)
}
/*- End of function --------------------------------------------------------*/
static __inline__ int signal_detect(v17_rx_state_t *s, int16_t amp)
{
int16_t diff;
int16_t x;
int32_t power;
/* There should be no DC in the signal, but sometimes there is.
We need to measure the power with the DC blocked, but not using
a slow to respond DC blocker. Use the most elementary HPF. */
x = amp >> 1;
/* There could be overflow here, but it isn't a problem in practice */
diff = x - s->last_sample;
s->last_sample = x;
power = power_meter_update(&(s->power), diff);
#if defined(IAXMODEM_STUFF)
/* Quick power drop fudge */
diff = abs(diff);
if (10*diff < s->high_sample)
{
if (++s->low_samples > 120)
{
power_meter_init(&(s->power), 4);
s->high_sample = 0;
s->low_samples = 0;
}
}
else
{
s->low_samples = 0;
if (diff > s->high_sample)
s->high_sample = diff;
}
#endif
if (s->signal_present > 0)
{
/* Look for power below turn-off threshold to turn the carrier off */
#if defined(IAXMODEM_STUFF)
if (s->carrier_drop_pending || power < s->carrier_off_power)
#else
if (power < s->carrier_off_power)
#endif
{
if (--s->signal_present <= 0)
{
/* Count down a short delay, to ensure we push the last
few bits through the filters before stopping. */
v17_rx_restart(s, s->bit_rate, s->short_train);
report_status_change(s, SIG_STATUS_CARRIER_DOWN);
return 0;
}
#if defined(IAXMODEM_STUFF)
/* Carrier has dropped, but the put_bit is pending the signal_present delay. */
s->carrier_drop_pending = TRUE;
#endif
}
}
else
{
/* Look for power exceeding turn-on threshold to turn the carrier on */
if (power < s->carrier_on_power)
return 0;
s->signal_present = 1;
#if defined(IAXMODEM_STUFF)
s->carrier_drop_pending = FALSE;
#endif
report_status_change(s, SIG_STATUS_CARRIER_UP);
}
return power;
}
/*- End of function --------------------------------------------------------*/
SPAN_DECLARE_NONSTD(int) v17_rx(v17_rx_state_t *s, const int16_t amp[], int len)
{
int i;
int step;
int16_t x;
int16_t diff;
complexf_t z;
complexf_t zz;
complexf_t sample;
@@ -1033,68 +1090,8 @@ SPAN_DECLARE_NONSTD(int) v17_rx(v17_rx_state_t *s, const int16_t amp[], int len)
if (++s->rrc_filter_step >= V17_RX_FILTER_STEPS)
s->rrc_filter_step = 0;
/* There should be no DC in the signal, but sometimes there is.
We need to measure the power with the DC blocked, but not using
a slow to respond DC blocker. Use the most elementary HPF. */
x = amp[i] >> 1;
/* There could be overflow here, but it isn't a problem in practice */
diff = x - s->last_sample;
power = power_meter_update(&(s->power), diff);
#if defined(IAXMODEM_STUFF)
/* Quick power drop fudge */
diff = abs(diff);
if (10*diff < s->high_sample)
{
if (++s->low_samples > 120)
{
power_meter_init(&(s->power), 4);
s->high_sample = 0;
s->low_samples = 0;
}
}
else
{
s->low_samples = 0;
if (diff > s->high_sample)
s->high_sample = diff;
}
#endif
s->last_sample = x;
if (s->signal_present)
{
/* Look for power below turnoff threshold to turn the carrier off */
#if defined(IAXMODEM_STUFF)
if (s->carrier_drop_pending || power < s->carrier_off_power)
#else
if (power < s->carrier_off_power)
#endif
{
if (--s->signal_present <= 0)
{
/* Count down a short delay, to ensure we push the last
few bits through the filters before stopping. */
v17_rx_restart(s, s->bit_rate, s->short_train);
report_status_change(s, SIG_STATUS_CARRIER_DOWN);
continue;
}
#if defined(IAXMODEM_STUFF)
/* Carrier has dropped, but the put_bit is
pending the signal_present delay. */
s->carrier_drop_pending = TRUE;
#endif
}
}
else
{
/* Look for power exceeding turnon threshold to turn the carrier on */
if (power < s->carrier_on_power)
continue;
s->signal_present = 1;
#if defined(IAXMODEM_STUFF)
s->carrier_drop_pending = FALSE;
#endif
report_status_change(s, SIG_STATUS_CARRIER_UP);
}
if ((power = signal_detect(s, amp[i])) == 0)
continue;
if (s->training_stage == TRAINING_STAGE_PARKED)
continue;
/* Only spend effort processing this data if the modem is not
@@ -1171,7 +1168,7 @@ SPAN_DECLARE(int) v17_rx_fillin(v17_rx_state_t *s, int len)
/* We want to sustain the current state (i.e carrier on<->carrier off), and
try to sustain the carrier phase. We should probably push the filters, as well */
span_log(&s->logging, SPAN_LOG_FLOW, "Fill-in %d samples\n", len);
if (!s->signal_present)
if (s->signal_present <= 0)
return 0;
if (s->training_stage == TRAINING_STAGE_PARKED)
return 0;
@@ -1220,22 +1217,22 @@ SPAN_DECLARE(int) v17_rx_restart(v17_rx_state_t *s, int bit_rate, int short_trai
switch (bit_rate)
{
case 14400:
s->constellation = v17_14400_constellation;
s->constellation = v17_v32bis_14400_constellation;
s->space_map = 0;
s->bits_per_symbol = 6;
break;
case 12000:
s->constellation = v17_12000_constellation;
s->constellation = v17_v32bis_12000_constellation;
s->space_map = 1;
s->bits_per_symbol = 5;
break;
case 9600:
s->constellation = v17_9600_constellation;
s->constellation = v17_v32bis_9600_constellation;
s->space_map = 2;
s->bits_per_symbol = 4;
break;
case 7200:
s->constellation = v17_7200_constellation;
s->constellation = v17_v32bis_7200_constellation;
s->space_map = 3;
s->bits_per_symbol = 3;
break;