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#undef NDEBUG
#include <stdio.h>
#include <assert.h>
#include <inttypes.h>
#include <stdbool.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/time.h>
#include <spandsp/telephony.h>
#include <spandsp/logging.h>
#include <spandsp/t38_core.h>
#include <spandsp/t30.h>
#include <spandsp/t30_api.h>
#include <spandsp/fax.h>
#include "compat.h"
#include "spandsp_logging.h"
#define SAMPLES_PER_CHUNK 160
#define MICROSECONDS_PER_CHUNK 20000
#ifndef FALSE
# define FALSE false
#endif
// from ITU G.191
void alaw_compress (size_t lseg, int16_t *linbuf, uint8_t *logbuf) {
short ix, iexp;
long n;
for (n = 0; n < lseg; n++) {
ix = linbuf[n] < 0 /* 0 <= ix < 2048 */
? (~linbuf[n]) >> 4 /* 1's complement for negative values */
: (linbuf[n]) >> 4;
/* Do more, if exponent > 0 */
if (ix > 15) { /* exponent=0 for ix <= 15 */
iexp = 1; /* first step: */
while (ix > 16 + 15) { /* find mantissa and exponent */
ix >>= 1;
iexp++;
}
ix -= 16; /* second step: remove leading '1' */
ix += iexp << 4; /* now compute encoded value */
}
if (linbuf[n] >= 0)
ix |= (0x0080); /* add sign bit */
logbuf[n] = ix ^ (0x0055); /* toggle even bits */
}
}
void alaw_expand (size_t lseg, uint8_t *logbuf, int16_t *linbuf) {
short ix, mant, iexp;
long n;
for (n = 0; n < lseg; n++) {
ix = logbuf[n] ^ (0x0055); /* re-toggle toggled bits */
ix &= (0x007F); /* remove sign bit */
iexp = ix >> 4; /* extract exponent */
mant = ix & (0x000F); /* now get mantissa */
if (iexp > 0)
mant = mant + 16; /* add leading '1', if exponent > 0 */
mant = (mant << 4) + (0x0008); /* now mantissa left justified and */
/* 1/2 quantization step added */
if (iexp > 1) /* now left shift according exponent */
mant = mant << (iexp - 1);
linbuf[n] = logbuf[n] > 127 /* invert, if negative sample */
? mant : -mant;
}
}
int done = 0;
static void phase_e_handler(PHASE_E_HANDLER_ARGS) {
fprintf(stderr, "recv: phase E result %i\n", result);
assert(result == T30_ERR_OK);
done = 1;
}
int main(int argc, char **argv) {
assert(argc == 2);
const char *output_file_name = argv[1];
fax_state_t *fax = fax_init(NULL, FALSE);
assert(fax != NULL);
int use_transmit_on_idle = 1;
int use_tep = 0;
int supported_modems = T30_SUPPORT_V27TER | T30_SUPPORT_V29 | T30_SUPPORT_V17;
int use_ecm = 0;
// taken from t38_gateway_tests.c
t30_state_t *t30 = fax_get_t30_state(fax);
fax_set_transmit_on_idle(fax, use_transmit_on_idle);
fax_set_tep_mode(fax, use_tep);
t30_set_supported_modems(t30, supported_modems);
t30_set_tx_ident(t30, "11111111");
t30_set_tx_nsf(t30, (const uint8_t *) "\x50\x00\x00\x00Spandsp\x00", 12);
t30_set_rx_file(t30, output_file_name, -1);
t30_set_phase_e_handler(t30, phase_e_handler, NULL);
t30_set_ecm_capability(t30, use_ecm);
// if (use_ecm)
// t30_set_supported_compressions(t30, T30_SUPPORT_T4_1D_COMPRESSION | T30_SUPPORT_T4_2D_COMPRESSION | T30_SUPPORT_T6_COMPRESSION);
t30_set_minimum_scan_line_time(t30, 40);
struct timeval now, next;
setbuf(stdout, NULL);
gettimeofday(&now, NULL);
while (!done) {
next = now;
next.tv_usec += MICROSECONDS_PER_CHUNK;
while (next.tv_usec >= 1000000) {
next.tv_usec -= 1000000;
next.tv_sec++;
}
int16_t samples[SAMPLES_PER_CHUNK];
int ret = fax_tx(fax, samples, SAMPLES_PER_CHUNK);
assert(ret == SAMPLES_PER_CHUNK);
uint8_t alaw[SAMPLES_PER_CHUNK];
alaw_compress(SAMPLES_PER_CHUNK, samples, alaw);
ret = fwrite(alaw, SAMPLES_PER_CHUNK, 1, stdout);
assert(ret == 1);
ret = fread(alaw, SAMPLES_PER_CHUNK, 1, stdin);
assert(ret == 1);
alaw_expand(SAMPLES_PER_CHUNK, alaw, samples);
ret = fax_rx(fax, samples, SAMPLES_PER_CHUNK);
assert(ret == 0);
while (1) {
gettimeofday(&now, NULL);
long long diff = ((long long) next.tv_sec - now.tv_sec) * 1000000
+ ((long long) next.tv_usec - now.tv_usec);
if (diff <= 0)
break;
usleep(diff);
}
}
return 0;
}
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