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Meshtastic-Apple/Meshtastic/Audio/codec2-ios/freedv_api.c
Benjamin Faershtein 90aecb4d08 working changes
2026-02-23 15:20:08 -08:00

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/*---------------------------------------------------------------------------*\
FILE........: freedv_api.c
AUTHOR......: David Rowe
DATE CREATED: August 2014
Library of API functions that implement FreeDV "modes", useful for
embedding FreeDV in other programs.
\*---------------------------------------------------------------------------*/
/*
Copyright (C) 2014 David Rowe
All rights reserved.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License version 2.1, as
published by the Free Software Foundation. This program is
distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
License for more details.
You should have received a copy of the GNU Lesser General Public License
along with this program; if not, see <http://www.gnu.org/licenses/>.
*/
#include <assert.h>
#include <stdlib.h>
#include <stdint.h>
#include <stdio.h>
#include <string.h>
#include <math.h>
#include "fsk.h"
#include "fmfsk.h"
#include "codec2.h"
#include "codec2_fdmdv.h"
#include "fdmdv_internal.h"
#include "golay23.h"
#include "varicode.h"
#include "freedv_api.h"
#include "freedv_api_internal.h"
#include "freedv_vhf_framing.h"
#include "comp_prim.h"
#define VERSION 11 /* The API version number. The first version
is 10. Increment if the API changes in a
way that would require changes by the API
user. */
/*
* Version 10 Initial version August 2, 2015.
* Version 11 September 2015
* Added: freedv_zero_total_bit_errors(), freedv_get_sync()
* Changed all input and output sample rates to 8000 sps. Rates for FREEDV_MODE_700 and 700B were 7500.
*/
#define NORM_PWR 1.74 /* experimentally derived fudge factor so 1600 and
700 mode have the same tx power */
/*---------------------------------------------------------------------------*\
FUNCTION....: freedv_open
AUTHOR......: David Rowe
DATE CREATED: 3 August 2014
Call this first to initialise. Returns NULL if initialisation fails
(e.g. out of memory or mode not supported).
\*---------------------------------------------------------------------------*/
struct freedv *freedv_open(int mode) {
struct freedv *f;
int Nc, codec2_mode, nbit, nbyte;
if ((mode != FREEDV_MODE_1600) && (mode != FREEDV_MODE_700) &&
(mode != FREEDV_MODE_700B) && (mode != FREEDV_MODE_2400A) &&
(mode != FREEDV_MODE_2400B) && (mode != FREEDV_MODE_800XA))
return NULL;
f = (struct freedv*)malloc(sizeof(struct freedv));
if (f == NULL)
return NULL;
f->mode = mode;
f->test_frames = f->smooth_symbols = 0;
f->freedv_put_error_pattern = NULL;
f->error_pattern_callback_state = NULL;
f->n_protocol_bits = 0;
if (mode == FREEDV_MODE_1600) {
f->snr_squelch_thresh = 2.0;
f->squelch_en = 1;
Nc = 16;
f->tx_sync_bit = 0;
codec2_mode = CODEC2_MODE_1300;
f->fdmdv = fdmdv_create(Nc);
if (f->fdmdv == NULL)
return NULL;
golay23_init();
f->nin = FDMDV_NOM_SAMPLES_PER_FRAME;
f->n_nom_modem_samples = 2*FDMDV_NOM_SAMPLES_PER_FRAME;
f->n_nat_modem_samples = f->n_nom_modem_samples;
f->n_max_modem_samples = FDMDV_NOM_SAMPLES_PER_FRAME+FDMDV_MAX_SAMPLES_PER_FRAME;
f->modem_sample_rate = FS;
nbit = fdmdv_bits_per_frame(f->fdmdv);
f->fdmdv_bits = (int*)malloc(nbit*sizeof(int));
if (f->fdmdv_bits == NULL)
return NULL;
nbit = 2*fdmdv_bits_per_frame(f->fdmdv);
f->tx_bits = (int*)malloc(nbit*sizeof(int));
f->rx_bits = (int*)malloc(nbit*sizeof(int));
if ((f->tx_bits == NULL) || (f->rx_bits == NULL))
return NULL;
f->evenframe = 0;
f->sz_error_pattern = fdmdv_error_pattern_size(f->fdmdv);
}
#ifndef CORTEX_M4
if ((mode == FREEDV_MODE_700) || (mode == FREEDV_MODE_700B)) {
f->snr_squelch_thresh = 0.0;
f->squelch_en = 0;
if (mode == FREEDV_MODE_700)
codec2_mode = CODEC2_MODE_700;
else
codec2_mode = CODEC2_MODE_700B;
f->cohpsk = cohpsk_create();
f->nin = COHPSK_NOM_SAMPLES_PER_FRAME;
f->n_nat_modem_samples = COHPSK_NOM_SAMPLES_PER_FRAME; // native modem samples as used by the modem
f->n_nom_modem_samples = f->n_nat_modem_samples * 8000 / 7500; // number of samples after native samples are interpolated to 8000 sps
f->n_max_modem_samples = COHPSK_MAX_SAMPLES_PER_FRAME * 8000 / 7500 + 1;
f->modem_sample_rate = COHPSK_FS; /* note wierd sample rate */
f->clip = 1;
nbit = COHPSK_BITS_PER_FRAME;
f->tx_bits = (int*)malloc(nbit*sizeof(int));
if (f->tx_bits == NULL)
return NULL;
f->sz_error_pattern = cohpsk_error_pattern_size();
}
if ((mode == FREEDV_MODE_2400A) || (mode == FREEDV_MODE_2400B)){
/* Set up the C2 mode */
codec2_mode = CODEC2_MODE_1300;
/* Set the number of protocol bits */
f->n_protocol_bits = 20;
}
if (mode == FREEDV_MODE_2400A) {
/* Create the framer|deframer */
f->deframer = fvhff_create_deframer(FREEDV_VHF_FRAME_A,0);
if(f->deframer == NULL)
return NULL;
f->fsk = fsk_create_hbr(48000,1200,10,4,1200,1200);
/* Note: fsk expects tx/rx bits as an array of uint8_ts, not ints */
f->tx_bits = (int*)malloc(f->fsk->Nbits*sizeof(uint8_t));
if(f->fsk == NULL){
fvhff_destroy_deframer(f->deframer);
return NULL;
}
f->n_nom_modem_samples = f->fsk->N;
f->n_max_modem_samples = f->fsk->N + (f->fsk->Ts);
f->n_nat_modem_samples = f->fsk->N;
f->nin = fsk_nin(f->fsk);
f->modem_sample_rate = 48000;
/* Malloc something to appease freedv_init and freedv_destroy */
f->codec_bits = malloc(1);
/* Set up the stats */
fsk_setup_modem_stats(f->fsk,&(f->stats));
}
if (mode == FREEDV_MODE_2400B) {
/* Create the framer|deframer */
f->deframer = fvhff_create_deframer(FREEDV_VHF_FRAME_A,1);
if(f->deframer == NULL)
return NULL;
f->fmfsk = fmfsk_create(48000,2400);
if(f->fmfsk == NULL){
fvhff_destroy_deframer(f->deframer);
return NULL;
}
/* Note: fsk expects tx/rx bits as an array of uint8_ts, not ints */
f->tx_bits = (int*)malloc(f->fmfsk->nbit*sizeof(uint8_t));
f->n_nom_modem_samples = f->fmfsk->N;
f->n_max_modem_samples = f->fmfsk->N + (f->fmfsk->Ts);
f->n_nat_modem_samples = f->fmfsk->N;
f->nin = fmfsk_nin(f->fmfsk);
f->modem_sample_rate = 48000;
/* Malloc something to appease freedv_init and freedv_destroy */
f->codec_bits = malloc(1);
/* Set up the stats */
fmfsk_setup_modem_stats(f->fmfsk,&(f->stats));
}
if (mode == FREEDV_MODE_800XA) {
/* Create the framer|deframer */
f->deframer = fvhff_create_deframer(FREEDV_HF_FRAME_B,0);
if(f->deframer == NULL)
return NULL;
f->fsk = fsk_create_hbr(8000,400,10,4,400,400);
fsk_set_nsym(f->fsk,32);
/* Note: fsk expects tx/rx bits as an array of uint8_ts, not ints */
f->tx_bits = (int*)malloc(f->fsk->Nbits*sizeof(uint8_t));
if(f->fsk == NULL){
fvhff_destroy_deframer(f->deframer);
return NULL;
}
f->n_nom_modem_samples = f->fsk->N;
f->n_max_modem_samples = f->fsk->N + (f->fsk->Ts);
f->n_nat_modem_samples = f->fsk->N;
f->nin = fsk_nin(f->fsk);
f->modem_sample_rate = 8000;
/* Malloc something to appease freedv_init and freedv_destroy */
f->codec_bits = malloc(1);
f->n_protocol_bits = 0;
codec2_mode = CODEC2_MODE_700B;
/* Set up the stats */
fsk_setup_modem_stats(f->fsk,&(f->stats));
}
#endif
f->test_frame_sync_state = 0;
f->total_bits = 0;
f->total_bit_errors = 0;
f->codec2 = codec2_create(codec2_mode);
if (f->codec2 == NULL)
return NULL;
if ((mode == FREEDV_MODE_1600) || (mode == FREEDV_MODE_2400A) || (mode == FREEDV_MODE_2400B)) {
f->n_speech_samples = codec2_samples_per_frame(f->codec2);
f->n_codec_bits = codec2_bits_per_frame(f->codec2);
nbit = f->n_codec_bits;
nbyte = (nbit + 7) / 8;
} else if ((mode == FREEDV_MODE_800XA)) {
f->n_speech_samples = 2*codec2_samples_per_frame(f->codec2);
f->n_codec_bits = codec2_bits_per_frame(f->codec2);
nbit = f->n_codec_bits;
nbyte = (nbit + 7) / 8;
nbyte = nbyte*2;
nbit = 8*nbyte;
f->n_codec_bits = nbit;
} else { /* ((mode == FREEDV_MODE_700) || (mode == FREEDV_MODE_700B)) */
f->n_speech_samples = 2*codec2_samples_per_frame(f->codec2);
f->n_codec_bits = 2*codec2_bits_per_frame(f->codec2);
nbit = f->n_codec_bits;
nbyte = 2*((codec2_bits_per_frame(f->codec2) + 7) / 8);
}
f->prev_rx_bits = (float*)malloc(sizeof(float)*2*codec2_bits_per_frame(f->codec2));
if (f->prev_rx_bits == NULL)
return NULL;
f->packed_codec_bits = (unsigned char*)malloc(nbyte*sizeof(char));
if (mode == FREEDV_MODE_1600)
f->codec_bits = (int*)malloc(nbit*sizeof(int));
if ((mode == FREEDV_MODE_700) || (mode == FREEDV_MODE_700B))
f->codec_bits = (int*)malloc(COHPSK_BITS_PER_FRAME*sizeof(int));
/* Note: VHF Framer/deframer goes directly from packed codec/vc/proto bits to filled frame */
if ((f->packed_codec_bits == NULL) || (f->codec_bits == NULL))
return NULL;
if ((mode == FREEDV_MODE_700) || (mode == FREEDV_MODE_700B)) { // change modem rates to 8000 sps
f->ptFilter7500to8000 = (struct quisk_cfFilter *)malloc(sizeof(struct quisk_cfFilter));
f->ptFilter8000to7500 = (struct quisk_cfFilter *)malloc(sizeof(struct quisk_cfFilter));
quisk_filt_cfInit(f->ptFilter8000to7500, quiskFilt120t480, sizeof(quiskFilt120t480)/sizeof(float));
quisk_filt_cfInit(f->ptFilter7500to8000, quiskFilt120t480, sizeof(quiskFilt120t480)/sizeof(float));
}
else {
f->ptFilter7500to8000 = NULL;
f->ptFilter8000to7500 = NULL;
}
varicode_decode_init(&f->varicode_dec_states, 1);
f->nvaricode_bits = 0;
f->varicode_bit_index = 0;
f->freedv_get_next_tx_char = NULL;
f->freedv_put_next_rx_char = NULL;
f->total_bit_errors = 0;
return f;
}
/*---------------------------------------------------------------------------*\
FUNCTION....: freedv_close
AUTHOR......: David Rowe
DATE CREATED: 3 August 2014
Frees up memory.
\*---------------------------------------------------------------------------*/
void freedv_close(struct freedv *freedv) {
assert(freedv != NULL);
free(freedv->prev_rx_bits);
free(freedv->packed_codec_bits);
free(freedv->codec_bits);
free(freedv->tx_bits);
if (freedv->mode == FREEDV_MODE_1600)
fdmdv_destroy(freedv->fdmdv);
#ifndef CORTEX_M4
if (freedv->mode == FREEDV_MODE_700)
cohpsk_destroy(freedv->cohpsk);
if (freedv->mode == FREEDV_MODE_2400A)
fsk_destroy(freedv->fsk);
if (freedv->mode == FREEDV_MODE_2400B)
fmfsk_destroy(freedv->fmfsk);
#endif
codec2_destroy(freedv->codec2);
if (freedv->ptFilter8000to7500) {
quisk_filt_destroy(freedv->ptFilter8000to7500);
free(freedv->ptFilter8000to7500);
freedv->ptFilter8000to7500 = NULL;
}
if (freedv->ptFilter7500to8000) {
quisk_filt_destroy(freedv->ptFilter7500to8000);
free(freedv->ptFilter7500to8000);
freedv->ptFilter7500to8000 = NULL;
}
free(freedv);
}
/*---------------------------------------------------------------------------*\
FUNCTION....: freedv_tx
AUTHOR......: David Rowe
DATE CREATED: 3 August 2014
Takes a frame of input speech samples, encodes and modulates them to
produce a frame of modem samples that can be sent to the
transmitter. See freedv_tx.c for an example.
speech_in[] is sampled at 8000 Hz, and the user must supply a block
of exactly freedv_get_n_speech_samples(). The speech_in[] level
should be such that the peak speech level is between +/- 16384 and
+/- 32767.
The FDM modem signal mod_out[] is sampled at 8000 Hz and is
freedv_get_n_nom_modem_samples() long. mod_out[] will be scaled
such that the peak level is just less than +/-32767.
The complex-valued output can directly drive an I/Q modulator to
produce a single sideband signal. To generate the other sideband,
take the complex conjugate of mod_out[].
The FreeDV 1600 modem has a high crest factor (around 12dB), however
the energy and duration of the peaks is small. FreeDV 1600 is
usually operated at a "backoff" of 8dB. Adjust the power amplifier
drive so that the average power is 8dB less than the peak power of
the PA. For example, on a radio rated at 100W PEP for SSB, the
average FreeDV power is typically 20W.
The FreeDV 700 modem has a crest factor of about 8dB (with
f->clip=1, the default), so if your PA can handle it, it can be
driven harder than FreeDV 1600. Caution - some PAs cannot handle a
high continuous power. A conservative level is 20W average for a
100W PEP rated PA.
\*---------------------------------------------------------------------------*/
/* real-valued short sample output, useful for going straight to DAC */
/* TX routines for 2400 FSK modes, after codec2 encoding */
#ifndef CORTEX_M4
static void freedv_tx_fsk_voice(struct freedv *f, short mod_out[]) {
int i;
float *tx_float; /* To hold on to modulated samps from fsk/fmfsk */
uint8_t vc_bits[2]; /* Varicode bits for 2400 framing */
uint8_t proto_bits[3]; /* Prococol bits for 2400 framing */
/* Frame for 2400A/B */
if(f->mode == FREEDV_MODE_2400A || f->mode == FREEDV_MODE_2400B){
/* Get varicode bits for TX and possibly ask for a new char */
/* 2 bits per 2400A/B frame, so this has to be done twice */
for(i=0;i<2;i++){
if (f->nvaricode_bits) {
vc_bits[i] = f->tx_varicode_bits[f->varicode_bit_index++];
f->nvaricode_bits--;
}
if (f->nvaricode_bits == 0) {
/* get new char and encode */
char s[2];
if (f->freedv_get_next_tx_char != NULL) {
s[0] = (*f->freedv_get_next_tx_char)(f->callback_state);
f->nvaricode_bits = varicode_encode(f->tx_varicode_bits, s, VARICODE_MAX_BITS, 1, 1);
f->varicode_bit_index = 0;
}
}
}
/* If the API user hasn't set up message callbacks, don't bother with varicode bits */
if(f->freedv_get_next_proto != NULL){
(*f->freedv_get_next_proto)(f->proto_callback_state,(char*)proto_bits);
fvhff_frame_bits(FREEDV_VHF_FRAME_A,(uint8_t*)(f->tx_bits),(uint8_t*)(f->packed_codec_bits),proto_bits,vc_bits);
}else if(f->freedv_get_next_tx_char != NULL){
fvhff_frame_bits(FREEDV_VHF_FRAME_A,(uint8_t*)(f->tx_bits),(uint8_t*)(f->packed_codec_bits),NULL,vc_bits);
}else {
fvhff_frame_bits(FREEDV_VHF_FRAME_A,(uint8_t*)(f->tx_bits),(uint8_t*)(f->packed_codec_bits),NULL,NULL);
}
/* Frame for 800XA */
}else if(f->mode == FREEDV_MODE_800XA){
fvhff_frame_bits(FREEDV_HF_FRAME_B,(uint8_t*)(f->tx_bits),(uint8_t*)(f->packed_codec_bits),NULL,NULL);
}
/* Allocate floating point buffer for FSK mod */
tx_float = alloca(sizeof(float)*f->n_nom_modem_samples);
/* do 4fsk mod */
if(f->mode == FREEDV_MODE_2400A || f->mode == FREEDV_MODE_800XA){
fsk_mod(f->fsk,tx_float,(uint8_t*)(f->tx_bits));
/* Convert float samps to short */
for(i=0; i<f->n_nom_modem_samples; i++){
mod_out[i] = (short)(tx_float[i]*FSK_SCALE);
}
/* do me-fsk mod */
}else if(f->mode == FREEDV_MODE_2400B){
fmfsk_mod(f->fmfsk,tx_float,(uint8_t*)(f->tx_bits));
/* Convert float samps to short */
for(i=0; i<f->n_nom_modem_samples; i++){
mod_out[i] = (short)(tx_float[i]*FMFSK_SCALE);
}
}
}
#endif
/* TX routines for 2400 FSK modes, data channel */
#ifndef CORTEX_M4
static void freedv_tx_fsk_data(struct freedv *f, short mod_out[]) {
int i;
float *tx_float; /* To hold on to modulated samps from fsk/fmfsk */
fvhff_frame_data_bits(f->deframer, FREEDV_VHF_FRAME_A,(uint8_t*)(f->tx_bits));
/* Allocate floating point buffer for FSK mod */
tx_float = alloca(sizeof(float)*f->n_nom_modem_samples);
/* do 4fsk mod */
if(f->mode == FREEDV_MODE_2400A){
fsk_mod(f->fsk,tx_float,(uint8_t*)(f->tx_bits));
/* Convert float samps to short */
for(i=0; i<f->n_nom_modem_samples; i++){
mod_out[i] = (short)(tx_float[i]*FSK_SCALE);
}
/* do me-fsk mod */
}else if(f->mode == FREEDV_MODE_2400B){
fmfsk_mod(f->fmfsk,tx_float,(uint8_t*)(f->tx_bits));
/* Convert float samps to short */
for(i=0; i<f->n_nom_modem_samples; i++){
mod_out[i] = (short)(tx_float[i]*FMFSK_SCALE);
}
}
}
#endif
void freedv_tx(struct freedv *f, short mod_out[], short speech_in[]) {
assert(f != NULL);
COMP tx_fdm[f->n_nom_modem_samples];
int i;
assert((f->mode == FREEDV_MODE_1600) || (f->mode == FREEDV_MODE_700) ||
(f->mode == FREEDV_MODE_700B) || (f->mode == FREEDV_MODE_2400A) ||
(f->mode == FREEDV_MODE_2400B) || (f->mode == FREEDV_MODE_800XA));
/* FSK and MEFSK/FMFSK modems work only on real samples. It's simpler to just
* stick them in the real sample tx/rx functions than to add a comp->real converter
* to comptx */
if((f->mode == FREEDV_MODE_2400A) || (f->mode == FREEDV_MODE_2400B) || (f->mode == FREEDV_MODE_800XA)){
#ifndef CORTEX_M4
/* 800XA has two codec frames per modem frame */
if((f->mode == FREEDV_MODE_800XA)){
codec2_encode(f->codec2, &f->packed_codec_bits[0], &speech_in[ 0]);
codec2_encode(f->codec2, &f->packed_codec_bits[4], &speech_in[320]);
}else{
codec2_encode(f->codec2, f->packed_codec_bits, speech_in);
}
freedv_tx_fsk_voice(f, mod_out);
#endif
}else{
freedv_comptx(f, tx_fdm, speech_in);
for(i=0; i<f->n_nom_modem_samples; i++)
mod_out[i] = tx_fdm[i].real;
}
}
/* complex valued output, useful for suitable for single sided freq shifting */
static void freedv_comptx_fdmdv_1600(struct freedv *f, COMP mod_out[]) {
int bit, byte, i, j;
int bits_per_codec_frame, bits_per_modem_frame;
int data, codeword1, data_flag_index;
COMP tx_fdm[f->n_nat_modem_samples];
bits_per_codec_frame = codec2_bits_per_frame(f->codec2);
bits_per_modem_frame = fdmdv_bits_per_frame(f->fdmdv);
/* unpack bits, MSB first */
bit = 7; byte = 0;
for(i=0; i<bits_per_codec_frame; i++) {
f->codec_bits[i] = (f->packed_codec_bits[byte] >> bit) & 0x1;
bit--;
if (bit < 0) {
bit = 7;
byte++;
}
}
// spare bit in frame that codec defines. Use this 1
// bit/frame to send txt messages
data_flag_index = codec2_get_spare_bit_index(f->codec2);
if (f->nvaricode_bits) {
f->codec_bits[data_flag_index] = f->tx_varicode_bits[f->varicode_bit_index++];
f->nvaricode_bits--;
}
if (f->nvaricode_bits == 0) {
/* get new char and encode */
char s[2];
if (f->freedv_get_next_tx_char != NULL) {
s[0] = (*f->freedv_get_next_tx_char)(f->callback_state);
f->nvaricode_bits = varicode_encode(f->tx_varicode_bits, s, VARICODE_MAX_BITS, 1, 1);
f->varicode_bit_index = 0;
}
}
/* Protect first 12 out of first 16 excitation bits with (23,12) Golay Code:
0,1,2,3: v[0]..v[1]
4,5,6,7: MSB of pitch
11,12,13,14: MSB of energy
*/
data = 0;
for(i=0; i<8; i++) {
data <<= 1;
data |= f->codec_bits[i];
}
for(i=11; i<15; i++) {
data <<= 1;
data |= f->codec_bits[i];
}
codeword1 = golay23_encode(data);
/* now pack output frame with parity bits at end to make them
as far apart as possible from the data they protect. Parity
bits are LSB of the Golay codeword */
for(i=0; i<bits_per_codec_frame; i++)
f->tx_bits[i] = f->codec_bits[i];
for(j=0; i<bits_per_codec_frame+11; i++,j++) {
f->tx_bits[i] = (codeword1 >> (10-j)) & 0x1;
}
f->tx_bits[i] = 0; /* spare bit */
/* optionally overwrite with test frames */
if (f->test_frames) {
fdmdv_get_test_bits(f->fdmdv, f->tx_bits);
fdmdv_get_test_bits(f->fdmdv, &f->tx_bits[bits_per_modem_frame]);
//fprintf(stderr, "test frames on tx\n");
}
/* modulate even and odd frames */
fdmdv_mod(f->fdmdv, tx_fdm, f->tx_bits, &f->tx_sync_bit);
assert(f->tx_sync_bit == 1);
fdmdv_mod(f->fdmdv, &tx_fdm[FDMDV_NOM_SAMPLES_PER_FRAME], &f->tx_bits[bits_per_modem_frame], &f->tx_sync_bit);
assert(f->tx_sync_bit == 0);
assert(2*FDMDV_NOM_SAMPLES_PER_FRAME == f->n_nom_modem_samples);
for(i=0; i<f->n_nom_modem_samples; i++)
mod_out[i] = fcmult(FDMDV_SCALE, tx_fdm[i]);
}
#ifndef CORTEX_M4
static void freedv_comptx_fdmdv_700(struct freedv *f, COMP mod_out[]) {
int bit, byte, i, j, k;
int bits_per_codec_frame, bits_per_modem_frame;
int data_flag_index, nspare;
COMP tx_fdm[f->n_nat_modem_samples];
bits_per_codec_frame = codec2_bits_per_frame(f->codec2);
bits_per_modem_frame = COHPSK_BITS_PER_FRAME;
byte = 0;
for (j=0; j<bits_per_modem_frame; j+=bits_per_codec_frame) {
/* unpack bits, MSB first */
bit = 7;
for(i=0; i<bits_per_codec_frame; i++) {
f->codec_bits[j+i] = (f->packed_codec_bits[byte] >> bit) & 0x1;
bit--;
if (bit < 0) {
bit = 7;
byte++;
}
}
if (bit != 7)
byte++;
// spare bits in frame that codec defines. Use these spare
// bits/frame to send txt messages
if (f->mode == FREEDV_MODE_700)
nspare = 2;
else
nspare = 1; // Just one spare bit for FREEDV_MODE_700B
data_flag_index = codec2_get_spare_bit_index(f->codec2);
for(k=0; k<nspare; k++) {
if (f->nvaricode_bits) {
f->codec_bits[j+data_flag_index+k] = f->tx_varicode_bits[f->varicode_bit_index++];
//fprintf(stderr, "%d %d\n", j+data_flag_index+k, f->codec_bits[j+data_flag_index+k]);
f->nvaricode_bits--;
}
if (f->nvaricode_bits == 0) {
/* get new char and encode */
char s[2];
if (f->freedv_get_next_tx_char != NULL) {
s[0] = (*f->freedv_get_next_tx_char)(f->callback_state);
f->nvaricode_bits = varicode_encode(f->tx_varicode_bits, s, VARICODE_MAX_BITS, 1, 1);
f->varicode_bit_index = 0;
}
}
}
}
/* optionally ovwerwrite the codec bits with test frames */
if (f->test_frames) {
cohpsk_get_test_bits(f->cohpsk, f->codec_bits);
}
/* cohpsk modulator */
cohpsk_mod(f->cohpsk, tx_fdm, f->codec_bits);
if (f->clip)
cohpsk_clip(tx_fdm);
for(i=0; i<f->n_nat_modem_samples; i++)
mod_out[i] = fcmult(FDMDV_SCALE*NORM_PWR, tx_fdm[i]);
i = quisk_cfInterpDecim(mod_out, f->n_nat_modem_samples, f->ptFilter7500to8000, 16, 15);
//assert(i == f->n_nom_modem_samples);
// Caution: assert fails if f->n_nat_modem_samples * 16.0 / 15.0 is not an integer
}
#endif
void freedv_comptx(struct freedv *f, COMP mod_out[], short speech_in[]) {
assert(f != NULL);
int i, j;
int bits_per_codec_frame;
short tx_real[f->n_nom_modem_samples];
assert((f->mode == FREEDV_MODE_1600) || (f->mode == FREEDV_MODE_700) ||
(f->mode == FREEDV_MODE_700B) || (f->mode == FREEDV_MODE_2400A) ||
(f->mode == FREEDV_MODE_2400B));
if (f->mode == FREEDV_MODE_1600) {
codec2_encode(f->codec2, f->packed_codec_bits, speech_in);
freedv_comptx_fdmdv_1600(f, mod_out);
}
#ifndef CORTEX_M4
if ((f->mode == FREEDV_MODE_700) || (f->mode == FREEDV_MODE_700B)) {
bits_per_codec_frame = codec2_bits_per_frame(f->codec2);
int bytes_per_codec_frame = (bits_per_codec_frame + 7) / 8;
int codec_frames = f->n_codec_bits / bits_per_codec_frame;
for (j=0; j < codec_frames; j++) {
codec2_encode(f->codec2, f->packed_codec_bits + j * bytes_per_codec_frame, speech_in);
speech_in += codec2_samples_per_frame(f->codec2);
}
freedv_comptx_fdmdv_700(f, mod_out);
}
/* 2400 A and B are handled by the real-mode TX */
if((f->mode == FREEDV_MODE_2400A) || (f->mode == FREEDV_MODE_2400B)){
freedv_tx(f,tx_real,speech_in);
/* Convert to complex-mode */
for(i=0; i<f->n_nom_modem_samples; i++){
mod_out[i].real = (float) tx_real[i];
mod_out[i].imag = 0;
}
}
#endif
}
void freedv_codectx(struct freedv *f, short mod_out[], unsigned char *packed_codec_bits) {
assert(f != NULL);
COMP tx_fdm[f->n_nom_modem_samples];
int bits_per_codec_frame;
int bytes_per_codec_frame;
int codec_frames;
int i;
bits_per_codec_frame = codec2_bits_per_frame(f->codec2);
bytes_per_codec_frame = (bits_per_codec_frame + 7) / 8;
codec_frames = f->n_codec_bits / bits_per_codec_frame;
memcpy(f->packed_codec_bits, packed_codec_bits, bytes_per_codec_frame * codec_frames);
switch(f->mode) {
case FREEDV_MODE_1600:
freedv_comptx_fdmdv_1600(f, tx_fdm);
break;
#ifndef CORTEX_M4
case FREEDV_MODE_700:
case FREEDV_MODE_700B:
freedv_comptx_fdmdv_700(f, tx_fdm);
break;
case FREEDV_MODE_2400A:
case FREEDV_MODE_2400B:
freedv_tx_fsk_voice(f, mod_out);
return; /* output is already real */
#endif
}
/* convert complex to real */
for(i=0; i<f->n_nom_modem_samples; i++)
mod_out[i] = tx_fdm[i].real;
}
void freedv_datatx (struct freedv *f, short mod_out[]){
assert(f != NULL);
#ifndef CORTEX_M4
if (f->mode == FREEDV_MODE_2400A || f->mode == FREEDV_MODE_2400B) {
freedv_tx_fsk_data(f, mod_out);
}
#endif
}
int freedv_data_ntxframes (struct freedv *f){
assert(f != NULL);
#ifndef CORTEX_M4
if (f->mode == FREEDV_MODE_2400A || f->mode == FREEDV_MODE_2400B) {
if (f->deframer->fdc)
return freedv_data_get_n_tx_frames(f->deframer->fdc);
}
#endif
return 0;
}
int freedv_nin(struct freedv *f) {
if ((f->mode == FREEDV_MODE_700) || (f->mode == FREEDV_MODE_700B))
// For mode 700, the input rate is 8000 sps, but the modem rate is 7500 sps
// For mode 700, we request a larger number of Rx samples that will be decimated to f->nin samples
return (16 * f->nin + f->ptFilter8000to7500->decim_index) / 15;
else
return f->nin;
}
/*---------------------------------------------------------------------------*\
FUNCTION....: freedv_rx
AUTHOR......: David Rowe
DATE CREATED: 3 August 2014
Takes a frame of samples from the radio receiver, demodulates and
decodes them, producing a frame of decoded speech samples. See
freedv_rx.c for an example.
demod_in[] is a block of received samples sampled at 8000 Hz.
To account for difference in the transmit and receive sample clock
frequencies, the number of demod_in[] samples is time varying. You
MUST call freedv_nin() BEFORE each call to freedv_rx() and pass
exactly that many samples to this function.
To help set your buffer sizes, The maximum value of freedv_nin() is
freedv_get_n_max_modem_samples().
freedv_rx() returns the number of output speech samples available in
speech_out[], which is sampled at 8000 Hz. You should ALWAYS check
the return value of freedv_rx(), and read EXACTLY that number of
speech samples from speech_out[].
1600 mode: When out of sync, it the number of output speech samples
returned will be freedv_nin(). When in sync to a valid FreeDV 1600
signal, the number of output speech samples will alternate between
freedv_get_n_speech_samples() and 0.
700 and 700B mode: The number of output speech samples returned will
always be freedv_get_n_speech_samples(), regardless of sync.
The peak level of demod_in[] is not critical, as the demod works
well over a wide range of amplitude scaling. However avoid clipping
(overload, or samples pinned to +/- 32767). speech_out[] will peak
at just less than +/-32767.
When out of sync, this function echoes the demod_in[] samples to
speech_out[]. This allows the user to listen to the channel, which
is useful for tuning FreeDV signals or reception of non-FreeDV
signals. Setting the squelch with freedv_set_squelch_en(1) will
return zero-valued samples instead.
\*---------------------------------------------------------------------------*/
// short version
int freedv_rx(struct freedv *f, short speech_out[], short demod_in[]) {
assert(f != NULL);
COMP rx_fdm[f->n_max_modem_samples];
int i;
int nin = freedv_nin(f);
assert(nin <= f->n_max_modem_samples);
#ifndef CORTEX_M4
/* Moved inside of cortex_m4 ifdef to silence unused var warning */
float rx_float[f->n_max_modem_samples];
/* FSK RX happens in real floats, so convert to those and call their demod here */
if( (f->mode == FREEDV_MODE_2400A) || (f->mode == FREEDV_MODE_2400B) || (f->mode == FREEDV_MODE_800XA) ){
for(i=0; i<nin; i++) {
rx_float[i] = ((float)demod_in[i]);
}
return freedv_floatrx(f,speech_out,rx_float);
}
#endif
if( (f->mode == FREEDV_MODE_1600) || (f->mode == FREEDV_MODE_700) || (f->mode == FREEDV_MODE_700B)){
/* FDM RX happens with complex samps, so do that */
for(i=0; i<nin; i++) {
rx_fdm[i].real = (float)demod_in[i];
rx_fdm[i].imag = 0.0;
}
return freedv_comprx(f, speech_out, rx_fdm);
}
return 0; /* should never get here */
}
// float input samples version
#ifndef CORTEX_M4
int freedv_floatrx_fsk(struct freedv *f, float demod_in[], int *valid) {
/* Varicode and protocol bits */
uint8_t vc_bits[2];
uint8_t proto_bits[3];
short vc_bit;
int i;
int n_ascii;
char ascii_out;
if(f->mode == FREEDV_MODE_2400A || f->mode == FREEDV_MODE_800XA){
fsk_demod(f->fsk,(uint8_t*)f->tx_bits,demod_in);
f->nin = fsk_nin(f->fsk);
}else{
fmfsk_demod(f->fmfsk,(uint8_t*)f->tx_bits,demod_in);
f->nin = fmfsk_nin(f->fmfsk);
}
if(fvhff_deframe_bits(f->deframer,f->packed_codec_bits,proto_bits,vc_bits,(uint8_t*)f->tx_bits)){
/* Decode varicode text */
for(i=0; i<2; i++){
/* Note: deframe_bits spits out bits in uint8_ts while varicode_decode expects shorts */
vc_bit = vc_bits[i];
n_ascii = varicode_decode(&f->varicode_dec_states, &ascii_out, &vc_bit, 1, 1);
if (n_ascii && (f->freedv_put_next_rx_char != NULL)) {
(*f->freedv_put_next_rx_char)(f->callback_state, ascii_out);
}
}
/* Pass proto bits on down if callback is present */
if( f->freedv_put_next_proto != NULL){
(*f->freedv_put_next_proto)(f->proto_callback_state,(char*)proto_bits);
}
*valid = 1;
} else {
/* Fill with silence */
*valid = 0;
}
f->sync = f->deframer->state;
f->stats.sync = f->deframer->state;
return f->n_speech_samples;
}
#endif
int freedv_floatrx(struct freedv *f, short speech_out[], float demod_in[]) {
assert(f != NULL);
COMP rx_fdm[f->n_max_modem_samples];
int i;
int nin = freedv_nin(f);
assert(nin <= f->n_max_modem_samples);
/* FSK RX happens in real floats, so demod for those goes here */
#ifndef CORTEX_M4
if( (f->mode == FREEDV_MODE_2400A) || (f->mode == FREEDV_MODE_2400B) || (f->mode == FREEDV_MODE_800XA)){
int valid;
int nout = freedv_floatrx_fsk(f, demod_in, &valid);
if (valid == 0)
for (i = 0; i < nout; i++)
speech_out[i] = 0;
else if (valid < 0)
for (i = 0; i < nout; i++)
speech_out[i] = demod_in[i];
else {
int bits_per_codec_frame = codec2_bits_per_frame(f->codec2);
int bytes_per_codec_frame = (bits_per_codec_frame + 7) / 8;
int frames = f->n_codec_bits / bits_per_codec_frame;
for (i = 0; i < frames; i++) {
codec2_decode(f->codec2, speech_out, f->packed_codec_bits + i * bytes_per_codec_frame);
speech_out += codec2_samples_per_frame(f->codec2);
}
}
return f->n_speech_samples;
}
#endif
if( (f->mode == FREEDV_MODE_1600) || (f->mode == FREEDV_MODE_700) || (f->mode == FREEDV_MODE_700B)){
for(i=0; i<nin; i++) {
rx_fdm[i].real = demod_in[i];
rx_fdm[i].imag = 0;
}
return freedv_comprx(f, speech_out, rx_fdm);
}
return 0; //should never get here
}
// complex input samples version
static int freedv_comprx_fdmdv_1600(struct freedv *f, COMP demod_in[], int *valid) {
int bits_per_codec_frame, bytes_per_codec_frame, bits_per_fdmdv_frame;
int i, j, bit, byte, nin_prev, nout;
int recd_codeword, codeword1, data_flag_index, n_ascii;
short abit[1];
char ascii_out;
int reliable_sync_bit;
bits_per_codec_frame = codec2_bits_per_frame(f->codec2);
bytes_per_codec_frame = (bits_per_codec_frame + 7) / 8;
nout = f->n_speech_samples;
for(i=0; i<f->nin; i++)
demod_in[i] = fcmult(1.0/FDMDV_SCALE, demod_in[i]);
bits_per_fdmdv_frame = fdmdv_bits_per_frame(f->fdmdv);
nin_prev = f->nin;
fdmdv_demod(f->fdmdv, f->fdmdv_bits, &reliable_sync_bit, demod_in, &f->nin);
fdmdv_get_demod_stats(f->fdmdv, &f->stats);
f->sync = f->fdmdv->sync;
f->snr_est = f->stats.snr_est;
if (reliable_sync_bit == 1) {
f->evenframe = 1;
}
if (f->stats.sync) {
if (f->evenframe == 0) {
memcpy(f->rx_bits, f->fdmdv_bits, bits_per_fdmdv_frame*sizeof(int));
nout = 0;
*valid = 0;
}
else {
memcpy(&f->rx_bits[bits_per_fdmdv_frame], f->fdmdv_bits, bits_per_fdmdv_frame*sizeof(int));
if (f->test_frames == 0) {
recd_codeword = 0;
for(i=0; i<8; i++) {
recd_codeword <<= 1;
recd_codeword |= (f->rx_bits[i] & 0x1);
}
for(i=11; i<15; i++) {
recd_codeword <<= 1;
recd_codeword |= (f->rx_bits[i] & 0x1);
}
for(i=bits_per_codec_frame; i<bits_per_codec_frame+11; i++) {
recd_codeword <<= 1;
recd_codeword |= (f->rx_bits[i] & 0x1);
}
codeword1 = golay23_decode(recd_codeword);
f->total_bit_errors += golay23_count_errors(recd_codeword, codeword1);
f->total_bits += 23;
//codeword1 = recd_codeword;
//fprintf(stderr, "received codeword1: 0x%x decoded codeword1: 0x%x\n", recd_codeword, codeword1);
for(i=0; i<bits_per_codec_frame; i++)
f->codec_bits[i] = f->rx_bits[i];
for(i=0; i<8; i++) {
f->codec_bits[i] = (codeword1 >> (22-i)) & 0x1;
}
for(i=8,j=11; i<12; i++,j++) {
f->codec_bits[j] = (codeword1 >> (22-i)) & 0x1;
}
// extract txt msg data bit ------------------------------------------------------------
data_flag_index = codec2_get_spare_bit_index(f->codec2);
abit[0] = f->codec_bits[data_flag_index];
n_ascii = varicode_decode(&f->varicode_dec_states, &ascii_out, abit, 1, 1);
if (n_ascii && (f->freedv_put_next_rx_char != NULL)) {
(*f->freedv_put_next_rx_char)(f->callback_state, ascii_out);
}
// reconstruct missing bit we steal for data bit and decode speech
codec2_rebuild_spare_bit(f->codec2, f->codec_bits);
// pack bits, MSB received first
bit = 7;
byte = 0;
memset(f->packed_codec_bits, 0, bytes_per_codec_frame);
for(i=0; i<bits_per_codec_frame; i++) {
f->packed_codec_bits[byte] |= (f->codec_bits[i] << bit);
bit--;
if(bit < 0) {
bit = 7;
byte++;
}
}
*valid = 1;
}
else {
int test_frame_sync, bit_errors, ntest_bits, k;
short error_pattern[fdmdv_error_pattern_size(f->fdmdv)];
for(k=0; k<2; k++) {
/* test frames, so lets sync up to the test frames and count any errors */
fdmdv_put_test_bits(f->fdmdv, &test_frame_sync, error_pattern, &bit_errors, &ntest_bits, &f->rx_bits[k*bits_per_fdmdv_frame]);
if (test_frame_sync == 1) {
f->test_frame_sync_state = 1;
f->test_frame_count = 0;
}
if (f->test_frame_sync_state) {
if (f->test_frame_count == 0) {
f->total_bit_errors += bit_errors;
f->total_bits += ntest_bits;
if (f->freedv_put_error_pattern != NULL) {
(*f->freedv_put_error_pattern)(f->error_pattern_callback_state, error_pattern, fdmdv_error_pattern_size(f->fdmdv));
}
}
f->test_frame_count++;
if (f->test_frame_count == 4)
f->test_frame_count = 0;
}
//fprintf(stderr, "test_frame_sync: %d test_frame_sync_state: %d bit_errors: %d ntest_bits: %d\n",
// test_frame_sync, f->test_frame_sync_state, bit_errors, ntest_bits);
}
}
/* squelch if beneath SNR threshold or test frames enabled */
if ((f->squelch_en && (f->stats.snr_est < f->snr_squelch_thresh)) || f->test_frames) {
//fprintf(stderr,"squelch %f %f !\n", f->stats.snr_est, f->snr_squelch_thresh);
*valid = 0;
}
nout = f->n_speech_samples;
}
/* note this freewheels if reliable sync dissapears on bad channels */
if (f->evenframe)
f->evenframe = 0;
else
f->evenframe = 1;
//fprintf(stderr,"%d\n", f->evenframe);
} /* if (sync) .... */
else {
/* if not in sync pass through analog samples */
/* this lets us "hear" whats going on, e.g. during tuning */
//fprintf(stderr, "out of sync\n");
if (f->squelch_en == 0) {
*valid = -1;
}
else {
*valid = 0;
}
//fprintf(stderr, "%d %d %d\n", nin_prev, speech_out[0], speech_out[nin_prev-1]);
nout = nin_prev;
}
return nout;
}
#ifndef CORTEX_M4
static int freedv_comprx_fdmdv_700(struct freedv *f, COMP demod_in[], int *valid) {
int bits_per_codec_frame, bytes_per_codec_frame;
int i, j, bit, byte, nout, k;
int data_flag_index, n_ascii, nspare;
short abit[1];
char ascii_out;
float rx_bits[COHPSK_BITS_PER_FRAME];
int sync;
int frames;
bits_per_codec_frame = codec2_bits_per_frame(f->codec2);
bytes_per_codec_frame = (bits_per_codec_frame + 7) / 8;
frames = f->n_codec_bits / bits_per_codec_frame;
nout = f->n_speech_samples;
// echo samples back out as default (say if sync not found)
*valid = -1;
i = quisk_cfInterpDecim(demod_in, freedv_nin(f), f->ptFilter8000to7500, 15, 16);
//if (i != f->nin)
// printf("freedv_comprx decimation: input %d output %d\n", freedv_nin(f), i);
for(i=0; i<f->nin; i++)
demod_in[i] = fcmult(1.0/FDMDV_SCALE, demod_in[i]);
cohpsk_demod(f->cohpsk, rx_bits, &sync, demod_in, &f->nin);
f->sync = sync;
cohpsk_get_demod_stats(f->cohpsk, &f->stats);
f->snr_est = f->stats.snr_est;
memset(f->packed_codec_bits, 0, bytes_per_codec_frame * frames);
if (sync) {
if (f->test_frames == 0) {
data_flag_index = codec2_get_spare_bit_index(f->codec2);
/* optional smoothing of codec symbols */
if (f->smooth_symbols) {
for(i=0; i<bits_per_codec_frame; i++) {
rx_bits[i] += rx_bits[i+bits_per_codec_frame];
rx_bits[i+bits_per_codec_frame] = rx_bits[i];
}
}
byte = 0;
for (j=0; j<COHPSK_BITS_PER_FRAME; j+=bits_per_codec_frame) {
/* extract txt msg data bit(s) */
if (f->mode == FREEDV_MODE_700)
nspare = 2;
else
nspare = 1;
for(k=0; k<nspare; k++) {
abit[0] = rx_bits[data_flag_index+j+k] < 0.0;
n_ascii = varicode_decode(&f->varicode_dec_states, &ascii_out, abit, 1, 1);
if (n_ascii && (f->freedv_put_next_rx_char != NULL)) {
(*f->freedv_put_next_rx_char)(f->callback_state, ascii_out);
}
}
/* pack bits, MSB received first */
bit = 7;
for(i=0; i<bits_per_codec_frame; i++) {
f->packed_codec_bits[byte] |= ((rx_bits[j+i] < 0.0) << bit);
bit--;
if (bit < 0) {
bit = 7;
byte++;
}
}
if (bit != 7)
byte++;
if (f->squelch_en && (f->stats.snr_est < f->snr_squelch_thresh)) {
*valid = 0;
}
*valid = 1;
}
nout = f->n_speech_samples;
}
else {
short error_pattern[COHPSK_BITS_PER_FRAME];
int bit_errors;
/* test data, lets see if we can sync to the test data sequence */
cohpsk_put_test_bits(f->cohpsk, &f->test_frame_sync_state, error_pattern, &bit_errors, rx_bits);
if (f->test_frame_sync_state) {
f->total_bit_errors += bit_errors;
f->total_bits += COHPSK_BITS_PER_FRAME;
if (f->freedv_put_error_pattern != NULL) {
(*f->freedv_put_error_pattern)(f->error_pattern_callback_state, error_pattern, COHPSK_BITS_PER_FRAME);
}
}
*valid = 0;
nout = f->n_speech_samples;
}
}
/* no valid FreeDV signal - squelch output */
if (sync == 0) {
nout = freedv_nin(f);
if (f->squelch_en) {
*valid = 0;
}
}
return nout;
}
#endif
int freedv_comprx(struct freedv *f, short speech_out[], COMP demod_in[]) {
assert(f != NULL);
int bits_per_codec_frame, bytes_per_codec_frame;
int i, nout = 0;
int valid;
assert(f->nin <= f->n_max_modem_samples);
bits_per_codec_frame = codec2_bits_per_frame(f->codec2);
bytes_per_codec_frame = (bits_per_codec_frame + 7) / 8;
if (f->mode == FREEDV_MODE_1600) {
nout = freedv_comprx_fdmdv_1600(f, demod_in, &valid);
}
#ifndef CORTEX_M4
if ((f->mode == FREEDV_MODE_700) || (f->mode == FREEDV_MODE_700B)) {
nout = freedv_comprx_fdmdv_700(f, demod_in, &valid);
}
#endif
if (valid == 0)
for (i = 0; i < nout; i++)
speech_out[i] = 0;
else if (valid < 0)
for (i = 0; i < nout; i++)
speech_out[i] = FDMDV_SCALE*demod_in[i].real;
else {
int frames = f->n_codec_bits / bits_per_codec_frame;
for (i = 0; i < frames; i++) {
codec2_decode(f->codec2, speech_out, f->packed_codec_bits + i * bytes_per_codec_frame);
speech_out += codec2_samples_per_frame(f->codec2);
}
}
//fprintf(stderr,"freedv_nin(f): %d nout: %d\n", freedv_nin(f), nout);
return nout;
}
int freedv_codecrx(struct freedv *f, unsigned char *packed_codec_bits, short demod_in[])
{
assert(f != NULL);
COMP rx_fdm[f->n_max_modem_samples];
int i;
int nin = freedv_nin(f);
int valid;
int ret = 0;
float rx_float[f->n_max_modem_samples];
assert(nin <= f->n_max_modem_samples);
#ifndef CORTEX_M4
/* FSK RX happens in real floats, so convert to those and call their demod here */
if( (f->mode == FREEDV_MODE_2400A) || (f->mode == FREEDV_MODE_2400B) ){
for(i=0; i<nin; i++) {
rx_float[i] = ((float)demod_in[i]);
}
}
#endif
if( (f->mode == FREEDV_MODE_1600) || (f->mode == FREEDV_MODE_700) || (f->mode == FREEDV_MODE_700B)){
for(i=0; i<nin; i++) {
rx_fdm[i].real = (float)demod_in[i];
rx_fdm[i].imag = 0.0;
}
}
if (f->mode == FREEDV_MODE_1600) {
freedv_comprx_fdmdv_1600(f, rx_fdm, &valid);
}
#ifndef CORTEX_M4
if ((f->mode == FREEDV_MODE_700) || (f->mode == FREEDV_MODE_700B)) {
freedv_comprx_fdmdv_700(f, rx_fdm, &valid);
}
if( (f->mode == FREEDV_MODE_2400A) || (f->mode == FREEDV_MODE_2400B) || (f->mode == FREEDV_MODE_800XA)){
freedv_floatrx_fsk(f, rx_float, &valid);
}
#endif
if (valid == 1) {
int bits_per_codec_frame = codec2_bits_per_frame(f->codec2);
int bytes_per_codec_frame = (bits_per_codec_frame + 7) / 8;
int codec_frames = f->n_codec_bits / bits_per_codec_frame;
memcpy(packed_codec_bits, f->packed_codec_bits, bytes_per_codec_frame * codec_frames);
ret = bytes_per_codec_frame * codec_frames;
}
return ret;
}
/*---------------------------------------------------------------------------*\
FUNCTION....: freedv_get_version
AUTHOR......: Jim Ahlstrom
DATE CREATED: 28 July 2015
Return the version of the FreeDV API. This is meant to help API users determine when
incompatible changes have occurred.
\*---------------------------------------------------------------------------*/
int freedv_get_version(void)
{
return VERSION;
}
/*---------------------------------------------------------------------------*\
FUNCTION....: freedv_set_callback_txt
AUTHOR......: Jim Ahlstrom
DATE CREATED: 28 July 2015
Set the callback functions and the callback state pointer that will be used
for the aux txt channel. The freedv_callback_rx is a function pointer that
will be called to return received characters. The freedv_callback_tx is a
function pointer that will be called to send transmitted characters. The callback
state is a user-defined void pointer that will be passed to the callback functions.
Any or all can be NULL, and the default is all NULL.
The function signatures are:
void receive_char(void *callback_state, char c);
char transmit_char(void *callback_state);
\*---------------------------------------------------------------------------*/
void freedv_set_callback_txt(struct freedv *f, freedv_callback_rx rx, freedv_callback_tx tx, void *state)
{
f->freedv_put_next_rx_char = rx;
f->freedv_get_next_tx_char = tx;
f->callback_state = state;
}
/*---------------------------------------------------------------------------*\
FUNCTION....: freedv_set_callback_protocol
AUTHOR......: Brady OBrien
DATE CREATED: 21 February 2016
Set the callback functions and callback pointer that will be used for the
protocol data channel. freedv_callback_protorx will be called when a frame
containing protocol data arrives. freedv_callback_prototx will be called
when a frame containing protocol information is being generated. Protocol
information is intended to be used to develop protocols and fancy features
atop VHF freedv, much like those present in DMR.
Protocol bits are to be passed in an msb-first char array
The number of protocol bits are findable with freedv_get_protocol_bits
\*---------------------------------------------------------------------------*/
void freedv_set_callback_protocol(struct freedv *f, freedv_callback_protorx rx, freedv_callback_prototx tx, void *callback_state){
f->freedv_put_next_proto = rx;
f->freedv_get_next_proto = tx;
f->proto_callback_state = callback_state;
}
/*---------------------------------------------------------------------------*\
FUNCTION....: freedv_set_callback_datarx / freedv_set_callback_datatx
AUTHOR......: Jeroen Vreeken
DATE CREATED: 04 March 2016
Set the callback functions and callback pointer that will be used for the
data channel. freedv_callback_datarx will be called when a packet has been
successfully received. freedv_callback_data_tx will be called when
transmission of a new packet can begin.
If the returned size of the datatx callback is zero the data frame is still
generated, but will contain only a header update.
\*---------------------------------------------------------------------------*/
#ifndef CORTEX_M4
void freedv_set_callback_data(struct freedv *f, freedv_callback_datarx datarx, freedv_callback_datatx datatx, void *callback_state) {
if ((f->mode == FREEDV_MODE_2400A) || (f->mode == FREEDV_MODE_2400B)){
if (!f->deframer->fdc)
f->deframer->fdc = freedv_data_channel_create();
if (!f->deframer->fdc)
return;
freedv_data_set_cb_rx(f->deframer->fdc, datarx, callback_state);
freedv_data_set_cb_tx(f->deframer->fdc, datatx, callback_state);
}
}
#endif
/*---------------------------------------------------------------------------*\
FUNCTION....: freedv_set_data_header
AUTHOR......: Jeroen Vreeken
DATE CREATED: 04 March 2016
Set the data header for the data channel.
Header compression will be used whenever packets from this header are sent.
The header will also be used for fill packets when a data frame is requested
without a packet available.
\*---------------------------------------------------------------------------*/
#ifndef CORTEX_M4
void freedv_set_data_header(struct freedv *f, unsigned char *header)
{
if ((f->mode == FREEDV_MODE_2400A) || (f->mode == FREEDV_MODE_2400B)){
if (!f->deframer->fdc)
f->deframer->fdc = freedv_data_channel_create();
if (!f->deframer->fdc)
return;
freedv_data_set_header(f->deframer->fdc, header);
}
}
#endif
/*---------------------------------------------------------------------------*\
FUNCTION....: freedv_get_modem_stats
AUTHOR......: Jim Ahlstrom
DATE CREATED: 28 July 2015
Return data from the modem. The arguments are pointers to the data items. The
pointers can be NULL if the data item is not wanted.
\*---------------------------------------------------------------------------*/
void freedv_get_modem_stats(struct freedv *f, int *sync, float *snr_est)
{
if (f->mode == FREEDV_MODE_1600)
fdmdv_get_demod_stats(f->fdmdv, &f->stats);
#ifndef CORTEX_M4
if ((f->mode == FREEDV_MODE_700) || (f->mode == FREEDV_MODE_700B))
cohpsk_get_demod_stats(f->cohpsk, &f->stats);
#endif
if (sync) *sync = f->stats.sync;
if (snr_est) *snr_est = f->stats.snr_est;
}
/*---------------------------------------------------------------------------*\
FUNCTIONS...: freedv_set_*
AUTHOR......: Jim Ahlstrom
DATE CREATED: 28 July 2015
Set some parameters used by FreeDV. It is possible to write a macro using ## for
this, but I wasn't sure it would be 100% portable.
\*---------------------------------------------------------------------------*/
// Set integers
void freedv_set_test_frames (struct freedv *f, int val) {f->test_frames = val;}
void freedv_set_squelch_en (struct freedv *f, int val) {f->squelch_en = val;}
void freedv_set_total_bit_errors (struct freedv *f, int val) {f->total_bit_errors = val;}
void freedv_set_total_bits (struct freedv *f, int val) {f->total_bits = val;}
void freedv_set_clip (struct freedv *f, int val) {f->clip = val;}
void freedv_set_varicode_code_num (struct freedv *f, int val) {varicode_set_code_num(&f->varicode_dec_states, val);}
// Set floats
void freedv_set_snr_squelch_thresh (struct freedv *f, float val) {f->snr_squelch_thresh = val;}
void freedv_set_callback_error_pattern (struct freedv *f, freedv_calback_error_pattern cb, void *state)
{
f->freedv_put_error_pattern = cb;
f->error_pattern_callback_state = state;
}
/*---------------------------------------------------------------------------*\
FUNCTIONS...: freedv_get_*
AUTHOR......: Jim Ahlstrom
DATE CREATED: 28 July 2015
Get some parameters from FreeDV. It is possible to write a macro using ## for
this, but I wasn't sure it would be 100% portable.
\*---------------------------------------------------------------------------*/
// Get integers
int freedv_get_protocol_bits (struct freedv *f) {return f->n_protocol_bits;}
int freedv_get_mode (struct freedv *f) {return f->mode;}
int freedv_get_test_frames (struct freedv *f) {return f->test_frames;}
int freedv_get_n_speech_samples (struct freedv *f) {return f->n_speech_samples;}
int freedv_get_modem_sample_rate (struct freedv *f) {return f->modem_sample_rate;}
int freedv_get_n_max_modem_samples (struct freedv *f) {return f->n_max_modem_samples;}
int freedv_get_n_nom_modem_samples (struct freedv *f) {return f->n_nom_modem_samples;}
int freedv_get_total_bits (struct freedv *f) {return f->total_bits;}
int freedv_get_total_bit_errors (struct freedv *f) {return f->total_bit_errors;}
int freedv_get_sync (struct freedv *f) {return f->stats.sync;}
int freedv_get_sz_error_pattern (struct freedv *f) {return f->sz_error_pattern;}
// Get floats
struct CODEC2 *freedv_get_codec2 (struct freedv *f){return f->codec2;}
int freedv_get_n_codec_bits (struct freedv *f){return f->n_codec_bits;}
void freedv_get_modem_extended_stats(struct freedv *f, struct MODEM_STATS *stats)
{
if (f->mode == FREEDV_MODE_1600)
fdmdv_get_demod_stats(f->fdmdv, stats);
#ifndef CORTEX_M4
if ((f->mode == FREEDV_MODE_2400A) || (f->mode == FREEDV_MODE_2400B))
memcpy(stats,&(f->stats),sizeof(struct MODEM_STATS));
if ((f->mode == FREEDV_MODE_700) || (f->mode == FREEDV_MODE_700B))
cohpsk_get_demod_stats(f->cohpsk, stats);
#endif
}
/*-- Functions below this line are private, and not meant for public use --*/
/*---------------------------------------------------------------------------*\
FUNCTIONS...: quisk_filt_cfInit
AUTHOR......: Jim Ahlstrom
DATE CREATED: 27 August 2015
Initialize a FIR filter that will be used to change sample rates. These rate
changing filters were copied from Quisk and modified for float samples.
\*---------------------------------------------------------------------------*/
static void quisk_filt_cfInit(struct quisk_cfFilter * filter, float * coefs, int taps)
{ // Prepare a new filter using coefs and taps. Samples are complex.
filter->dCoefs = coefs;
filter->cSamples = (COMP *)malloc(taps * sizeof(COMP));
memset(filter->cSamples, 0, taps * sizeof(COMP));
filter->ptcSamp = filter->cSamples;
filter->nTaps = taps;
filter->cBuf = NULL;
filter->nBuf = 0;
filter->decim_index = 0;
}
/*---------------------------------------------------------------------------*\
FUNCTIONS...: quisk_filt_destroy
AUTHOR......: Jim Ahlstrom
DATE CREATED: 27 August 2015
Destroy the FIR filter and free all resources.
\*---------------------------------------------------------------------------*/
static void quisk_filt_destroy(struct quisk_cfFilter * filter)
{
if (filter->cSamples) {
free(filter->cSamples);
filter->cSamples = NULL;
}
if (filter->cBuf) {
free(filter->cBuf);
filter->cBuf = NULL;
}
}
/*---------------------------------------------------------------------------*\
FUNCTIONS...: quisk_cfInterpDecim
AUTHOR......: Jim Ahlstrom
DATE CREATED: 27 August 2015
Take an array of samples cSamples of length count, multiply the sample rate
by interp, and then divide the sample rate by decim. Return the new number
of samples. Each specific interp and decim will require its own custom
FIR filter.
\*---------------------------------------------------------------------------*/
static int quisk_cfInterpDecim(COMP * cSamples, int count, struct quisk_cfFilter * filter, int interp, int decim)
{ // Interpolate by interp, and then decimate by decim.
// This uses the float coefficients of filter (not the complex). Samples are complex.
int i, k, nOut;
float * ptCoef;
COMP * ptSample;
COMP csample;
if (count > filter->nBuf) { // increase size of sample buffer
filter->nBuf = count * 2;
if (filter->cBuf)
free(filter->cBuf);
filter->cBuf = (COMP *)malloc(filter->nBuf * sizeof(COMP));
}
memcpy(filter->cBuf, cSamples, count * sizeof(COMP));
nOut = 0;
for (i = 0; i < count; i++) {
// Put samples into buffer left to right. Use samples right to left.
*filter->ptcSamp = filter->cBuf[i];
while (filter->decim_index < interp) {
ptSample = filter->ptcSamp;
ptCoef = filter->dCoefs + filter->decim_index;
csample.real = 0;
csample.imag = 0;
for (k = 0; k < filter->nTaps / interp; k++, ptCoef += interp) {
csample.real += (*ptSample).real * *ptCoef;
csample.imag += (*ptSample).imag * *ptCoef;
if (--ptSample < filter->cSamples)
ptSample = filter->cSamples + filter->nTaps - 1;
}
cSamples[nOut].real = csample.real * interp;
cSamples[nOut].imag = csample.imag * interp;
nOut++;
filter->decim_index += decim;
}
if (++filter->ptcSamp >= filter->cSamples + filter->nTaps)
filter->ptcSamp = filter->cSamples;
filter->decim_index = filter->decim_index - interp;
}
return nOut;
}
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