ua1zbe
/
dsd-fme_20_06_2023
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Start on rtlsdr

This commit is contained in:
Jared Szechy 2021-01-16 18:29:20 -05:00
parent 290a2204ba
commit 502607a608
8 changed files with 1075 additions and 13 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
CMakeLists.txt
View File

@ -10,6 +10,7 @@ find_package(LibSndFile REQUIRED)
find_package(MBE REQUIRED)
find_package(ITPP REQUIRED)
find_package(LibPortAudio)
find_package(RTLSDR)
include_directories(SYSTEM ${LIBSNDFILE_INCLUDE_DIR} ${MBE_INCLUDE_DIR} ${ITPP_INCLUDE_DIR})
set(LIBS ${MBE_LIBRARY} ${LIBSNDFILE_LIBRARY} ${ITPP_LIBRARY})
@ -20,6 +21,12 @@ if(PORTAUDIO_FOUND)
add_definitions(-DUSE_PORTAUDIO)
endif(PORTAUDIO_FOUND)
if(RTLSDR_FOUND)
include_directories(SYSTEM ${RTLSDR_INCLUDE_DIRS})
list(APPEND LIBS ${RTLSDR_LIBRARIES})
add_definitions(-DUSE_RTLSDR)
endif(RTLSDR_FOUND)
FILE(GLOB SRCS src/*.c src/*.cpp)
FILE(GLOB HEADERS include/*.h include/*.hpp)

4
cmake/FindLibSndFile.cmake
View File

@ -12,5 +12,5 @@ SET(LIBSNDFILE_NAMES ${LIBSNDFILE_NAMES} sndfile libsndfile)
FIND_LIBRARY(LIBSNDFILE_LIBRARY NAMES ${LIBSNDFILE_NAMES})
include(FindPackageHandleStandardArgs)
find_package_handle_standard_args(LIBSNDFILE DEFAULT_MSG LIBSNDFILE_LIBRARY
LIBSNDFILE_INCLUDE_DIR)
find_package_handle_standard_args(LibSndFile DEFAULT_MSG LIBSNDFILE_LIBRARY
LIBSNDFILE_INCLUDE_DIR)

29
cmake/FindRTLSDR.cmake Normal file
View File

@ -0,0 +1,29 @@
# - Try to find rtlsdr - the hardware driver for the realtek chip in the dvb receivers
# Once done this will define
# RTLSDR_FOUND - System has rtlsdr
# RTLSDR_LIBRARIES - The rtlsdr libraries
# RTLSDR_INCLUDE_DIRS - The rtlsdr include directories
# RTLSDR_LIB_DIRS - The rtlsdr library directories
if (NOT RTLSDR_FOUND)
find_package(PkgConfig)
pkg_check_modules(RTLSDR_PKG librtlsdr)
set(RTLSDR_DEFINITIONS ${PC_RTLSDR_CFLAGS_OTHER})
find_path(RTLSDR_INCLUDE_DIR
NAMES rtl-sdr.h
HINTS ${RTLSDR_PKG_INCLUDE_DIRS})
find_library(RTLSDR_LIBRARY
NAMES rtlsdr
HINTS ${RTLSDR_PKG_LIBRARY_DIRS})
set(RTLSDR_LIBRARIES ${RTLSDR_LIBRARY})
set(RTLSDR_INCLUDE_DIRS ${RTLSDR_INCLUDE_DIR})
include(FindPackageHandleStandardArgs)
find_package_handle_standard_args(RTLSDR DEFAULT_MSG RTLSDR_LIBRARY RTLSDR_INCLUDE_DIR)
mark_as_advanced(RTLSDR_INCLUDE_DIR RTLSDR_LIBRARY)
endif (NOT RTLSDR_FOUND)

13
include/dsd.h
View File

@ -58,6 +58,10 @@
#define PA_LATENCY_OUT 0.100
#endif
#ifdef USE_RTLSDR
#include <rtl-sdr.h>
#endif
/*
* global variables
*/
@ -85,7 +89,10 @@ typedef struct
#ifdef USE_PORTAUDIO
PaStream* audio_in_pa_stream;
#endif
int audio_in_type; // 0 for device, 1 for file, 2 for portaudio
#ifdef USE_RTLSDR
rtlsdr_dev_t *rtlSdrDev;
#endif
int audio_in_type; // 0 for device, 1 for file, 2 for portaudio, 3 for rtlsdr
char audio_out_dev[1024];
int audio_out_fd;
SNDFILE *audio_out_file;
@ -317,4 +324,8 @@ void processDSTAR_HD (dsd_opts * opts, dsd_state * state);
short dmr_filter(short sample);
short nxdn_filter(short sample);
void open_rtlsdr_stream();
void cleanup_rtlsdr_stream();
void get_rtlsdr_sample();
#endif // DSD_H

7
src/dsd_audio.c
View File

@ -500,6 +500,13 @@ openAudioInDevice (dsd_opts * opts)
exit(1);
#endif
}
else if(strncmp(opts->audio_in_dev, "rtl:", 3) == 0)
{
printf("USING RTL SDR\n");
opts->audio_in_type = 3;
// Starting the stream will open the device.
}
else
{
struct stat stat_buf;

14
src/dsd_main.c
View File

@ -327,6 +327,13 @@ liveScanner (dsd_opts * opts, dsd_state * state)
return;
}
}
#endif
#ifdef USE_RTLSDR
if(opts->audio_in_type == 3)
{
printf("starting rtl stream\n");
open_rtlsdr_stream();
}
#endif
while (1)
{
@ -411,6 +418,13 @@ cleanupAndExit (dsd_opts * opts, dsd_state * state)
}
#endif
#ifdef USE_RTLSDR
if(opts->audio_in_type == 3)
{
// TODO: cleanup demod threads
}
#endif
printf("\n");
printf("Total audio errors: %i\n", state->debug_audio_errors);
printf("Total header errors: %i\n", state->debug_header_errors);

28
src/dsd_symbol.c
View File

@ -88,18 +88,26 @@ getSymbol (dsd_opts * opts, dsd_state * state, int have_sync)
cleanupAndExit (opts, state);
}
}
else
{
else if (opts->audio_in_type == 2)
{
#ifdef USE_PORTAUDIO
PaError err = Pa_ReadStream( opts->audio_in_pa_stream, &sample, 1 );
if( err != paNoError )
{
fprintf( stderr, "An error occured while using the portaudio input stream\n" );
fprintf( stderr, "Error number: %d\n", err );
fprintf( stderr, "Error message: %s\n", Pa_GetErrorText( err ) );
}
PaError err = Pa_ReadStream( opts->audio_in_pa_stream, &sample, 1 );
if( err != paNoError )
{
fprintf( stderr, "An error occured while using the portaudio input stream\n" );
fprintf( stderr, "Error number: %d\n", err );
fprintf( stderr, "Error message: %s\n", Pa_GetErrorText( err ) );
}
#endif
}
}
else if (opts->audio_in_type == 3)
{
#ifdef USE_RTLSDR
// TODO: need to read demodulated stream here
get_rtlsdr_sample(&sample);
printf("sample: %d\n", sample);
#endif
}
#ifdef TRACE_DSD
state->debug_sample_index++;

986
src/rtl_sdr_fm.cpp Normal file
View File

@ -0,0 +1,986 @@
/*
* rtl-sdr, turns your Realtek RTL2832 based DVB dongle into a SDR receiver
* Copyright (C) 2012 by Steve Markgraf <steve@steve-m.de>
* Copyright (C) 2012 by Hoernchen <la@tfc-server.de>
* Copyright (C) 2012 by Kyle Keen <keenerd@gmail.com>
* Copyright (C) 2013 by Elias Oenal <EliasOenal@gmail.com>
* Copyright (C) 2014 by Kyle Keen <keenerd@gmail.com>
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 2 of the License, or
* (at your option) any later version.
*
* 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 General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <string.h>
#include <signal.h>
#include <pthread.h>
#include <unistd.h>
#include <queue>
#include <rtl-sdr.h>
#define DEFAULT_SAMPLE_RATE 48000
#define DEFAULT_BUF_LENGTH (1 * 16384)
#define MAXIMUM_OVERSAMPLE 16
#define MAXIMUM_BUF_LENGTH (MAXIMUM_OVERSAMPLE * DEFAULT_BUF_LENGTH)
#define AUTO_GAIN -100
#define BUFFER_DUMP 4096
#define FREQUENCIES_LIMIT 1000
static volatile int do_exit = 0;
static int lcm_post[17] = {1,1,1,3,1,5,3,7,1,9,5,11,3,13,7,15,1};
static int ACTUAL_BUF_LENGTH;
static int *atan_lut = NULL;
static int atan_lut_size = 131072; /* 512 KB */
static int atan_lut_coef = 8;
struct dongle_state
{
int exit_flag;
pthread_t thread;
rtlsdr_dev_t *dev;
int dev_index;
uint32_t freq;
uint32_t rate;
int gain;
uint16_t buf16[MAXIMUM_BUF_LENGTH];
uint32_t buf_len;
int ppm_error;
int offset_tuning;
int direct_sampling;
int mute;
struct demod_state *demod_target;
};
struct demod_state
{
int exit_flag;
pthread_t thread;
int16_t lowpassed[MAXIMUM_BUF_LENGTH];
int lp_len;
int16_t lp_i_hist[10][6];
int16_t lp_q_hist[10][6];
int16_t result[MAXIMUM_BUF_LENGTH];
int16_t droop_i_hist[9];
int16_t droop_q_hist[9];
int result_len;
int rate_in;
int rate_out;
int rate_out2;
int now_r, now_j;
int pre_r, pre_j;
int prev_index;
int downsample; /* min 1, max 256 */
int post_downsample;
int output_scale;
int squelch_level, conseq_squelch, squelch_hits, terminate_on_squelch;
int downsample_passes;
int comp_fir_size;
int custom_atan;
int deemph, deemph_a;
int now_lpr;
int prev_lpr_index;
int dc_block, dc_avg;
void (*mode_demod)(struct demod_state*);
pthread_rwlock_t rw;
pthread_cond_t ready;
pthread_mutex_t ready_m;
struct output_state *output_target;
};
struct output_state
{
int exit_flag;
pthread_t thread;
FILE *file;
char *filename;
int16_t result[MAXIMUM_BUF_LENGTH];
int result_len;
int rate;
std::queue<int16_t> queue;
pthread_rwlock_t rw;
pthread_cond_t ready;
pthread_mutex_t ready_m;
};
struct controller_state
{
int exit_flag;
pthread_t thread;
uint32_t freqs[FREQUENCIES_LIMIT];
int freq_len;
int freq_now;
int edge;
int wb_mode;
pthread_cond_t hop;
pthread_mutex_t hop_m;
};
struct dongle_state dongle;
struct demod_state demod;
struct output_state output;
struct controller_state controller;
static void sighandler(int signum)
{
fprintf(stderr, "Signal caught, exiting!\n");
do_exit = 1;
rtlsdr_cancel_async(dongle.dev);
}
#define safe_cond_signal(n, m) pthread_mutex_lock(m); pthread_cond_signal(n); pthread_mutex_unlock(m)
#define safe_cond_wait(n, m) pthread_mutex_lock(m); pthread_cond_wait(n, m); pthread_mutex_unlock(m)
/* {length, coef, coef, coef} and scaled by 2^15
for now, only length 9, optimal way to get +85% bandwidth */
#define CIC_TABLE_MAX 10
int cic_9_tables[][10] = {
{0,},
{9, -156, -97, 2798, -15489, 61019, -15489, 2798, -97, -156},
{9, -128, -568, 5593, -24125, 74126, -24125, 5593, -568, -128},
{9, -129, -639, 6187, -26281, 77511, -26281, 6187, -639, -129},
{9, -122, -612, 6082, -26353, 77818, -26353, 6082, -612, -122},
{9, -120, -602, 6015, -26269, 77757, -26269, 6015, -602, -120},
{9, -120, -582, 5951, -26128, 77542, -26128, 5951, -582, -120},
{9, -119, -580, 5931, -26094, 77505, -26094, 5931, -580, -119},
{9, -119, -578, 5921, -26077, 77484, -26077, 5921, -578, -119},
{9, -119, -577, 5917, -26067, 77473, -26067, 5917, -577, -119},
{9, -199, -362, 5303, -25505, 77489, -25505, 5303, -362, -199},
};
void rotate_90(unsigned char *buf, uint32_t len)
/* 90 rotation is 1+0j, 0+1j, -1+0j, 0-1j
or [0, 1, -3, 2, -4, -5, 7, -6] */
{
uint32_t i;
unsigned char tmp;
for (i=0; i<len; i+=8) {
/* uint8_t negation = 255 - x */
tmp = 255 - buf[i+3];
buf[i+3] = buf[i+2];
buf[i+2] = tmp;
buf[i+4] = 255 - buf[i+4];
buf[i+5] = 255 - buf[i+5];
tmp = 255 - buf[i+6];
buf[i+6] = buf[i+7];
buf[i+7] = tmp;
}
}
void low_pass(struct demod_state *d)
/* simple square window FIR */
{
int i=0, i2=0;
while (i < d->lp_len) {
d->now_r += d->lowpassed[i];
d->now_j += d->lowpassed[i+1];
i += 2;
d->prev_index++;
if (d->prev_index < d->downsample) {
continue;
}
d->lowpassed[i2] = d->now_r; // * d->output_scale;
d->lowpassed[i2+1] = d->now_j; // * d->output_scale;
d->prev_index = 0;
d->now_r = 0;
d->now_j = 0;
i2 += 2;
}
d->lp_len = i2;
}
int low_pass_simple(int16_t *signal2, int len, int step)
// no wrap around, length must be multiple of step
{
int i, i2, sum;
for(i=0; i < len; i+=step) {
sum = 0;
for(i2=0; i2<step; i2++) {
sum += (int)signal2[i + i2];
}
//signal2[i/step] = (int16_t)(sum / step);
signal2[i/step] = (int16_t)(sum);
}
signal2[i/step + 1] = signal2[i/step];
return len / step;
}
void low_pass_real(struct demod_state *s)
/* simple square window FIR */
// add support for upsampling?
{
int i=0, i2=0;
int fast = (int)s->rate_out;
int slow = s->rate_out2;
while (i < s->result_len) {
s->now_lpr += s->result[i];
i++;
s->prev_lpr_index += slow;
if (s->prev_lpr_index < fast) {
continue;
}
s->result[i2] = (int16_t)(s->now_lpr / (fast/slow));
s->prev_lpr_index -= fast;
s->now_lpr = 0;
i2 += 1;
}
s->result_len = i2;
}
void fifth_order(int16_t *data, int length, int16_t *hist)
/* for half of interleaved data */
{
int i;
int16_t a, b, c, d, e, f;
a = hist[1];
b = hist[2];
c = hist[3];
d = hist[4];
e = hist[5];
f = data[0];
/* a downsample should improve resolution, so don't fully shift */
data[0] = (a + (b+e)*5 + (c+d)*10 + f) >> 4;
for (i=4; i<length; i+=4) {
a = c;
b = d;
c = e;
d = f;
e = data[i-2];
f = data[i];
data[i/2] = (a + (b+e)*5 + (c+d)*10 + f) >> 4;
}
/* archive */
hist[0] = a;
hist[1] = b;
hist[2] = c;
hist[3] = d;
hist[4] = e;
hist[5] = f;
}
void generic_fir(int16_t *data, int length, int *fir, int16_t *hist)
/* Okay, not at all generic. Assumes length 9, fix that eventually. */
{
int d, temp, sum;
for (d=0; d<length; d+=2) {
temp = data[d];
sum = 0;
sum += (hist[0] + hist[8]) * fir[1];
sum += (hist[1] + hist[7]) * fir[2];
sum += (hist[2] + hist[6]) * fir[3];
sum += (hist[3] + hist[5]) * fir[4];
sum += hist[4] * fir[5];
data[d] = sum >> 15 ;
hist[0] = hist[1];
hist[1] = hist[2];
hist[2] = hist[3];
hist[3] = hist[4];
hist[4] = hist[5];
hist[5] = hist[6];
hist[6] = hist[7];
hist[7] = hist[8];
hist[8] = temp;
}
}
// define our own complex math ops because ARMv5 has no hardware float
void multiply(int ar, int aj, int br, int bj, int *cr, int *cj)
{
*cr = ar*br - aj*bj;
*cj = aj*br + ar*bj;
}
int polar_discriminant(int ar, int aj, int br, int bj)
{
int cr, cj;
double angle;
multiply(ar, aj, br, -bj, &cr, &cj);
angle = atan2((double)cj, (double)cr);
return (int)(angle / 3.14159 * (1<<14));
}
int fast_atan2(int y, int x)
/* pre scaled for int16 */
{
int yabs, angle;
int pi4=(1<<12), pi34=3*(1<<12); // note pi = 1<<14
if (x==0 && y==0) {
return 0;
}
yabs = y;
if (yabs < 0) {
yabs = -yabs;
}
if (x >= 0) {
angle = pi4 - pi4 * (x-yabs) / (x+yabs);
} else {
angle = pi34 - pi4 * (x+yabs) / (yabs-x);
}
if (y < 0) {
return -angle;
}
return angle;
}
int polar_disc_fast(int ar, int aj, int br, int bj)
{
int cr, cj;
multiply(ar, aj, br, -bj, &cr, &cj);
return fast_atan2(cj, cr);
}
int atan_lut_init(void)
{
int i = 0;
atan_lut = static_cast<int*>(malloc(atan_lut_size * sizeof(int)));
for (i = 0; i < atan_lut_size; i++) {
atan_lut[i] = (int) (atan((double) i / (1<<atan_lut_coef)) / 3.14159 * (1<<14));
}
return 0;
}
int polar_disc_lut(int ar, int aj, int br, int bj)
{
int cr, cj, x, x_abs;
multiply(ar, aj, br, -bj, &cr, &cj);
/* special cases */
if (cr == 0 || cj == 0) {
if (cr == 0 && cj == 0)
{return 0;}
if (cr == 0 && cj > 0)
{return 1 << 13;}
if (cr == 0 && cj < 0)
{return -(1 << 13);}
if (cj == 0 && cr > 0)
{return 0;}
if (cj == 0 && cr < 0)
{return 1 << 14;}
}
/* real range -32768 - 32768 use 64x range -> absolute maximum: 2097152 */
x = (cj << atan_lut_coef) / cr;
x_abs = abs(x);
if (x_abs >= atan_lut_size) {
/* we can use linear range, but it is not necessary */
return (cj > 0) ? 1<<13 : -(1<<13);
}
if (x > 0) {
return (cj > 0) ? atan_lut[x] : atan_lut[x] - (1<<14);
} else {
return (cj > 0) ? (1<<14) - atan_lut[-x] : -atan_lut[-x];
}
return 0;
}
void fm_demod(struct demod_state *fm)
{
int i, pcm;
int16_t *lp = fm->lowpassed;
pcm = polar_discriminant(lp[0], lp[1],
fm->pre_r, fm->pre_j);
fm->result[0] = (int16_t)pcm;
for (i = 2; i < (fm->lp_len-1); i += 2) {
switch (fm->custom_atan) {
case 0:
pcm = polar_discriminant(lp[i], lp[i+1],
lp[i-2], lp[i-1]);
break;
case 1:
pcm = polar_disc_fast(lp[i], lp[i+1],
lp[i-2], lp[i-1]);
break;
case 2:
pcm = polar_disc_lut(lp[i], lp[i+1],
lp[i-2], lp[i-1]);
break;
}
fm->result[i/2] = (int16_t)pcm;
}
fm->pre_r = lp[fm->lp_len - 2];
fm->pre_j = lp[fm->lp_len - 1];
fm->result_len = fm->lp_len/2;
}
void raw_demod(struct demod_state *fm)
{
int i;
for (i = 0; i < fm->lp_len; i++) {
fm->result[i] = (int16_t)fm->lowpassed[i];
}
fm->result_len = fm->lp_len;
}
void deemph_filter(struct demod_state *fm)
{
static int avg; // cheating...
int i, d;
// de-emph IIR
// avg = avg * (1 - alpha) + sample * alpha;
for (i = 0; i < fm->result_len; i++) {
d = fm->result[i] - avg;
if (d > 0) {
avg += (d + fm->deemph_a/2) / fm->deemph_a;
} else {
avg += (d - fm->deemph_a/2) / fm->deemph_a;
}
fm->result[i] = (int16_t)avg;
}
}
void dc_block_filter(struct demod_state *fm)
{
int i, avg;
int64_t sum = 0;
for (i=0; i < fm->result_len; i++) {
sum += fm->result[i];
}
avg = sum / fm->result_len;
avg = (avg + fm->dc_avg * 9) / 10;
for (i=0; i < fm->result_len; i++) {
fm->result[i] -= avg;
}
fm->dc_avg = avg;
}
int rms(int16_t *samples, int len, int step)
/* largely lifted from rtl_power */
{
int i;
long p, t, s;
double dc, err;
p = t = 0L;
for (i=0; i<len; i+=step) {
s = (long)samples[i];
t += s;
p += s * s;
}
/* correct for dc offset in squares */
dc = (double)(t*step) / (double)len;
err = t * 2 * dc - dc * dc * len;
return (int)sqrt((p-err) / len);
}
void full_demod(struct demod_state *d)
{
int i, ds_p;
int sr = 0;
ds_p = d->downsample_passes;
if (ds_p) {
for (i=0; i < ds_p; i++) {
fifth_order(d->lowpassed, (d->lp_len >> i), d->lp_i_hist[i]);
fifth_order(d->lowpassed+1, (d->lp_len >> i) - 1, d->lp_q_hist[i]);
}
d->lp_len = d->lp_len >> ds_p;
/* droop compensation */
if (d->comp_fir_size == 9 && ds_p <= CIC_TABLE_MAX) {
generic_fir(d->lowpassed, d->lp_len,
cic_9_tables[ds_p], d->droop_i_hist);
generic_fir(d->lowpassed+1, d->lp_len-1,
cic_9_tables[ds_p], d->droop_q_hist);
}
} else {
low_pass(d);
}
/* power squelch */
if (d->squelch_level) {
sr = rms(d->lowpassed, d->lp_len, 1);
if (sr < d->squelch_level) {
d->squelch_hits++;
for (i=0; i<d->lp_len; i++) {
d->lowpassed[i] = 0;
}
} else {
d->squelch_hits = 0;}
}
d->mode_demod(d); /* lowpassed -> result */
if (d->mode_demod == &raw_demod) {
return;
}
/* todo, fm noise squelch */
// use nicer filter here too?
if (d->post_downsample > 1) {
d->result_len = low_pass_simple(d->result, d->result_len, d->post_downsample);}
if (d->deemph) {
deemph_filter(d);}
if (d->dc_block) {
dc_block_filter(d);}
if (d->rate_out2 > 0) {
low_pass_real(d);
//arbitrary_resample(d->result, d->result, d->result_len, d->result_len * d->rate_out2 / d->rate_out);
}
}
static void rtlsdr_callback(unsigned char *buf, uint32_t len, void *ctx)
{
int i;
struct dongle_state *s = static_cast<dongle_state*>(ctx);
struct demod_state *d = s->demod_target;
if (do_exit) {
return;}
if (!ctx) {
return;}
if (s->mute) {
for (i=0; i<s->mute; i++) {
buf[i] = 127;}
s->mute = 0;
}
if (!s->offset_tuning) {
rotate_90(buf, len);}
for (i=0; i<(int)len; i++) {
s->buf16[i] = (int16_t)buf[i] - 127;}
pthread_rwlock_wrlock(&d->rw);
memcpy(d->lowpassed, s->buf16, 2*len);
d->lp_len = len;
pthread_rwlock_unlock(&d->rw);
safe_cond_signal(&d->ready, &d->ready_m);
}
static void *dongle_thread_fn(void *arg)
{
printf("starting dongle thread\n");
struct dongle_state *s = static_cast<dongle_state*>(arg);
rtlsdr_read_async(s->dev, rtlsdr_callback, s, 0, s->buf_len);
return 0;
}
static void *demod_thread_fn(void *arg)
{
printf("starting demod thread\n");
struct demod_state *d = static_cast<demod_state*>(arg);
struct output_state *o = d->output_target;
while (!do_exit) {
safe_cond_wait(&d->ready, &d->ready_m);
pthread_rwlock_wrlock(&d->rw);
full_demod(d);
pthread_rwlock_unlock(&d->rw);
if (d->exit_flag) {
do_exit = 1;
}
if (d->squelch_level && d->squelch_hits > d->conseq_squelch) {
d->squelch_hits = d->conseq_squelch + 1; /* hair trigger */
safe_cond_signal(&controller.hop, &controller.hop_m);
continue;
}
pthread_rwlock_wrlock(&o->rw);
memcpy(o->result, d->result, 2*d->result_len);
o->result_len = d->result_len;
pthread_rwlock_unlock(&o->rw);
safe_cond_signal(&o->ready, &o->ready_m);
}
return 0;
}
static void *output_thread_fn(void *arg)
{
printf("starting output thread\n");
struct output_state *s = static_cast<output_state*>(arg);
while (!do_exit) {
// use timedwait and pad out under runs
safe_cond_wait(&s->ready, &s->ready_m);
pthread_rwlock_rdlock(&s->rw);
printf("result_len: %i\n", s->result_len);
for (int i = 0; i < s->result_len; i++)
{
s->queue.push(reinterpret_cast<int16_t>(s->result[i * 2]));
}
printf("queue size: %lu\n", s->queue.size());
// fwrite(s->result, 2, s->result_len, s->file);
pthread_rwlock_unlock(&s->rw);
}
return 0;
}
int nearest_gain(rtlsdr_dev_t *dev, int target_gain)
{
int i, r, err1, err2, count, nearest;
int* gains;
r = rtlsdr_set_tuner_gain_mode(dev, 1);
if (r < 0) {
fprintf(stderr, "WARNING: Failed to enable manual gain.\n");
return r;
}
count = rtlsdr_get_tuner_gains(dev, NULL);
if (count <= 0) {
return 0;
}
gains = static_cast<int*>(malloc(sizeof(int) * count));
count = rtlsdr_get_tuner_gains(dev, gains);
nearest = gains[0];
for (i=0; i<count; i++) {
err1 = abs(target_gain - nearest);
err2 = abs(target_gain - gains[i]);
if (err2 < err1) {
nearest = gains[i];
}
}
free(gains);
return nearest;
}
int verbose_set_frequency(rtlsdr_dev_t *dev, uint32_t frequency)
{
int r;
r = rtlsdr_set_center_freq(dev, frequency);
if (r < 0) {
fprintf(stderr, "WARNING: Failed to set center freq.\n");
} else {
fprintf(stderr, "Tuned to %u Hz.\n", frequency);
}
return r;
}
int verbose_set_sample_rate(rtlsdr_dev_t *dev, uint32_t samp_rate)
{
int r;
r = rtlsdr_set_sample_rate(dev, samp_rate);
if (r < 0) {
fprintf(stderr, "WARNING: Failed to set sample rate.\n");
} else {
fprintf(stderr, "Sampling at %u S/s.\n", samp_rate);
}
return r;
}
int verbose_direct_sampling(rtlsdr_dev_t *dev, int on)
{
int r;
r = rtlsdr_set_direct_sampling(dev, on);
if (r != 0) {
fprintf(stderr, "WARNING: Failed to set direct sampling mode.\n");
return r;
}
if (on == 0) {
fprintf(stderr, "Direct sampling mode disabled.\n");}
if (on == 1) {
fprintf(stderr, "Enabled direct sampling mode, input 1/I.\n");}
if (on == 2) {
fprintf(stderr, "Enabled direct sampling mode, input 2/Q.\n");}
return r;
}
int verbose_offset_tuning(rtlsdr_dev_t *dev)
{
int r;
r = rtlsdr_set_offset_tuning(dev, 1);
if (r != 0) {
fprintf(stderr, "WARNING: Failed to set offset tuning.\n");
} else {
fprintf(stderr, "Offset tuning mode enabled.\n");
}
return r;
}
int verbose_auto_gain(rtlsdr_dev_t *dev)
{
int r;
r = rtlsdr_set_tuner_gain_mode(dev, 0);
if (r != 0) {
fprintf(stderr, "WARNING: Failed to set tuner gain.\n");
} else {
fprintf(stderr, "Tuner gain set to automatic.\n");
}
return r;
}
int verbose_gain_set(rtlsdr_dev_t *dev, int gain)
{
int r;
r = rtlsdr_set_tuner_gain_mode(dev, 1);
if (r < 0) {
fprintf(stderr, "WARNING: Failed to enable manual gain.\n");
return r;
}
r = rtlsdr_set_tuner_gain(dev, gain);
if (r != 0) {
fprintf(stderr, "WARNING: Failed to set tuner gain.\n");
} else {
fprintf(stderr, "Tuner gain set to %0.2f dB.\n", gain/10.0);
}
return r;
}
int verbose_ppm_set(rtlsdr_dev_t *dev, int ppm_error)
{
int r;
if (ppm_error == 0) {
return 0;}
r = rtlsdr_set_freq_correction(dev, ppm_error);
if (r < 0) {
fprintf(stderr, "WARNING: Failed to set ppm error.\n");
} else {
fprintf(stderr, "Tuner error set to %i ppm.\n", ppm_error);
}
return r;
}
int verbose_reset_buffer(rtlsdr_dev_t *dev)
{
int r;
r = rtlsdr_reset_buffer(dev);
if (r < 0) {
fprintf(stderr, "WARNING: Failed to reset buffers.\n");}
return r;
}
static void optimal_settings(int freq, int rate)
{
// giant ball of hacks
// seems unable to do a single pass, 2:1
int capture_freq, capture_rate;
struct dongle_state *d = &dongle;
struct demod_state *dm = &demod;
struct controller_state *cs = &controller;
dm->downsample = (1000000 / dm->rate_in) + 1;
if (dm->downsample_passes) {
dm->downsample_passes = (int)log2(dm->downsample) + 1;
dm->downsample = 1 << dm->downsample_passes;
}
capture_freq = freq;
capture_rate = dm->downsample * dm->rate_in;
if (!d->offset_tuning) {
capture_freq = freq + capture_rate/4;}
capture_freq += cs->edge * dm->rate_in / 2;
dm->output_scale = (1<<15) / (128 * dm->downsample);
if (dm->output_scale < 1) {
dm->output_scale = 1;}
if (dm->mode_demod == &fm_demod) {
dm->output_scale = 1;}
d->freq = (uint32_t)capture_freq;
d->rate = (uint32_t)capture_rate;
}
static void *controller_thread_fn(void *arg)
{
printf("starting controller thread\n");
// thoughts for multiple dongles
// might be no good using a controller thread if retune/rate blocks
int i;
struct controller_state *s = static_cast<controller_state*>(arg);
if (s->wb_mode) {
for (i=0; i < s->freq_len; i++) {
s->freqs[i] += 16000;}
}
/* set up primary channel */
optimal_settings(s->freqs[0], demod.rate_in);
if (dongle.direct_sampling) {
verbose_direct_sampling(dongle.dev, 1);}
if (dongle.offset_tuning) {
verbose_offset_tuning(dongle.dev);}
/* Set the frequency */
verbose_set_frequency(dongle.dev, dongle.freq);
fprintf(stderr, "Oversampling input by: %ix.\n", demod.downsample);
fprintf(stderr, "Oversampling output by: %ix.\n", demod.post_downsample);
fprintf(stderr, "Buffer size: %0.2fms\n",
1000 * 0.5 * (float)ACTUAL_BUF_LENGTH / (float)dongle.rate);
/* Set the sample rate */
verbose_set_sample_rate(dongle.dev, dongle.rate);
fprintf(stderr, "Output at %u Hz.\n", demod.rate_in/demod.post_downsample);
while (!do_exit) {
safe_cond_wait(&s->hop, &s->hop_m);
if (s->freq_len <= 1) {
continue;}
/* hacky hopping */
s->freq_now = (s->freq_now + 1) % s->freq_len;
optimal_settings(s->freqs[s->freq_now], demod.rate_in);
rtlsdr_set_center_freq(dongle.dev, dongle.freq);
dongle.mute = BUFFER_DUMP;
}
return 0;
}
void dongle_init(struct dongle_state *s)
{
s->rate = DEFAULT_SAMPLE_RATE;
s->gain = AUTO_GAIN; // tenths of a dB
s->mute = 0;
s->direct_sampling = 0;
s->offset_tuning = 0;
s->demod_target = &demod;
}
void demod_init(struct demod_state *s)
{
s->rate_in = DEFAULT_SAMPLE_RATE;
s->rate_out = DEFAULT_SAMPLE_RATE;
s->squelch_level = 0;
s->conseq_squelch = 10;
s->terminate_on_squelch = 0;
s->squelch_hits = 11;
s->downsample_passes = 0;
s->comp_fir_size = 0;
s->prev_index = 0;
s->post_downsample = 1; // once this works, default = 4
s->custom_atan = 0;
s->deemph = 0;
s->rate_out2 = -1; // flag for disabled
s->mode_demod = &fm_demod;
s->pre_j = s->pre_r = s->now_r = s->now_j = 0;
s->prev_lpr_index = 0;
s->deemph_a = 0;
s->now_lpr = 0;
s->dc_block = 0;
s->dc_avg = 0;
pthread_rwlock_init(&s->rw, NULL);
pthread_cond_init(&s->ready, NULL);
pthread_mutex_init(&s->ready_m, NULL);
s->output_target = &output;
}
void demod_cleanup(struct demod_state *s)
{
pthread_rwlock_destroy(&s->rw);
pthread_cond_destroy(&s->ready);
pthread_mutex_destroy(&s->ready_m);
}
void output_init(struct output_state *s)
{
s->rate = DEFAULT_SAMPLE_RATE;
pthread_rwlock_init(&s->rw, NULL);
pthread_cond_init(&s->ready, NULL);
pthread_mutex_init(&s->ready_m, NULL);
}
void output_cleanup(struct output_state *s)
{
pthread_rwlock_destroy(&s->rw);
pthread_cond_destroy(&s->ready);
pthread_mutex_destroy(&s->ready_m);
}
void controller_init(struct controller_state *s)
{
s->freqs[0] = 451800000;
s->freq_len = 0;
s->edge = 0;
s->wb_mode = 0;
pthread_cond_init(&s->hop, NULL);
pthread_mutex_init(&s->hop_m, NULL);
}
void controller_cleanup(struct controller_state *s)
{
pthread_cond_destroy(&s->hop);
pthread_mutex_destroy(&s->hop_m);
}
extern "C" void open_rtlsdr_stream();
void open_rtlsdr_stream()
{
printf("+++++ OPEN STREAM +++++\n");
struct sigaction sigact;
int r;
dongle_init(&dongle);
demod_init(&demod);
output_init(&output);
controller_init(&controller);
/* quadruple sample_rate to limit to Δθ to ±π/2 */
demod.rate_in *= demod.post_downsample;
if (!output.rate) output.rate = demod.rate_out;
// sanity_checks();
ACTUAL_BUF_LENGTH = lcm_post[demod.post_downsample] * DEFAULT_BUF_LENGTH;
r = rtlsdr_open(&dongle.dev, (uint32_t)dongle.dev_index);
if (r < 0)
{
fprintf(stderr, "Failed to open rtlsdr device %d.\n", dongle.dev_index);
exit(1);
}
sigact.sa_handler = sighandler;
sigemptyset(&sigact.sa_mask);
sigact.sa_flags = 0;
sigaction(SIGINT, &sigact, NULL);
sigaction(SIGTERM, &sigact, NULL);
sigaction(SIGQUIT, &sigact, NULL);
sigaction(SIGPIPE, &sigact, NULL);
if (demod.deemph) {
demod.deemph_a = (int)round(1.0/((1.0-exp(-1.0/(demod.rate_out * 75e-6)))));
}
/* Set the tuner gain */
if (dongle.gain == AUTO_GAIN) {
verbose_auto_gain(dongle.dev);
} else {
dongle.gain = nearest_gain(dongle.dev, dongle.gain);
verbose_gain_set(dongle.dev, dongle.gain);
}
verbose_ppm_set(dongle.dev, dongle.ppm_error);
/* Reset endpoint before we start reading from it (mandatory) */
verbose_reset_buffer(dongle.dev);
pthread_create(&controller.thread, NULL, controller_thread_fn, (void*)(&controller));
usleep(100000);
pthread_create(&output.thread, NULL, output_thread_fn, (void*)(&output));
pthread_create(&demod.thread, NULL, demod_thread_fn, (void*)(&demod));
pthread_create(&dongle.thread, NULL, dongle_thread_fn, (void*)(&dongle));
printf("done opening stream\n");
}
void cleanup_rtlsdr_stream()
{
rtlsdr_cancel_async(dongle.dev);
pthread_join(dongle.thread, NULL);
safe_cond_signal(&demod.ready, &demod.ready_m);
pthread_join(demod.thread, NULL);
safe_cond_signal(&output.ready, &output.ready_m);
pthread_join(output.thread, NULL);
safe_cond_signal(&controller.hop, &controller.hop_m);
pthread_join(controller.thread, NULL);
//dongle_cleanup(&dongle);
demod_cleanup(&demod);
output_cleanup(&output);
controller_cleanup(&controller);
rtlsdr_close(dongle.dev);
}
extern "C" void get_rtlsdr_sample(int16_t *sample);
void get_rtlsdr_sample(int16_t *sample)
{
printf("getting sample\n");
safe_cond_wait(&output.ready, &output.ready_m);
*sample = output.queue.front();
output.queue.pop();
}