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@@ -32,6 +32,7 @@
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#define INPUT_DEVICE "FM_Audio.monitor"
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#define OUTPUT_DEVICE "alsa_output.platform-soc_sound.stereo-fallback"
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#define RDS_DEVICE "RDS.monitor"
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#define RDS2_DEVICE "\0" // Disabled, this is for the additional two RDS channels, 71.25 and 76 khz
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#define MPX_DEVICE "FM_MPX.monitor"
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#define SCA_DEVICE "\0" // Disabled
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#define DARC_DEVICE "\0" // Disabled
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@@ -46,8 +47,10 @@
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#define MONO_VOLUME 0.45f // 45%
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#define PILOT_VOLUME 0.09f // 9%
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#define STEREO_VOLUME 0.3f // 30%
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#define RDS_VOLUME 0.06f // 6%
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#define RDS2_VOLUME 0.045f // 4.5%
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#define RDS_VOLUME 0.0475f // 4.75%
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#define RDS2_VOLUME 0.04f // 4%
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#define RDS3_VOLUME 0.0375f // 3.75%
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#define RDS4_VOLUME 0.035f // 3.5%
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#define SCA_VOLUME 0.1f // 10%, needs to be high because this is analog
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#define MPX_VOLUME 1.0f
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@@ -92,7 +95,7 @@ static void stop(int signum) {
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}
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void show_version() {
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printf("fm95 (an FM Processor by radio95) version 1.6\n");
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printf("fm95 (an FM Processor by radio95) version 1.7\n");
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}
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void show_help(char *name) {
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printf(
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@@ -102,14 +105,15 @@ void show_help(char *name) {
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"\t-o,--output\tOverride output device [default: %s]\n"
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"\t-M,--mpx\tOverride MPX input device [default: %s]\n"
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"\t-r,--rds\tOverride RDS95 input device [default: %s]\n"
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"\t-R,--rds2\tOverride the RDS2 additional stream device [default: %s]\n"
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"\t-S,--sca\tOverride the SCA input device [default: %s]\n"
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"\t-d,--darc\tOverride the DARC input device [default: %s]\n"
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"\t-f,--sca_freq\tOverride the SCA frequency [default: %.1f]\n"
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"\t-F,--sca_dev\tOverride the SCA deviation [default: %.2f]\n"
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"\t-C,--sca_clip\tOverride the SCA clipper threshold [default: %.2f]\n"
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"\t-c,--clipper\tOverride the clipper threshold [default: %.2f]\n"
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"\t-O,--polar\tForce Polar Stereo (does not take effect with -m%s)\n"
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"\t-R,--preemp\tOverride preemphasis [default: %.2f µs]\n"
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"\t-O,--polar\tForce Polar Stereo (does not take effect with -s0%s)\n"
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"\t-e,--preemp\tOverride preemphasis [default: %.2f µs]\n"
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"\t-V,--calibrate\tEnable Calibration mode [default: off, option 2 enables a 60 hz square wave instead of the 400 hz sine wave]\n"
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"\t-p,--power\tSet the MPX power [default: %.1f]\n"
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"\t-P,--mpx_dev\tSet the MPX deviation [default: %.1f]\n"
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@@ -120,26 +124,11 @@ void show_help(char *name) {
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,DEFAULT_STEREO
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,INPUT_DEVICE
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,OUTPUT_DEVICE
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#ifdef MPX_DEVICE
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,MPX_DEVICE
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#else
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,"not set"
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#endif
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#ifdef RDS_DEVICE
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,RDS_DEVICE
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#else
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,"not set"
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#endif
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#ifdef SCA_DEVICE
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,RDS2_DEVICE
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,SCA_DEVICE
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#else
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,"not set"
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#endif
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#ifdef DARC_DEVICE
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,DARC_DEVICE
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#else
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,"not set"
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#endif
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,DEFAULT_SCA_FREQUENCY
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,DEFAULT_SCA_DEVIATION
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,DEFAULT_SCA_CLIPPER_THRESHOLD
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@@ -157,7 +146,7 @@ void show_help(char *name) {
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int main(int argc, char **argv) {
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show_version();
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PulseInputDevice mpx_device, rds_device, sca_device, darc_device;
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PulseInputDevice mpx_device, rds_device, rds2_device, sca_device, darc_device;
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PulseInputDevice input_device;
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PulseOutputDevice output_device;
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@@ -174,6 +163,7 @@ int main(int argc, char **argv) {
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char audio_output_device[64] = OUTPUT_DEVICE;
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char audio_mpx_device[64] = MPX_DEVICE;
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char audio_rds_device[64] = RDS_DEVICE;
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char audio_rds2_device[64] = RDS2_DEVICE;
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char audio_sca_device[64] = SCA_DEVICE;
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char audio_darc_device[64] = DARC_DEVICE;
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float preemphasis_tau = DEFAULT_PREEMPHASIS_TAU;
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@@ -188,7 +178,7 @@ int main(int argc, char **argv) {
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// #region Parse Arguments
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int opt;
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const char *short_opt = "s::i:o:M:r:S:d:f:F:C:c:O::R:V::p:P:A:v:D:h";
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const char *short_opt = "s::i:o:M:r:R:S:d:f:F:C:c:O::e:V::p:P:A:v:D:h";
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struct option long_opt[] =
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{
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{"stereo", optional_argument, NULL, 's'},
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@@ -196,6 +186,7 @@ int main(int argc, char **argv) {
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{"output", required_argument, NULL, 'o'},
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{"mpx", required_argument, NULL, 'M'},
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{"rds", required_argument, NULL, 'r'},
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{"rds2", required_argument, NULL, 'R'},
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{"sca", required_argument, NULL, 'S'},
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{"darc", required_argument, NULL, 'd'},
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{"sca_freq", required_argument, NULL, 'f'},
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@@ -203,7 +194,7 @@ int main(int argc, char **argv) {
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{"sca_clip", required_argument, NULL, 'C'},
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{"clipper", required_argument, NULL, 'c'},
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{"polar", optional_argument, NULL, 'O'},
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{"preemp", required_argument, NULL, 'R'},
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{"preemp", required_argument, NULL, 'e'},
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{"calibrate", optional_argument, NULL, 'V'},
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{"power", required_argument, NULL, 'p'},
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{"mpx_dev", required_argument, NULL, 'P'},
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@@ -233,6 +224,9 @@ int main(int argc, char **argv) {
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case 'r': // RDS in
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memcpy(audio_rds_device, optarg, 63);
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break;
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case 'R': // RDS2 in
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memcpy(audio_rds2_device, optarg, 63);
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break;
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case 'S': //SCA in
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memcpy(audio_sca_device, optarg, 63);
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break;
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@@ -255,7 +249,7 @@ int main(int argc, char **argv) {
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if(optarg) polar_stereo = atoi(optarg);
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else polar_stereo = 1;
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break;
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case 'R': // Preemp
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case 'e': // Preemp
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preemphasis_tau = strtof(optarg, NULL)*1.0e-6f;
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break;
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case 'V': // Calibration
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@@ -286,6 +280,7 @@ int main(int argc, char **argv) {
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int mpx_on = (strlen(audio_mpx_device) != 0);
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int rds_on = (strlen(audio_rds_device) != 0);
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int rds2_on = (strlen(audio_rds2_device) != 0);
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int sca_on = (strlen(audio_sca_device) != 0);
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int darc_on = (strlen(audio_darc_device) != 0);
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@@ -332,6 +327,18 @@ int main(int argc, char **argv) {
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return 1;
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}
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}
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if(rds2_on) {
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printf("Connecting to RDS2 device... (%s)\n", audio_rds2_device);
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opentime_pulse_error = init_PulseInputDevice(&rds2_device, sample_rate, 1, "fm95", "RDS2 Input", audio_rds2_device, &input_buffer_atr);
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if (opentime_pulse_error) {
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fprintf(stderr, "Error: cannot open RDS2 device: %s\n", pa_strerror(opentime_pulse_error));
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free_PulseInputDevice(&input_device);
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if(mpx_on) free_PulseInputDevice(&mpx_device);
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if(rds_on) free_PulseInputDevice(&rds_device);
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return 1;
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}
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}
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if(sca_on) {
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printf("Connecting to SCA device... (%s)\n", audio_sca_device);
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@@ -342,6 +349,7 @@ int main(int argc, char **argv) {
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free_PulseInputDevice(&input_device);
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if(mpx_on) free_PulseInputDevice(&mpx_device);
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if(rds_on) free_PulseInputDevice(&rds_device);
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if(rds2_on) free_PulseInputDevice(&rds2_device);
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return 1;
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}
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}
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@@ -355,6 +363,7 @@ int main(int argc, char **argv) {
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free_PulseInputDevice(&input_device);
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if(mpx_on) free_PulseInputDevice(&mpx_device);
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if(rds_on) free_PulseInputDevice(&rds_device);
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if(rds2_on) free_PulseInputDevice(&rds2_device);
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if(sca_on) free_PulseInputDevice(&sca_device);
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return 1;
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}
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@@ -368,6 +377,7 @@ int main(int argc, char **argv) {
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free_PulseInputDevice(&input_device);
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if(mpx_on) free_PulseInputDevice(&mpx_device);
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if(rds_on) free_PulseInputDevice(&rds_device);
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if(rds2_on) free_PulseInputDevice(&rds2_device);
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if(sca_on) free_PulseInputDevice(&sca_device);
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if(darc_on) free_PulseInputDevice(&darc_device);
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return 1;
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@@ -399,6 +409,7 @@ int main(int argc, char **argv) {
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free_PulseInputDevice(&input_device);
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if(mpx_on) free_PulseInputDevice(&mpx_device);
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if(rds_on) free_PulseInputDevice(&rds_device);
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if(rds2_on) free_PulseInputDevice(&rds2_device);
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if(sca_on) free_PulseInputDevice(&sca_device);
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if(darc_on) free_PulseInputDevice(&darc_device);
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free_PulseOutputDevice(&output_device);
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@@ -415,7 +426,7 @@ int main(int argc, char **argv) {
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lpf_l = iirfilt_rrrf_create_prototype(LIQUID_IIRDES_CHEBY2, LIQUID_IIRDES_LOWPASS, LIQUID_IIRDES_SOS, LPF_ORDER, (15000.0f/sample_rate), 0.0f, 1.0f, 40.0f);
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lpf_r = iirfilt_rrrf_create_prototype(LIQUID_IIRDES_CHEBY2, LIQUID_IIRDES_LOWPASS, LIQUID_IIRDES_SOS, LPF_ORDER, (15000.0f/sample_rate), 0.0f, 1.0f, 40.0f);
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iirfilt_rrrf mpx_lpf = iirfilt_rrrf_create_prototype(LIQUID_IIRDES_BUTTER, LIQUID_IIRDES_LOWPASS, LIQUID_IIRDES_SOS, 2, (polar_stereo ? (46250.0f/sample_rate) : (53000.0f/sample_rate)), 0.0f, 1.0f, 1.0f);
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iirfilt_rrrf mpx_lpf = iirfilt_rrrf_create_prototype(LIQUID_IIRDES_BUTTER, LIQUID_IIRDES_LOWPASS, LIQUID_IIRDES_SOS, 1, (polar_stereo ? (46250.0f/sample_rate) : (53000.0f/sample_rate)), 0.0f, 1.0f, 1.0f);
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ResistorCapacitor preemp_l, preemp_r;
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init_preemphasis(&preemp_l, preemphasis_tau, sample_rate);
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@@ -432,8 +443,8 @@ int main(int argc, char **argv) {
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float bs412_audio_gain = 1.0f;
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AGC agc;
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// fs target min max attack relese
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initAGC(&agc, sample_rate, 0.625f, 0.0f, 1.25f, 0.025f, 0.25f);
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// fs target min max attack release
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initAGC(&agc, sample_rate, 0.7071f, 0.0f, 1.5f, 0.05f, 0.25f);
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signal(SIGINT, stop);
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signal(SIGTERM, stop);
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@@ -446,6 +457,10 @@ int main(int argc, char **argv) {
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float rds1_in[BUFFER_SIZE] = {0};
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float rds2_in[BUFFER_SIZE] = {0};
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float rds3_rds4_in[BUFFER_SIZE*2] = {0};
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float rds3_in[BUFFER_SIZE] = {0};
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float rds4_in[BUFFER_SIZE] = {0};
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float darc_data[BUFFER_SIZE*2] = {0}; // DARC data and clock
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float darc_clock[BUFFER_SIZE] = {0};
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float darc_data_out[BUFFER_SIZE] = {0};
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@@ -480,6 +495,14 @@ int main(int argc, char **argv) {
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}
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uninterleave(rds1_rds2_in, rds1_in, rds2_in, BUFFER_SIZE*2);
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}
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if(rds2_on) {
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if((pulse_error = read_PulseInputDevice(&rds2_device, rds3_rds4_in, sizeof(rds3_rds4_in)))) {
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fprintf(stderr, "Error reading from RDS2 device: %s\n", pa_strerror(pulse_error));
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to_run = 0;
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break;
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}
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uninterleave(rds3_rds4_in, rds3_in, rds4_in, BUFFER_SIZE*2);
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}
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if(sca_on) {
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if((pulse_error = read_PulseInputDevice(&sca_device, sca_in, sizeof(sca_in)))) {
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fprintf(stderr, "Error reading from SCA device: %s\n", pa_strerror(pulse_error));
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@@ -500,20 +523,13 @@ int main(int argc, char **argv) {
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float mpx = 0.0f;
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float audio = 0.0f;
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float l_in = left[i];
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float r_in = right[i];
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float current_mpx_in = mpx_in[i];
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float current_rds_in = rds1_in[i];
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float current_rds2_in = rds2_in[i];
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float current_sca_in = sca_in[i];
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if(darc_clock[i] != last_darc_clock) {
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last_darc_clock = darc_clock[i];
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last_darc_data = darc_data_out[i];
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}
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float ready_l = apply_preemphasis(&preemp_l, l_in);
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float ready_r = apply_preemphasis(&preemp_r, r_in);
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float ready_l = apply_preemphasis(&preemp_l, left[i]);
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float ready_r = apply_preemphasis(&preemp_r, right[i]);
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iirfilt_rrrf_execute(lpf_l, ready_l, &ready_l);
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iirfilt_rrrf_execute(lpf_r, ready_r, &ready_r);
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@@ -522,29 +538,35 @@ int main(int argc, char **argv) {
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ready_l = hard_clip(ready_l*audio_volume, clipper_threshold);
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ready_r = hard_clip(ready_r*audio_volume, clipper_threshold);
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float mono = (ready_l + ready_r) / 2.0f;
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audio = mono*MONO_VOLUME;
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float mid = (ready_l + ready_r) / 2.0f;
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audio = mid*MONO_VOLUME;
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if(stereo) {
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float stereo_signal = (ready_l - ready_r) / 2.0f;
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float side = (ready_l - ready_r) / 2.0f;
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float stereo_carrier = get_oscillator_sin_multiplier_ni(&osc, polar_stereo ? 1 : 8); // 31.25 or 38 KHz
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if(polar_stereo) audio += ((stereo_signal+0.2)*stereo_carrier)*STEREO_VOLUME;
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if(polar_stereo) audio += ((side+0.2)*stereo_carrier)*STEREO_VOLUME; // 0.2 in polar stereo because it also includes a carrier wave, so we add a carrier wave via DC
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else {
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float pilot = get_oscillator_sin_multiplier_ni(&osc, 4); // 19 KHz
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mpx += pilot*PILOT_VOLUME;
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audio += (stereo_signal*stereo_carrier)*STEREO_VOLUME;
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audio += (side*stereo_carrier)*STEREO_VOLUME;
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}
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}
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if(rds_on && polar_stereo == 0) {
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float rds_carrier = get_oscillator_cos_multiplier_ni(&osc, 12); // 57 KHz
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mpx += (current_rds_in*rds_carrier)*RDS_VOLUME;
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mpx += (rds1_in[i]*rds_carrier)*RDS_VOLUME;
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if(!darc_on) { // DARC is hardcoded into 76 khz, according to a screenshot of a fm mpx with darc in it, it takes like 65 to 85 khz
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float rds2_carrier_66 = get_oscillator_cos_multiplier_ni(&osc, 14); // 66.5 KHz
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mpx += (current_rds2_in*rds2_carrier_66)*RDS2_VOLUME;
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mpx += (rds2_in[i]*rds2_carrier_66)*RDS2_VOLUME;
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if(rds2_on) {
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float rds2_carrier_71 = get_oscillator_cos_multiplier_ni(&osc, 15); // 71.25 KHz
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float rds2_carrier_76 = get_oscillator_cos_multiplier_ni(&osc, 16); // 76 KHz
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mpx += (rds3_in[i]*rds2_carrier_71)*RDS3_VOLUME;
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mpx += (rds4_in[i]*rds2_carrier_76)*RDS4_VOLUME;
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}
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}
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}
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if(mpx_on) mpx += hard_clip(current_mpx_in, 1.0f)*MPX_VOLUME;
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if(sca_on) mpx += modulate_fm(&sca_mod, hard_clip(current_sca_in, sca_clipper_threshold))*SCA_VOLUME;
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if(mpx_on) mpx += hard_clip(mpx_in[i], 1.0f)*MPX_VOLUME;
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if(sca_on) mpx += modulate_fm(&sca_mod, hard_clip(sca_in[i], sca_clipper_threshold))*SCA_VOLUME;
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if(darc_on && polar_stereo == 0) mpx += hard_clip(refrenced_modulate_fm(&darc_modulator, last_darc_data, 16.0f)*compute_darc_amplitude(stereo*STEREO_VOLUME), 0.1f); // should never be over 10%, the docs say so
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float mpx_only = measure_mpx(&mpx_only_power, mpx * mpx_deviation);
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@@ -558,11 +580,10 @@ int main(int argc, char **argv) {
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audio *= bs412_audio_gain;
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}
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iirfilt_rrrf_execute(mpx_lpf, audio, &audio); // Should have no effect, as audio should be 0-15, and 23-53, this is a filter for 53, assuming the filter is good, this is precaution and recomendation
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audio = hard_clip(audio, 1.0f-mpx); // Prevent clipping, via clipping the audio signal with relation to the mpx signal
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iirfilt_rrrf_execute(mpx_lpf, audio, &audio);
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output[i] = (audio+mpx)*master_volume;
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output[i] = hard_clip((audio+mpx), 1.0f)*master_volume; // Ensure peak deviation of 75 khz, assuming we're calibrated correctly
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if(rds_on || stereo || darc_on) advance_oscillator(&osc);
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}
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