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configs

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KubaPro010
2026-02-15 15:00:20 +01:00
parent b0bea04e96
commit 1089f8d1ea
3 changed files with 51 additions and 53 deletions
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54
modulation/stereo_encoder.c
View File

@@ -1,49 +1,53 @@
#include "stereo_encoder.h"
// Multiplier is the multiplier to get to 19 khz
void init_stereo_encoder(StereoEncoder* st, uint8_t multiplier, Oscillator* osc, float audio_volume, float pilot_volume) {
void init_stereo_encoder(StereoEncoder* st, uint8_t stereo_ssb, uint8_t multiplier, Oscillator* osc, float audio_volume, float pilot_volume) {
st->multiplier = multiplier;
st->osc = osc;
st->pilot_volume = pilot_volume;
st->audio_volume = audio_volume;
#ifdef STEREO_SSB
init_delay_line(&st->delay_pilot, STEREO_SSB*2+1);
init_delay_line(&st->delay, STEREO_SSB*2+1);
#endif
if(stereo_ssb) {
init_delay_line(&st->delay_pilot, stereo_ssb*2+1);
init_delay_line(&st->delay, stereo_ssb*2+1);
st->stereo_hilbert = firhilbf_create(stereo_ssb, 60);
} else st->stereo_hilbert = NULL;
}
float stereo_encode(StereoEncoder* st, uint8_t enabled, float left, float right, firhilbf *hilbert) {
float stereo_encode(StereoEncoder* st, uint8_t enabled, float left, float right) {
float mid = (left+right) * 0.5f;
if(!enabled) return mid * st->audio_volume;
#ifdef STEREO_SSB
mid = delay_line(&st->delay, mid);
#endif
if(st->stereo_hilbert) mid = delay_line(&st->delay, mid);
float half_audio = st->audio_volume * 0.5f;
float side = (left-right) * 0.5f;
#ifdef STEREO_SSB
float complex stereo_hilbert;
firhilbf_r2c_execute(*hilbert, side, &stereo_hilbert);
float signalx2cos = get_oscillator_cos_multiplier_ni(st->osc, st->multiplier * 2.0f);
#endif
float complex stereo_hilbert = 0+0*I;
if(st->stereo_hilbert) firhilbf_r2c_execute(st->stereo_hilbert, side, &stereo_hilbert);
float signalx1 = get_oscillator_sin_multiplier_ni(st->osc, st->multiplier);
#ifdef STEREO_SSB
signalx1 = delay_line(&st->delay_pilot, signalx1);
#endif
float signalx2cos = 0.0f;
if(st->stereo_hilbert) {
signalx1 = delay_line(&st->delay_pilot, signalx1);
signalx2cos = get_oscillator_cos_multiplier_ni(st->osc, st->multiplier * 2.0f);
}
float signalx2 = get_oscillator_sin_multiplier_ni(st->osc, st->multiplier * 2.0f);
#ifdef STEREO_SSB
float stereo = (crealf(stereo_hilbert) * signalx2cos) + (cimagf(stereo_hilbert) * signalx2);
return (mid*half_audio) + (signalx1*st->pilot_volume) + (stereo * half_audio);
#else
return (mid*half_audio) + (signalx1*st->pilot_volume) + ((side*signalx2) * half_audio);
#endif
if(st->stereo_hilbert) {
float stereo = (crealf(stereo_hilbert) * signalx2cos) + (cimagf(stereo_hilbert) * signalx2);
return (mid*half_audio) + (signalx1*st->pilot_volume) + (stereo * half_audio);
} else {
return (mid*half_audio) + (signalx1*st->pilot_volume) + ((side*signalx2) * half_audio);
}
}
void exit_stereo_encoder(StereoEncoder* st) {
exit_delay_line(&st->delay);
exit_delay_line(&st->delay_pilot);
if(st->stereo_hilbert) {
exit_delay_line(&st->delay);
exit_delay_line(&st->delay_pilot);
firhilbf_destroy(st->stereo_hilbert);
st->stereo_hilbert = NULL;
}
}

7
modulation/stereo_encoder.h
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@@ -1,7 +1,5 @@
#pragma once
#define STEREO_SSB 12
#include <stdint.h>
#include "../dsp/oscillator.h"
#include <liquid/liquid.h>
@@ -16,8 +14,9 @@ typedef struct
float pilot_volume;
delay_line_t delay;
delay_line_t delay_pilot;
firhilbf stereo_hilbert;
} StereoEncoder;
void init_stereo_encoder(StereoEncoder *st, uint8_t multiplier, Oscillator *osc, float audio_volume, float pilot_volume);
float stereo_encode(StereoEncoder* st, uint8_t enabled, float left, float right, firhilbf *hilbert);
void init_stereo_encoder(StereoEncoder *st, uint8_t stereo_ssb, uint8_t multiplier, Oscillator *osc, float audio_volume, float pilot_volume);
float stereo_encode(StereoEncoder* st, uint8_t enabled, float left, float right);
void exit_stereo_encoder(StereoEncoder* st);