radio95/fm95
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Code Issues Activity

clean up ssb stuff a little

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This commit is contained in:
KubaPro010
2026-02-15 13:27:53 +01:00
parent 6ff653f5d4
commit 36b861b7e5
6 changed files with 46 additions and 45 deletions
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38
modulation/stereo_encoder.c
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@@ -1,45 +1,23 @@
#include "stereo_encoder.h"
#ifdef STEREO_SSB
static void init_delay_line(struct delay_line_t *delay_line, uint32_t sample_rate) {
delay_line->buffer = malloc(sample_rate * sizeof(float));
memset(delay_line->buffer, 0, sample_rate * sizeof(float));
}
static void set_delay_line(struct delay_line_t *delay_line, uint32_t new_delay) {
delay_line->delay = new_delay;
}
static inline float delay_line(struct delay_line_t *delay_line, float in) {
delay_line->buffer[delay_line->idx++] = in;
if (delay_line->idx >= delay_line->delay) delay_line->idx = 0;
return delay_line->buffer[delay_line->idx];
}
static void exit_delay_line(struct delay_line_t *delay_line) {
free(delay_line->buffer);
}
#endif
// 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) {
st->multiplier = multiplier;
st->osc = osc;
st->pilot_volume = pilot_volume;
st->audio_volume = audio_volume;
#ifdef STEREO_SSB
init_delay_line(&st->delay, STEREO_SSB*2+1);
#endif
#ifdef STEREO_SSB
init_delay_line(&st->delay, osc->sample_rate);
set_delay_line(&st->delay, STEREO_SSB*2+1);
#endif
}
#ifdef STEREO_SSB
float stereo_encode(StereoEncoder* st, uint8_t enabled, float left, float right, firhilbf *hilbert) {
#else
float stereo_encode(StereoEncoder* st, uint8_t enabled, float left, float right) {
#endif
float mid = (left+right) * 0.5f;
if(!enabled) return mid * st->audio_volume;
#ifdef STEREO_SSB
mid = delay_line(&st->delay, mid);
#endif
float half_audio = st->audio_volume * 0.5f;
@@ -60,4 +38,8 @@ float stereo_encode(StereoEncoder* st, uint8_t enabled, float left, float right)
#else
return (mid*half_audio) + (signalx1*st->pilot_volume) + ((side*signalx2) * half_audio);
#endif
}
void exit_stereo_encoder(StereoEncoder* st) {
exit_delay_line(&st->delay);
}