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Passband and Notch Filter Setup; Debug Output;

This commit is contained in:
lwvmobile 2024-03-20 09:03:02 -04:00
parent 35a1b53867
commit 43f6218129
2 changed files with 31 additions and 17 deletions
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9
include/dsd.h
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@ -663,9 +663,8 @@ typedef struct
//new audio filter structs
LPFilter RCFilter;
HPFilter HRCFilter;
LPFilter RCFilter8;
HPFilter HRCFilter8;
// PBFilter PBF;
PBFilter PBF;
NOTCHFilter NF;
LPFilter RCFilterL;
HPFilter HRCFilterL;
LPFilter RCFilterR;
@ -1331,8 +1330,8 @@ long int raw_rms(short *samples, int len, int step);
void init_audio_filters(dsd_state * state);
void lpf(dsd_state * state, short * input, int len);
void hpf(dsd_state * state, short * input, int len);
void lpf8(dsd_state * state, short * input, int len);
void hpf8(dsd_state * state, short * input, int len);
void pbf(dsd_state * state, short * input, int len);
void nf(dsd_state * state, short * input, int len);
//from: https://github.com/NedSimao/FilteringLibrary
void LPFilter_Init(LPFilter *filter, float cutoffFreqHz, float sampleTimeS);
float LPFilter_Update(LPFilter *filter, float v_in);

39
src/3.c
View File

@ -464,10 +464,6 @@ void init_audio_filters (dsd_state * state)
LPFilter_Init(&state->RCFilter, 960, (float)1/(float)48000);
HPFilter_Init(&state->HRCFilter, 960, (float)1/(float)48000);
//still unsure if 8k sounds good or not (may be the walkie-talkie is too close to SDR, even outside)
LPFilter_Init(&state->RCFilter8, 160, (float)1/(float)8000);
HPFilter_Init(&state->HRCFilter8, 160, (float)1/(float)8000);
//left and right variants for stereo output testing on digital voice samples
LPFilter_Init(&state->RCFilterL, 960, (float)1/(float)48000);
HPFilter_Init(&state->HRCFilterL, 960, (float)1/(float)48000);
@ -477,6 +473,9 @@ void init_audio_filters (dsd_state * state)
//PBFilter_Init(PBFilter *filter, float HPF_cutoffFreqHz, float LPF_cutoffFreqHz, float sampleTimeS);
// void NOTCHFilter_Init(NOTCHFilter *filter, float centerFreqHz, float notchWidthHz, float sampleTimeS);
//unclear what we should set up for these, output is super quiet after using them
PBFilter_Init(&state->PBF, 48000, 12000, (float)1/(float)48000);
NOTCHFilter_Init(&state->NF, 48000, 12000, (float)1/(float)48000);
}
@ -487,7 +486,11 @@ void lpf(dsd_state * state, short * input, int len)
{
int i;
for (i = 0; i < len; i++)
input[i] = LPFilter_Update(&state->RCFilter, input[i]);
{
// fprintf (stderr, "\n in: %05d", input[i]);
input[i] = LPFilter_Update(&state->RCFilter, input[i]);
// fprintf (stderr, "\n out: %05d", input[i]);
}
}
//hpf
@ -495,23 +498,35 @@ void hpf(dsd_state * state, short * input, int len)
{
int i;
for (i = 0; i < len; i++)
input[i] = HPFilter_Update(&state->HRCFilter, input[i]);
{
// fprintf (stderr, "\n in: %05d", input[i]);
input[i] = HPFilter_Update(&state->HRCFilter, input[i]);
// fprintf (stderr, "\n out: %05d", input[i]);
}
}
//lpf
void lpf8(dsd_state * state, short * input, int len)
//nf
void nf(dsd_state * state, short * input, int len)
{
int i;
for (i = 0; i < len; i++)
input[i] = LPFilter_Update(&state->RCFilter8, input[i]);
{
// fprintf (stderr, "\n in: %05d", input[i]);
input[i] = NOTCHFilter_Update(&state->NF, input[i]);
// fprintf (stderr, "\n out: %05d", input[i]);
}
}
//hpf
void hpf8(dsd_state * state, short * input, int len)
//pbf
void pbf(dsd_state * state, short * input, int len)
{
int i;
for (i = 0; i < len; i++)
input[i] = HPFilter_Update(&state->HRCFilter8, input[i]);
{
// fprintf (stderr, "\n in: %05d", input[i]);
input[i] = PBFilter_Update(&state->PBF, input[i]);
// fprintf (stderr, "\n out: %05d", input[i]);
}
}
//Generic RMS function derived from RTL_FM (RTL_SDR) RMS code (doesnt' really work correctly outside of RTL)