Files
osmocom-analog/src/common/emphasis.h
Andreas Eversberg d2472cfca6 Emphasis: Add filter to prevent emphasis above 4000 Hz
Remove obsolete filter from fsk.c.
2017-09-01 18:42:47 +02:00

23 lines
512 B
C

typedef struct emphasis {
struct {
iir_filter_t lp;
double x_last;
double factor;
double amp;
} p;
struct {
iir_filter_t hp;
double y_last;
double factor;
double amp;
} d;
} emphasis_t;
#define CUT_OFF_EMPHASIS_DEFAULT 300.0
int init_emphasis(emphasis_t *state, int samplerate, double cut_off);
void pre_emphasis(emphasis_t *state, sample_t *samples, int num);
void de_emphasis(emphasis_t *state, sample_t *samples, int num);
void dc_filter(emphasis_t *state, sample_t *samples, int num);