freq.h

/* Copyright (c) 2017-2018 Mozilla */
/*
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*/

#ifndef FREQ_H
#define FREQ_H

#include "kiss_fft.h"

#define LPC_ORDER 16

#define PREEMPHASIS (0.85f)

#define FRAME_SIZE_5MS (2)
#define OVERLAP_SIZE_5MS (2)
#define TRAINING_OFFSET_5MS (1)

#define WINDOW_SIZE_5MS (FRAME_SIZE_5MS + OVERLAP_SIZE_5MS)

#define FRAME_SIZE (80*FRAME_SIZE_5MS)
#define OVERLAP_SIZE (80*OVERLAP_SIZE_5MS)
#define TRAINING_OFFSET (80*TRAINING_OFFSET_5MS)
#define WINDOW_SIZE (FRAME_SIZE + OVERLAP_SIZE)
#define FREQ_SIZE (WINDOW_SIZE/2 + 1)

#define NB_BANDS 18
#define NB_BANDS_1 (NB_BANDS - 1)

void lpcn_compute_band_energy(float *bandE, const kiss_fft_cpx *X);
void burg_cepstral_analysis(float *ceps, const float *x);

void apply_window(float *x);
void dct(float *out, const float *in);
void forward_transform(kiss_fft_cpx *out, const float *in);
float lpc_from_cepstrum(float *lpc, const float *cepstrum);
void apply_window(float *x);
void lpc_weighting(float *lpc, float gamma);

#endif