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view libgsmfrp/gsm_fr_preproc.h @ 183:452c1d5a6268

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libgsmefr BFI w/o data: emit zero output after decoder reset In real-life usage, each EFR decoder session will most likely begin with lots of BFI frames before the first real frame arrives. However, because the spec-defined home state of the decoder is speech rather than CN, our regular logic for BFI w/o data would have to feed pseudorandom noise to the decoder (in the "fixed codebook excitation pulses" part), which is silly to do at the beginning of the decoder session right out of reset. Therefore, let's check reset_flag_old, and if we are still in the reset state, simply emit zero output.
author Mychaela Falconia <falcon@freecalypso.org>
date Tue, 03 Jan 2023 00:12:18 +0000
parents 2b5770c715ee
children
line wrap: on
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/*
 * This header file is the external public interface to libgsmfrp;
 * it should be installed in the same system include directory
 * as <gsm.h> from libgsm, on which we depend.
 */

#ifndef	__GSM_FR_PREPROC_H
#define	__GSM_FR_PREPROC_H

#include <gsm.h>

struct gsmfr_preproc_state;	/* opaque to external users */

extern struct gsmfr_preproc_state *gsmfr_preproc_create(void);
/* use standard free() call to free it afterward */

/* reset state to initial */
extern void gsmfr_preproc_reset(struct gsmfr_preproc_state *state);

/* main processing functions */
extern void gsmfr_preproc_good_frame(struct gsmfr_preproc_state *state,
				     gsm_byte *frame);
extern void gsmfr_preproc_bfi(struct gsmfr_preproc_state *state, int taf,
			      gsm_byte *frame_out);

/* utility function */
extern int gsmfr_preproc_sid_classify(const gsm_byte *frame);

/* utility datum */
extern const gsm_frame gsmfr_preproc_silence_frame;

#endif	/* include guard */