view libgsmfrp/internal.h @ 282:9ee8ad3d4d30

frtest: rm gsmfr-hand-test and gsmfr-max-out utils These hack programs were never properly documented and were written only as part of a debug chase, in pursuit of a bug that ultimately turned out to be in our then-hacky patch to osmo-bts-sysmo, before beginning of proper patches in Osmocom. These hack programs need to be dropped from the present sw package because they depend on old libgsm, and we are eliminating that dependency.
author Mychaela Falconia <falcon@freecalypso.org>
date Sun, 14 Apr 2024 05:44:47 +0000
parents 6ac547f0b903
children
line wrap: on
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/*
 * This header file is internal to libgsmfrp;
 * here we define our state structure.
 */

enum rx_state {
	NO_DATA = 0,
	SPEECH,
	SPEECH_MUTING,
	COMFORT_NOISE,
	LOST_SID,
	CN_MUTING,
};

struct gsmfr_preproc_state {
	enum rx_state	rx_state;
	gsm_frame	speech_frame;
	gsm_byte	sid_prefix[5];
	uint8_t		sid_xmaxc;
	uint32_t	cn_random_lfsr;
	unsigned	cn_random_6fold;
};

/* we use the same LFSR PRNG for CN as ETSI EFR implementation */
#define PN_INITIAL_SEED 0x70816958L   /* Pseudo noise generator seed value  */

/* internal functions */
extern void gsmfr_preproc_gen_cn(struct gsmfr_preproc_state *state,
				 gsm_byte *frame);
extern void gsmfr_preproc_sid2cn(struct gsmfr_preproc_state *state,
				 gsm_byte *frame);
extern void gsmfr_preproc_invalid_sid(struct gsmfr_preproc_state *state,
				      gsm_byte *frame);
extern uint16_t gsmfr_preproc_prng(struct gsmfr_preproc_state *state,
				   uint16_t no_bits);
extern uint8_t gsmfr_preproc_xmaxc_mean(const gsm_byte *frame);