libgsmhr1 RxFE: store CN R0+LPC separately from speech In the original GSM 06.06 code the ECU for speech mode is entirely separate from the CN generator, maintaining separate state. (The main intertie between them is the speech vs CN state variable, distinguishing between speech and CN BFIs, in addition to the CN-specific function of distinguishing between initial and update SIDs.) In the present RxFE implementation I initially thought that we could use the same saved_frame buffer for both ECU and CN, overwriting just the first 4 params (R0 and LPC) when a valid SID comes in. However, I now realize it was a bad idea: the original code has a corner case (long sequence of speech-mode BFIs to put the ECU in state 6, then SID and CN-mode BFIs, then a good speech frame) that would be broken by that buffer reuse approach. We could eliminate this corner case by resetting the ECU state when passing through a CN insertion period, but doing so would needlessly increase the behavioral diffs between GSM 06.06 and our version. Solution: use a separate CN-specific buffer for CN R0+LPC parameters, and match the behavior of GSM 06.06 code in this regard.

/*
 * This header file provides prototype declarations for AMR IF1
 * packing and unpacking functions, as well as extern declarations
 * for the set of const data tables they need.
 */

#ifndef	if1_func_h
#define	if1_func_h

#include <stdint.h>
#include "tw_amr.h"
#include "typedef.h"

void if1_pack_bytes(enum Mode mode, const Word16 *serial_bits,
		    uint8_t *if1_bytes);
void if1_unpack_bytes(enum Mode mode, const uint8_t *if1_bytes,
		      Word16 *serial_bits);

extern const uint8_t sort_475[95];
extern const uint8_t sort_515[103];
extern const uint8_t sort_59[118];
extern const uint8_t sort_67[134];
extern const uint8_t sort_74[148];
extern const uint8_t sort_795[159];
extern const uint8_t sort_102[204];
extern const uint8_t sort_122[244];

#endif	/* include guard */