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view libtwamr/if1_func.h @ 604:54f0f1b74c25

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libgsmhr1 TFO: require BFI=0 and SID=0 for homing In order for a received frame to be recognized as DHF, we need not only the correct bit pattern, but also BFI=0 and SID=0. The BFI=0 requirement should be obvious, while the SID=0 requirement is needed only for HR codec. With FR and EFR, SID classification comes from the payload bits and no separate check is needed - but in HR we get an out-of-band SID ternary flag. When SID=1, no payload bits are used at all; when SID=2, we use only the first 33 bits of the payload. Therefore, it is proper to conditionalize DHF acceptance on SID=0. We already implemented this logic in the just finished full decoder; now bring TFO code into agreement.
author Mychaela Falconia <falcon@freecalypso.org>
date Thu, 04 Dec 2025 19:40:35 +0000
parents ebe499058c63
children
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line source

/*
 * 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 */