FreeCalypso > hg > gsm-codec-lib
view libtwamr/if1_unpack.c @ 479:616b7ba1135b
doc/AMR-library-API: document AMR-EFR hybrid decoder
author | Mychaela Falconia <falcon@freecalypso.org> |
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date | Sun, 19 May 2024 22:22:40 +0000 |
parents | ebe499058c63 |
children |
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/* * In this module we implement our function for unpacking bits from AMR IF1 * and reshuffling them into the codec's natural bit order. */ #include <stdint.h> #include "tw_amr.h" #include "typedef.h" #include "namespace.h" #include "int_defs.h" #include "if1_func.h" static inline Word16 msb_get_bit(const uint8_t *buf, Word16 bn) { Word16 pos_byte = bn >> 3; Word16 pos_bit = 7 - (bn & 7); return (buf[pos_byte] >> pos_bit) & 1; } static void unpack_bits(const uint8_t *if1_bytes, Word16 *codec_bits, Word16 nbits, const uint8_t *table) { Word16 n, nb; for (n = 0; n < nbits; n++) { if (table) nb = table[n]; else nb = n; codec_bits[nb] = msb_get_bit(if1_bytes, n); } } void if1_unpack_bytes(enum Mode mode, const uint8_t *if1_bytes, Word16 *serial_bits) { switch (mode) { case MR475: unpack_bits(if1_bytes, serial_bits, AMR_NBITS_475, sort_475); return; case MR515: unpack_bits(if1_bytes, serial_bits, AMR_NBITS_515, sort_515); return; case MR59: unpack_bits(if1_bytes, serial_bits, AMR_NBITS_59, sort_59); return; case MR67: unpack_bits(if1_bytes, serial_bits, AMR_NBITS_67, sort_67); return; case MR74: unpack_bits(if1_bytes, serial_bits, AMR_NBITS_74, sort_74); return; case MR795: unpack_bits(if1_bytes, serial_bits, AMR_NBITS_795, sort_795); return; case MR102: unpack_bits(if1_bytes, serial_bits, AMR_NBITS_102, sort_102); return; case MR122: unpack_bits(if1_bytes, serial_bits, AMR_NBITS_122, sort_122); return; case MRDTX: unpack_bits(if1_bytes, serial_bits, AMR_NBITS_SID, (const uint8_t *) 0); return; } }