comparison libtwamr/if1_pack.c @ 441:ebe499058c63

libtwamr: implement API functions for RFC 4867 I/O
author Mychaela Falconia <falcon@freecalypso.org>
date Thu, 09 May 2024 07:06:31 +0000
parents amrconv/if1_pack.c@4c4649a5fec3
children
comparison
equal deleted inserted replaced
440:bc736a8654af 441:ebe499058c63
1 /*
2 * In this module we implement our function for packing AMR codec bits
3 * from an array containing them in the codec's natural bit order
4 * into the octet form of AMR IF1 and RFC 4867.
5 */
6
7 #include <stdint.h>
8 #include "tw_amr.h"
9 #include "typedef.h"
10 #include "namespace.h"
11 #include "int_defs.h"
12 #include "if1_func.h"
13
14 static inline void msb_set_bit(uint8_t *buf, Word16 bn, Word16 bit)
15 {
16 Word16 pos_byte = bn >> 3;
17 Word16 pos_bit = 7 - (bn & 7);
18
19 if (bit)
20 buf[pos_byte] |= (1 << pos_bit);
21 else
22 buf[pos_byte] &= ~(1 << pos_bit);
23 }
24
25 static void pack_bits(uint8_t *if1_bytes, const Word16 *src_bits, Word16 nbits,
26 const uint8_t *table)
27 {
28 Word16 n, nb;
29
30 for (n = 0; n < nbits; n++) {
31 if (table)
32 nb = table[n];
33 else
34 nb = n;
35 msb_set_bit(if1_bytes, n, src_bits[nb]);
36 }
37 }
38
39 void if1_pack_bytes(enum Mode mode, const Word16 *serial_bits,
40 uint8_t *if1_bytes)
41 {
42 switch (mode) {
43 case MR475:
44 pack_bits(if1_bytes, serial_bits, AMR_NBITS_475, sort_475);
45 if1_bytes[11] &= 0xFE;
46 return;
47 case MR515:
48 pack_bits(if1_bytes, serial_bits, AMR_NBITS_515, sort_515);
49 if1_bytes[12] &= 0xFE;
50 return;
51 case MR59:
52 pack_bits(if1_bytes, serial_bits, AMR_NBITS_59, sort_59);
53 if1_bytes[14] &= 0xFC;
54 return;
55 case MR67:
56 pack_bits(if1_bytes, serial_bits, AMR_NBITS_67, sort_67);
57 if1_bytes[16] &= 0xFC;
58 return;
59 case MR74:
60 pack_bits(if1_bytes, serial_bits, AMR_NBITS_74, sort_74);
61 if1_bytes[18] &= 0xF0;
62 return;
63 case MR795:
64 pack_bits(if1_bytes, serial_bits, AMR_NBITS_795, sort_795);
65 if1_bytes[19] &= 0xFE;
66 return;
67 case MR102:
68 pack_bits(if1_bytes, serial_bits, AMR_NBITS_102, sort_102);
69 if1_bytes[25] &= 0xF0;
70 return;
71 case MR122:
72 pack_bits(if1_bytes, serial_bits, AMR_NBITS_122, sort_122);
73 if1_bytes[30] &= 0xF0;
74 return;
75 case MRDTX:
76 pack_bits(if1_bytes, serial_bits, AMR_NBITS_SID,
77 (const uint8_t *) 0);
78 if1_bytes[4] &= 0xE0;
79 return;
80 }
81 }