libosmo-netif 1.6.0.202502162026
Osmocom network interface library
amr.h
1#ifndef _OSMO_AMR_H_
2#define _OSMO_AMR_H_
3
4#include <stddef.h>
5#include <stdbool.h>
6#include <stdint.h>
7
8#include <osmocom/core/endian.h>
9
10/* As defined by RFC3267: Adaptive Multi-Rate (AMR) */
11
12/*
13 * +----------------+-------------------+----------------
14 * | payload header | table of contents | speech data ...
15 * +----------------+-------------------+----------------
16 */
17
18/*
19 * 4.3. Bandwidth-Efficient Mode:
20 *
21 * Summary from 4.3.4: Same as Octet aligned (see below) but without padding after header and ToC:
22 * 0 1
23 * 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7
24 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
25 * | CMR |F| FT |Q|X X X X X X|
26 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
27 *
28 * X means AMR payload (padding in case of FT=NO_DATA).
29 */
30struct amr_hdr_bwe {
31#if OSMO_IS_LITTLE_ENDIAN
32 uint8_t ft_hi:3, /* coding mode highest part */
33 f:1,
34 cmr:4; /* Codec Mode Request */
35 uint8_t data_start:6,
36 q:1, /* OK (not damaged) at origin? */
37 ft_lo:1; /* coding mode lowest bit */
38#elif OSMO_IS_BIG_ENDIAN
39/* auto-generated from the little endian part above (libosmocore/contrib/struct_endianness.py) */
40 uint8_t cmr:4, f:1, ft_hi:3;
41 uint8_t ft_lo:1, q:1, data_start:6;
42#endif
43 uint8_t data[0];
44} __attribute__((packed));
45
46/* See diagram above: CMR (4) + F (1) + FT (4) + Q (1) = 10 */
47#define AMR_HDR_BWE_LEN_BITS 10
48
49/*
50 * 4.4. Octet-aligned Mode:
51 *
52 * 4.4.1. The Payload Header:
53 *
54 * 0 1 2 3 4 5 6 7
55 * +-+-+-+-+-+-+-+-+
56 * | CMR |X X X X|
57 * +-+-+-+-+-+-+-+-+
58 *
59 * According to: 3GPP TS 26.201 "AMR Wideband speech codec; Frame Structure",
60 * version 5.0.0 (2001-03), 3rd Generation Partnership Project (3GPP):
61 *
62 * Possible Frame type / CMR values:
63 *
64 * 0-8 for AMR-WB (from 6.60 kbit/s to 23.85 kbit/s)
65 * 9 (SID) confort noise.
66 * 10-13 future use.
67 * 14 means lost speech frame (only available for AMR-WB)
68 * 15 means no data
69 *
70 * 4.4.2. The table of contents:
71 *
72 * 0 1 2 3 4 5 6 7
73 * +-+-+-+-+-+-+-+-+
74 * |F| FT |Q|X X|
75 * +-+-+-+-+-+-+-+-+
76 *
77 * X means padding.
78 */
79
80struct amr_hdr {
81#if OSMO_IS_LITTLE_ENDIAN
82 /* Payload Header */
83 uint8_t pad1:4,
84 cmr:4; /* Codec Mode Request */
85 /* Table of Contents */
86 uint8_t pad2:2,
87 q:1, /* OK (not damaged) at origin? */
88 ft:4, /* coding mode */
89 f:1; /* followed by another speech frame? */
90#elif OSMO_IS_BIG_ENDIAN
91/* auto-generated from the little endian part above (libosmocore/contrib/struct_endianness.py) */
92 uint8_t cmr:4, pad1:4;
93 uint8_t f:1, ft:4, q:1, pad2:2;
94#endif
95 uint8_t data[0];
96} __attribute__((packed));
97
98static inline void *osmo_amr_get_payload(struct amr_hdr *amrh)
99{
100 return (uint8_t *)amrh + sizeof(struct amr_hdr);
101}
102
103/* AMR voice frame type identifiers
104 * See also 3GPP TS 26.101, Table 1a: Interpretation of Frame Type, Mode
105 * Indication and Mode Request fields */
106#define AMR_FT_0 0 /* 4.75 */
107#define AMR_FT_1 1 /* 5.15 */
108#define AMR_FT_2 2 /* 5.90 */
109#define AMR_FT_3 3 /* 6.70 */
110#define AMR_FT_4 4 /* 7.40 */
111#define AMR_FT_5 5 /* 7.95 */
112#define AMR_FT_6 6 /* 10.2 */
113#define AMR_FT_7 7 /* 12.2 */
114#define AMR_FT_SID 8 /* AMR SID */
115#define AMR_FT_GSM_EFR_SID 9 /* GSM-EFR SID */
116#define AMR_FT_TDMA_EFR_SID 10 /* TDMA-EFR SID */
117#define AMR_FT_PDC_EFR_SID 11 /* PDC-EFR SID */
118/* version 16.0.0 Release 16: 12-14 for future use */
119#define AMR_FT_NO_DATA 15 /* NO_DATA */
120#define AMR_FT_MAX 16 /* INTERNAL, NO NOT USE OUTSIDE libosmo-netif */
121
122/* AMR voice frame length (in bits).
123 * See also RFC 3267, chapter 3.6.
124 *
125 * NOTE: These constants refer to the length of one AMR speech frame-block,
126 * not counting CMR, TOC. */
127#define AMR_FT_0_LEN_BITS 95 /* 4.75 */
128#define AMR_FT_1_LEN_BITS 103 /* 5.15 */
129#define AMR_FT_2_LEN_BITS 118 /* 5.90 */
130#define AMR_FT_3_LEN_BITS 134 /* 6.70 */
131#define AMR_FT_4_LEN_BITS 148 /* 7.40 */
132#define AMR_FT_5_LEN_BITS 159 /* 7.95 */
133#define AMR_FT_6_LEN_BITS 204 /* 10.2 */
134#define AMR_FT_7_LEN_BITS 244 /* 12.2 */
135#define AMR_FT_SID_LEN_BITS 39 /* SID */
136#define AMR_FT_GSM_EFR_SID_LEN_BITS 43 /* GSM-EFR SID */
137#define AMR_FT_TDMA_EFR_SID_LEN_BITS 38 /* TDMA-EFR SID */
138#define AMR_FT_PDC_EFR_SID_LEN_BITS 37 /* PDC-EFR SID */
139/* version 16.0.0 Release 16: 12-14 for future use */
140#define AMR_FT_NO_DATA_LEN_BITS 0 /* NO_DATA */
141
142/* AMR voice frame length (in bytes, rounded).
143 *
144 * NOTE: These constants refer to the length of one AMR speech frame-block,
145 * not counting CMR, TOC. */
146#define AMR_FT_0_LEN ((AMR_FT_0_LEN_BITS+7)/8) /* 4.75 */
147#define AMR_FT_1_LEN ((AMR_FT_1_LEN_BITS+7)/8) /* 5.15 */
148#define AMR_FT_2_LEN ((AMR_FT_2_LEN_BITS+7)/8) /* 5.90 */
149#define AMR_FT_3_LEN ((AMR_FT_3_LEN_BITS+7)/8) /* 6.70 */
150#define AMR_FT_4_LEN ((AMR_FT_4_LEN_BITS+7)/8) /* 7.40 */
151#define AMR_FT_5_LEN ((AMR_FT_5_LEN_BITS+7)/8) /* 7.95 */
152#define AMR_FT_6_LEN ((AMR_FT_6_LEN_BITS+7)/8) /* 10.2 */
153#define AMR_FT_7_LEN ((AMR_FT_7_LEN_BITS+7)/8) /* 12.2 */
154#define AMR_FT_SID_LEN ((AMR_FT_SID_LEN_BITS+7)/8) /* SID */
155#define AMR_FT_GSM_EFR_SID_LEN ((AMR_FT_GSM_EFR_SID_LEN_BITS+7)/8) /* GSM-EFR SID */
156#define AMR_FT_TDMA_EFR_SID_LEN ((AMR_FT_TDMA_EFR_SID_LEN_BITS+7)/8) /* TDMA-EFR SID */
157#define AMR_FT_PDC_EFR_SID_LEN ((AMR_FT_PDC_EFR_SID_LEN_BITS+7)/8) /* PDC-EFR SID */
158/* version 16.0.0 Release 16: 12-14 for future use */
159#define AMR_FT_NO_DATA_LEN ((AMR_FT_NO_DATA_LEN_BITS+7)/8) /* NO_DATA */
160
161int osmo_amr_ft_valid(uint8_t amr_ft);
162size_t osmo_amr_bytes(uint8_t amr_cmr);
163size_t osmo_amr_bits(uint8_t amr_ft);
164
165bool osmo_amr_is_oa(const uint8_t *payload, unsigned int payload_len);
166int osmo_amr_oa_to_bwe(uint8_t *payload, unsigned int payload_len);
167int osmo_amr_bwe_to_oa(uint8_t *payload, unsigned int payload_len,
168 unsigned int payload_maxlen);
169int osmo_amr_bwe_to_iuup(uint8_t *payload, unsigned int payload_len);
170int osmo_amr_iuup_to_bwe(uint8_t *payload, unsigned int payload_len,
171 unsigned int payload_maxlen);
172int osmo_amr_bytes_to_ft(size_t bytes);
173
174#endif
amr_hdr_bwe
Definition: amr.h:30
amr_hdr
Definition: amr.h:80