diff options
| -rw-r--r-- | include/osmocom/msc/codec_sdp_cc_t9n.h | 3 | ||||
| -rw-r--r-- | src/libmsc/codec_sdp_cc_t9n.c | 56 |
2 files changed, 59 insertions, 0 deletions
diff --git a/include/osmocom/msc/codec_sdp_cc_t9n.h b/include/osmocom/msc/codec_sdp_cc_t9n.h index 8f91c788b..8993eb291 100644 --- a/include/osmocom/msc/codec_sdp_cc_t9n.h +++ b/include/osmocom/msc/codec_sdp_cc_t9n.h @@ -50,6 +50,9 @@ const struct codec_mapping *codec_mapping_by_perm_speech(enum gsm0808_permitted_ const struct codec_mapping *codec_mapping_by_subtype_name(const char *subtype_name); const struct codec_mapping *codec_mapping_by_mgcp_codec(enum mgcp_codecs mgcp); +int amr_fmtp_from_gsm0808_speech_codec(char *buf, size_t buflen, const struct gsm0808_speech_codec *sc); +int amr_fmtp_to_gsm0808_speech_codec(struct gsm0808_speech_codec *sc, const char *fmtp); + int bearer_cap_add_speech_ver(struct gsm_mncc_bearer_cap *bearer_cap, enum gsm48_bcap_speech_ver speech_ver); int sdp_audio_codec_add_to_bearer_cap(struct gsm_mncc_bearer_cap *bearer_cap, const struct sdp_audio_codec *codec); int sdp_audio_codecs_to_bearer_cap(struct gsm_mncc_bearer_cap *bearer_cap, const struct sdp_audio_codecs *ac); diff --git a/src/libmsc/codec_sdp_cc_t9n.c b/src/libmsc/codec_sdp_cc_t9n.c index 790202c0e..aa83112b9 100644 --- a/src/libmsc/codec_sdp_cc_t9n.c +++ b/src/libmsc/codec_sdp_cc_t9n.c @@ -284,6 +284,62 @@ const struct codec_mapping *codec_mapping_by_mgcp_codec(enum mgcp_codecs mgcp) return NULL; } +/* Return a bitmask of active AMR rates given the speec codec config nr, i.e. the column nr in 3GPP TS 28.062, Table + * 7.11.3.1.3-2, a.k.a. S0-S15. The full_rate flag is needed because config nr 1 is special: it includes 12.2k on FR but + * excludes it on HR. Iff full_rate == true, 12.2k is included for sc_cfg_nr == 1. */ +uint8_t amr_rates_from_speech_codec_cfg_nr(uint8_t sc_cfg_nr, bool full_rate) +{ +#define B(BIT) (1 << (BIT)) +#define RATE_4_75 B(0) +#define RATE_5_15 B(1) +#define RATE_5_90 B(2) +#define RATE_6_70 B(3) +#define RATE_7_40 B(4) +#define RATE_7_95 B(5) +#define RATE_10_2 B(6) +#define RATE_12_2 B(7) + static const uint8_t _amr_rates_from_speech_codec_cfg_nr[] = { + [0] = RATE_4_75, + [1] = RATE_4_75 | RATE_5_90 | RATE_7_40 | RATE_12_2, + [2] = RATE_5_90, + [3] = RATE_6_70, + [4] = RATE_7_40, + [5] = RATE_7_95, + [6] = RATE_10_2, + [7] = RATE_12_2, + [8] = RATE_4_75 | RATE_5_90, + [9] = RATE_4_75 | RATE_5_90 | RATE_6_70, + [10] = RATE_4_75 | RATE_5_90 | RATE_6_70 | RATE_7_40, + [11] = RATE_4_75 | RATE_5_90 | RATE_6_70 | RATE_7_40, + [12] = RATE_4_75 | RATE_5_90 | RATE_6_70 | RATE_10_2, + [13] = RATE_4_75 | RATE_5_90 | RATE_6_70 | RATE_10_2, + [14] = RATE_4_75 | RATE_5_90 | RATE_7_95 | RATE_12_2, + [15] = RATE_4_75 | RATE_5_90 | RATE_7_95 | RATE_12_2, + }; + uint8_t ret; + OSMO_ASSERT(sc_cfg_nr < ARRAY_SIZE(_amr_rates_from_speech_codec_cfg_nr)); + ret = _amr_rates_from_speech_codec_cfg_nr[sc_cfg_nr]; + if (!full_rate && sc_cfg_nr == 1) + ret &= ~RATE_12_2; + return ret; +} + +int amr_fmtp_from_gsm0808_speech_codec(char *buf, size_t buflen, const struct gsm0808_speech_codec *sc) +{ + struct osmo_strbuf sb = { .buf = buf, .len = buflen }; + + /* 3GPP TS 26.103 says "The bandwidth efficient mode of RFC 4867 shall be used. To offer the bandwidth-efficient + * mode, the octet-align parameter should be omitted in SDP." So never include 'octet-align=1'. + */ + + /* Accumulate rates that are allowed by the cfg bits */ + uint8_t mode_sets = 0; +} + +int amr_fmtp_to_gsm0808_speech_codec(struct gsm0808_speech_codec *sc, const char *fmtp) +{ +} + /* Append given Speech Version to the end of the Bearer Capabilities Speech Version array. Return 1 if added, zero * otherwise (as in, return the number of items added). */ int bearer_cap_add_speech_ver(struct gsm_mncc_bearer_cap *bearer_cap, enum gsm48_bcap_speech_ver speech_ver) |