codec.h File Reference

#include <stdint.h>
#include <stdbool.h>
#include <osmocom/core/utils.h>

Go to the source code of this file.

Enumerations
enum	osmo_amr_type {   AMR_4_75 = 0,   AMR_5_15 = 1,   AMR_5_90 = 2,   AMR_6_70 = 3,   AMR_7_40 = 4,   AMR_7_95 = 5,   AMR_10_2 = 6,   AMR_12_2 = 7,   AMR_SID = 8,   AMR_GSM_EFR_SID = 9,   AMR_TDMA_EFR_SID = 10,   AMR_PDC_EFR_SID = 11,   AMR_NO_DATA = 15 }
enum	osmo_amr_quality {   AMR_BAD = 0,   AMR_GOOD = 1 }

Functions
static bool	osmo_amr_is_speech (enum osmo_amr_type ft)
	Check if given AMR Frame Type is a speech frame. More...
bool	osmo_fr_check_sid (const uint8_t *rtp_payload, size_t payload_len)
	Check whether RTP frame contains FR SID code word according to TS 101 318 §5.1.2. More...
bool	osmo_hr_check_sid (const uint8_t *rtp_payload, size_t payload_len)
	Check whether RTP frame contains HR SID code word according to TS 101 318 §5.2.2. More...
int	osmo_amr_rtp_enc (uint8_t *payload, uint8_t cmr, enum osmo_amr_type ft, enum osmo_amr_quality bfi)
	Encode various AMR parameters from RTP payload (RFC 4867) More...
int	osmo_amr_rtp_dec (const uint8_t *payload, int payload_len, uint8_t *cmr, int8_t *cmi, enum osmo_amr_type *ft, enum osmo_amr_quality *bfi, int8_t *sti)
	Decode various AMR parameters from RTP payload (RFC 4867) acording to 3GPP TS 26.101. More...

Variables
const uint16_t	gsm610_bitorder []
const uint16_t	gsm620_unvoiced_bitorder []
const uint16_t	gsm620_voiced_bitorder []
const uint16_t	gsm660_bitorder []
const uint16_t	gsm690_12_2_bitorder []
const uint16_t	gsm690_10_2_bitorder []
const uint16_t	gsm690_7_95_bitorder []
const uint16_t	gsm690_7_4_bitorder []
const uint16_t	gsm690_6_7_bitorder []
const uint16_t	gsm690_5_9_bitorder []
const uint16_t	gsm690_5_15_bitorder []
const uint16_t	gsm690_4_75_bitorder []
const struct value_string	osmo_amr_type_names []

Enumeration Type Documentation

osmo_amr_quality

enum osmo_amr_quality

Enumerator
AMR_BAD
AMR_GOOD

osmo_amr_type

enum osmo_amr_type

Enumerator
AMR_4_75
AMR_5_15
AMR_5_90
AMR_6_70
AMR_7_40
AMR_7_95
AMR_10_2
AMR_12_2
AMR_SID
AMR_GSM_EFR_SID
AMR_TDMA_EFR_SID
AMR_PDC_EFR_SID
AMR_NO_DATA

Function Documentation

osmo_amr_is_speech()

static bool osmo_amr_is_speech ( enum osmo_amr_type  ft )

inlinestatic

Check if given AMR Frame Type is a speech frame.

Parameters

[in]

ft

AMR Frame Type

Returns

true if AMR with given Frame Type contains voice, false otherwise

References AMR_10_2, AMR_12_2, AMR_4_75, AMR_5_15, AMR_5_90, AMR_6_70, AMR_7_40, AMR_7_95, osmo_amr_rtp_dec(), osmo_amr_rtp_enc(), osmo_fr_check_sid(), and osmo_hr_check_sid().

osmo_amr_rtp_dec()

int osmo_amr_rtp_dec	(	const uint8_t *	rtppayload,
		int	payload_len,
		uint8_t *	cmr,
		int8_t *	cmi,
		enum osmo_amr_type *	ft,
		enum osmo_amr_quality *	bfi,
		int8_t *	sti
	)

Decode various AMR parameters from RTP payload (RFC 4867) acording to 3GPP TS 26.101.

Parameters

[in]	rtppayload	Payload from RTP packet
[in]	payload_len	length of rtppayload
[out]	cmr	AMR Codec Mode Request, not filled if NULL
[out]	cmi	AMR Codec Mode Indicator, -1 if not applicable for this type, not filled if NULL
[out]	ft	AMR Frame Type, not filled if NULL
[out]	bfi	AMR Bad Frame Indicator, not filled if NULL
[out]	sti	AMR SID Type Indicator, -1 if not applicable for this type, not filled if NULL

Returns

length of AMR data or negative value on error

References amr_len_by_ft, and AMR_SID.

Referenced by osmo_amr_is_speech().

osmo_amr_rtp_enc()

int osmo_amr_rtp_enc	(	uint8_t *	payload,
		uint8_t	cmr,
		enum osmo_amr_type	ft,
		enum osmo_amr_quality	bfi
	)

Encode various AMR parameters from RTP payload (RFC 4867)

Parameters

[out]	payload	Payload for RTP packet, contains speech data (if any) except for have 2 first bytes where header will be built
[in]	cmr	AMR codec Mode Request
[in]	ft	AMR Frame Type
[in]	bfi	AMR Bad Frame Indicator

Returns

length of AMR data (header + ToC + speech data) or negative value on error

Note: only octet-aligned mode is supported so the header occupies 2 full bytes. Optional interleaving header is not supported.

References amr_len_by_ft.

Referenced by osmo_amr_is_speech().

osmo_fr_check_sid()

bool osmo_fr_check_sid	(	const uint8_t *	rtp_payload,
		size_t	payload_len
	)

Check whether RTP frame contains FR SID code word according to TS 101 318 §5.1.2.

Parameters

[in]	rtp_payload	Buffer with RTP payload
[in]	payload_len	Length of payload

Returns

true if code word is found, false otherwise

Referenced by osmo_amr_is_speech().

osmo_hr_check_sid()

bool osmo_hr_check_sid	(	const uint8_t *	rtp_payload,
		size_t	payload_len
	)

Check whether RTP frame contains HR SID code word according to TS 101 318 §5.2.2.

Parameters

[in]	rtp_payload	Buffer with RTP payload
[in]	payload_len	Length of payload

Returns

true if code word is found, false otherwise

References mask().

Referenced by osmo_amr_is_speech().

Variable Documentation

gsm610_bitorder

const uint16_t gsm610_bitorder[]

gsm620_unvoiced_bitorder

const uint16_t gsm620_unvoiced_bitorder[]

gsm620_voiced_bitorder

const uint16_t gsm620_voiced_bitorder[]

gsm660_bitorder

const uint16_t gsm660_bitorder[]

gsm690_10_2_bitorder

const uint16_t gsm690_10_2_bitorder[]

gsm690_12_2_bitorder

const uint16_t gsm690_12_2_bitorder[]

gsm690_4_75_bitorder

const uint16_t gsm690_4_75_bitorder[]

gsm690_5_15_bitorder

const uint16_t gsm690_5_15_bitorder[]

gsm690_5_9_bitorder

const uint16_t gsm690_5_9_bitorder[]

gsm690_6_7_bitorder

const uint16_t gsm690_6_7_bitorder[]

gsm690_7_4_bitorder

const uint16_t gsm690_7_4_bitorder[]

gsm690_7_95_bitorder

const uint16_t gsm690_7_95_bitorder[]

osmo_amr_type_names

const struct value_string osmo_amr_type_names[]