gsm-codec-lib: doc/EFR-library-API annotate

annotate doc/EFR-library-API @ 585:3c6bf0d26ee7 default tip

TW-TS-005 reader: fix maximum line length bug TW-TS-005 section 4.1 states: The maximum allowed length of each line is 80 characters, not including the OS-specific newline encoding. The implementation of this line length limit in the TW-TS-005 hex file reader function in the present suite was wrong, such that lines of the full maximum length could not be read. Fix it. Note that this bug affects comment lines too, not just actual RTP payloads. Neither Annex A nor Annex B features an RTP payload format that goes to the maximum of 40 bytes, but if a comment line goes to the maximum allowed length of 80 characters not including the terminating newline, the bug will be triggered, necessitating the present fix.

author	Mychaela Falconia <falcon@freecalypso.org>
date	Tue, 25 Feb 2025 07:49:28 +0000
parents	b07dba7b8a4f
children

rev	line source
463 9208db14b4b9 doc/EFR-library-API: rm reference to old libgsm Mychaela Falconia <falcon@freecalypso.org> parents: 161 diff changeset	1 Libgsmefr general usage
9208db14b4b9 doc/EFR-library-API: rm reference to old libgsm Mychaela Falconia <falcon@freecalypso.org> parents: 161 diff changeset	2 =======================
9208db14b4b9 doc/EFR-library-API: rm reference to old libgsm Mychaela Falconia <falcon@freecalypso.org> parents: 161 diff changeset	3
123 92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	4 The external public interface to Themyscira libgsmefr consists of a single
463 9208db14b4b9 doc/EFR-library-API: rm reference to old libgsm Mychaela Falconia <falcon@freecalypso.org> parents: 161 diff changeset	5 header file <gsm_efr.h>; it should be installed in some system include
9208db14b4b9 doc/EFR-library-API: rm reference to old libgsm Mychaela Falconia <falcon@freecalypso.org> parents: 161 diff changeset	6 directory.
123 92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	7
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	8 The dialect of C we chose for libgsmefr is ANSI C (function prototypes), const
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	9 qualifier is used where appropriate, and the interface is defined in terms of
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	10 <stdint.h> types; <gsm_efr.h> includes <stdint.h>.
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	11
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	12 State allocation and freeing
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	13 ============================
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	14
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	15 In order to use the EFR encoder, you will need to allocate an encoder state
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	16 structure, and to use the EFR decoder, you will need to allocate a decoder state
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	17 structure. The necessary state allocation functions are:
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	18
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	19 extern struct EFR_encoder_state *EFR_encoder_create(int dtx);
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	20 extern struct EFR_decoder_state *EFR_decoder_create(void);
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	21
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	22 struct EFR_encoder_state and struct EFR_decoder_state are opaque structures to
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	23 library users: you only get pointers which you remember and pass around, but
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	24 <gsm_efr.h> does not give you full definitions of these structs. As a library
544 bd32bb1e8dab doc/EFR-library-API: document malloc-alternative provision Mychaela Falconia <falcon@freecalypso.org> parents: 473 diff changeset	25 user, you ordinarily don't even need to know the size of these structs, hence
bd32bb1e8dab doc/EFR-library-API: document malloc-alternative provision Mychaela Falconia <falcon@freecalypso.org> parents: 473 diff changeset	26 the necessary malloc() operation happens inside EFR_encoder_create() and
bd32bb1e8dab doc/EFR-library-API: document malloc-alternative provision Mychaela Falconia <falcon@freecalypso.org> parents: 473 diff changeset	27 EFR_decoder_create(). (But see a later section of this document regarding
bd32bb1e8dab doc/EFR-library-API: document malloc-alternative provision Mychaela Falconia <falcon@freecalypso.org> parents: 473 diff changeset	28 alternative memory allocation schemes.) However, each structure is malloc'ed
bd32bb1e8dab doc/EFR-library-API: document malloc-alternative provision Mychaela Falconia <falcon@freecalypso.org> parents: 473 diff changeset	29 as a single chunk, hence when you are done with it, simply call free() to
bd32bb1e8dab doc/EFR-library-API: document malloc-alternative provision Mychaela Falconia <falcon@freecalypso.org> parents: 473 diff changeset	30 relinquish each encoder or decoder state instance.
123 92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	31
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	32 EFR_encoder_create() and EFR_decoder_create() functions can fail if the malloc()
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	33 call inside fails, in which case the two libgsmefr functions in question return
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	34 NULL.
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	35
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	36 The dtx argument to EFR_encoder_create() is a Boolean flag represented as an
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	37 int; it tells the EFR encoder whether it should operate with DTX enabled (run
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	38 GSM 06.82 VAD and emit SID frames instead of speech frames per GSM 06.81) or DTX
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	39 disabled (skip VAD and always emit speech frames).
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	40
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	41 Using the EFR encoder
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	42 =====================
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	43
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	44 To encode one 20 ms audio frame per EFR, call EFR_encode_frame():
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	45
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	46 extern void EFR_encode_frame(struct EFR_encoder_state st, const int16_t pcm,
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	47 uint8_t frame, int sp, int *vad);
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	48
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	49 You need to provide an encoder state structure allocated earlier with
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	50 EFR_encoder_create(), a block of 160 linear PCM samples, and an output buffer of
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	51 31 bytes (EFR_RTP_FRAME_LEN constant also defined in <gsm_efr.h>) into which the
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	52 encoded EFR frame will be written; the frame format is that defined in ETSI TS
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	53 101 318 for EFR in RTP, including the 0xC signature in the upper nibble of the
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	54 first byte.
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	55
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	56 The last two arguments of type (int *) are optional pointers to extra output
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	57 flags SP and VAD, defined in GSM 06.81 section 5.1.1; either pointer or both of
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	58 them can be NULL if these extra output flags aren't needed. Both of these flags
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	59 are needed in order to test our libgsmefr encoder implementation against
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	60 official ETSI test sequences (GSM 06.54), but they typically aren't needed
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	61 otherwise.
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	62
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	63 Using the EFR decoder
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	64 =====================
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	65
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	66 The main interface to our EFR decoder is this function:
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	67
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	68 extern void EFR_decode_frame(struct EFR_decoder_state st, const uint8_t frame,
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	69 int bfi, int taf, int16_t *pcm);
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	70
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	71 The inputs consist of 244 bits of frame payload (the 4 upper bits of the first
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	72 byte are ignored - there is NO enforcement of 0xC signature in our frame
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	73 decoder) and BFI and TAF flags defined in GSM 06.81 section 6.1.1. Note the
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	74 absence of a SID flag argument: EFR_decode_frame() calls our own utility
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	75 function EFR_sid_classify() to determine SID from the frame itself per the rules
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	76 of GSM 06.81 section 6.1.1.
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	77
161 fe5aceaf51e0 doc/EFR-library-API: document new handling of BFI with no data Mychaela Falconia <falcon@freecalypso.org> parents: 130 diff changeset	78 The canonical EFR decoder always expects frame bits input to be present, even
fe5aceaf51e0 doc/EFR-library-API: document new handling of BFI with no data Mychaela Falconia <falcon@freecalypso.org> parents: 130 diff changeset	79 during BFI condtions! More specifically, if a BFI=1 decoding call comes in when
fe5aceaf51e0 doc/EFR-library-API: document new handling of BFI with no data Mychaela Falconia <falcon@freecalypso.org> parents: 130 diff changeset	80 the decoder is in comfort noise generation state (after a SID), then all frame
fe5aceaf51e0 doc/EFR-library-API: document new handling of BFI with no data Mychaela Falconia <falcon@freecalypso.org> parents: 130 diff changeset	81 bits passed along with BFI=1 are ignored as one would naturally expect for
fe5aceaf51e0 doc/EFR-library-API: document new handling of BFI with no data Mychaela Falconia <falcon@freecalypso.org> parents: 130 diff changeset	82 frames that typically aren't transmitted at all - but if a BFI=1 decoding call
fe5aceaf51e0 doc/EFR-library-API: document new handling of BFI with no data Mychaela Falconia <falcon@freecalypso.org> parents: 130 diff changeset	83 comes in when the decoder is in regular speech mode, the canonical decoder will
fe5aceaf51e0 doc/EFR-library-API: document new handling of BFI with no data Mychaela Falconia <falcon@freecalypso.org> parents: 130 diff changeset	84 use the "fixed codebook excitation pulses" part of the erroneous frame (one
fe5aceaf51e0 doc/EFR-library-API: document new handling of BFI with no data Mychaela Falconia <falcon@freecalypso.org> parents: 130 diff changeset	85 declared to be garbage) as part of its decoding operation! (This part
fe5aceaf51e0 doc/EFR-library-API: document new handling of BFI with no data Mychaela Falconia <falcon@freecalypso.org> parents: 130 diff changeset	86 constitutes 35 bits per subframe or 140 bits out of 244 per frame.)
fe5aceaf51e0 doc/EFR-library-API: document new handling of BFI with no data Mychaela Falconia <falcon@freecalypso.org> parents: 130 diff changeset	87
fe5aceaf51e0 doc/EFR-library-API: document new handling of BFI with no data Mychaela Falconia <falcon@freecalypso.org> parents: 130 diff changeset	88 BFI with no data
fe5aceaf51e0 doc/EFR-library-API: document new handling of BFI with no data Mychaela Falconia <falcon@freecalypso.org> parents: 130 diff changeset	89 ================
fe5aceaf51e0 doc/EFR-library-API: document new handling of BFI with no data Mychaela Falconia <falcon@freecalypso.org> parents: 130 diff changeset	90
fe5aceaf51e0 doc/EFR-library-API: document new handling of BFI with no data Mychaela Falconia <falcon@freecalypso.org> parents: 130 diff changeset	91 Many EFR decoder applications will be faced with a situation where they receive
fe5aceaf51e0 doc/EFR-library-API: document new handling of BFI with no data Mychaela Falconia <falcon@freecalypso.org> parents: 130 diff changeset	92 a frame gap (no data at all), and they need to run the EFR decoder with BFI=1 -
fe5aceaf51e0 doc/EFR-library-API: document new handling of BFI with no data Mychaela Falconia <falcon@freecalypso.org> parents: 130 diff changeset	93 but the application doesn't have any frame-bits input. Yet the canonical EFR
fe5aceaf51e0 doc/EFR-library-API: document new handling of BFI with no data Mychaela Falconia <falcon@freecalypso.org> parents: 130 diff changeset	94 decoder requires some erroneous frame bits to be fed to it - so what gives?
fe5aceaf51e0 doc/EFR-library-API: document new handling of BFI with no data Mychaela Falconia <falcon@freecalypso.org> parents: 130 diff changeset	95 Our initial approach was to feed the decoder all zeros in the place of codec
fe5aceaf51e0 doc/EFR-library-API: document new handling of BFI with no data Mychaela Falconia <falcon@freecalypso.org> parents: 130 diff changeset	96 parameters - but further analysis reveals that approach to be bad. (To see for
fe5aceaf51e0 doc/EFR-library-API: document new handling of BFI with no data Mychaela Falconia <falcon@freecalypso.org> parents: 130 diff changeset	97 yourself, study the code in d1035pf.c and think what it will do when the input
fe5aceaf51e0 doc/EFR-library-API: document new handling of BFI with no data Mychaela Falconia <falcon@freecalypso.org> parents: 130 diff changeset	98 is fixed at all zeros.) Our new approach is to generate pseudorandom bits for
fe5aceaf51e0 doc/EFR-library-API: document new handling of BFI with no data Mychaela Falconia <falcon@freecalypso.org> parents: 130 diff changeset	99 these pulse parameters, as detailed below.
fe5aceaf51e0 doc/EFR-library-API: document new handling of BFI with no data Mychaela Falconia <falcon@freecalypso.org> parents: 130 diff changeset	100
fe5aceaf51e0 doc/EFR-library-API: document new handling of BFI with no data Mychaela Falconia <falcon@freecalypso.org> parents: 130 diff changeset	101 If you find yourself in the situation of needing to feed BFI=1 with no frame
fe5aceaf51e0 doc/EFR-library-API: document new handling of BFI with no data Mychaela Falconia <falcon@freecalypso.org> parents: 130 diff changeset	102 data bits to the decoder, call the following function in the place of
fe5aceaf51e0 doc/EFR-library-API: document new handling of BFI with no data Mychaela Falconia <falcon@freecalypso.org> parents: 130 diff changeset	103 EFR_decode_frame():
123 92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	104
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	105 extern void EFR_decode_bfi_nodata(struct EFR_decoder_state *st, int taf,
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	106 int16_t *pcm);
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	107
161 fe5aceaf51e0 doc/EFR-library-API: document new handling of BFI with no data Mychaela Falconia <falcon@freecalypso.org> parents: 130 diff changeset	108 This function begins by checking the internal state flag RX_SP_FLAG, indicating
fe5aceaf51e0 doc/EFR-library-API: document new handling of BFI with no data Mychaela Falconia <falcon@freecalypso.org> parents: 130 diff changeset	109 whether the decoder is in speech or comfort noise generation mode. If
fe5aceaf51e0 doc/EFR-library-API: document new handling of BFI with no data Mychaela Falconia <falcon@freecalypso.org> parents: 130 diff changeset	110 RX_SP_FLAG is set, indicating speech state, then the main body of the decoder
fe5aceaf51e0 doc/EFR-library-API: document new handling of BFI with no data Mychaela Falconia <falcon@freecalypso.org> parents: 130 diff changeset	111 will be making use of fixed codebook pulse parameters even for erroneous frames,
fe5aceaf51e0 doc/EFR-library-API: document new handling of BFI with no data Mychaela Falconia <falcon@freecalypso.org> parents: 130 diff changeset	112 and EFR_decode_bfi_nodata() will invoke a PRNG to fill in pseudorandom bits.
fe5aceaf51e0 doc/EFR-library-API: document new handling of BFI with no data Mychaela Falconia <falcon@freecalypso.org> parents: 130 diff changeset	113 If RX_SP_FLAG is clear, then the decoder is generating comfort noise following
fe5aceaf51e0 doc/EFR-library-API: document new handling of BFI with no data Mychaela Falconia <falcon@freecalypso.org> parents: 130 diff changeset	114 reception of a SID, and BFI conditions are fully expected because the
fe5aceaf51e0 doc/EFR-library-API: document new handling of BFI with no data Mychaela Falconia <falcon@freecalypso.org> parents: 130 diff changeset	115 transmitter is expected to be off. In this case EFR_decode_bfi_nodata() feeds
fe5aceaf51e0 doc/EFR-library-API: document new handling of BFI with no data Mychaela Falconia <falcon@freecalypso.org> parents: 130 diff changeset	116 all-zeros parameters to the main body of the decoder, as none of them will be
fe5aceaf51e0 doc/EFR-library-API: document new handling of BFI with no data Mychaela Falconia <falcon@freecalypso.org> parents: 130 diff changeset	117 used.
123 92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	118
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	119 Stateless utility functions
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	120 ===========================
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	121
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	122 All functions in this section are stateless (no encoder state or decoder state
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	123 structure is needed); they merely manipulate bit fields.
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	124
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	125 extern void EFR_frame2params(const uint8_t frame, int16_t params);
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	126
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	127 This function unpacks an EFR codec frame in ETSI TS 101 318 RTP encoding (the
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	128 upper nibble of the first byte is NOT checked, i.e., there is NO enforcement of
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	129 0xC signature) into an array of 57 (EFR_NUM_PARAMS) parameter words for the
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	130 codec. int16_t signed type is used for the params array (even though all
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	131 parameters are actually unsigned) in order to match the guts of ETSI-based EFR
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	132 codec, and EFR_frame2params() is called internally by EFR_decode_frame().
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	133
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	134 extern void EFR_params2frame(const int16_t params, uint8_t frame);
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	135
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	136 This function takes an array of 57 (EFR_NUM_PARAMS) EFR codec parameter words
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	137 and packs them into a 31-byte (EFR_RTP_FRAME_LEN) frame in ETSI TS 101 318
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	138 format. The 0xC signature is generated by this function, and every byte of the
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	139 output buffer is fully written without regard to any previous content. This
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	140 function is called internally by EFR_encode_frame().
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	141
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	142 extern int EFR_sid_classify(const uint8_t *frame);
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	143
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	144 This function analyzes an RTP-encoded EFR frame (the upper nibble of the first
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	145 byte is NOT checked for 0xC signature) for the SID codeword of GSM 06.62 and
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	146 classifies the frame as SID=0, SID=1 or SID=2 per the rules of GSM 06.81
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	147 section 6.1.1.
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	148
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	149 extern void EFR_insert_sid_codeword(uint8_t *frame);
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	150
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	151 This function inserts the SID codeword of GSM 06.62 into the frame in the
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	152 pointed-to buffer; specifically, the 95 bits that make up the SID field are all
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	153 set to 1s, but all other bits remain unchanged. This function is arguably least
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	154 useful to external users of libgsmefr, but it exists because of how the original
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	155 code from ETSI generates SID frames produced by the encoder in DTX mode.
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	156
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	157 Parameter-based encoder and decoder functions
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	158 =============================================
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	159
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	160 The EFR_encode_frame() and EFR_decode_frame() functions described earlier in
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	161 this document constitute the most practically useful (intended for actual use)
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	162 interfaces to our EFR encoder and decoder, but they are actually wrappers around
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	163 these parameter-based functions:
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	164
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	165 extern void EFR_encode_params(struct EFR_encoder_state st, const int16_t pcm,
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	166 int16_t params, int sp, int *vad);
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	167
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	168 This function is similar to EFR_encode_frame(), but the output is an array of
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	169 57 (EFR_NUM_PARAMS) codec parameter words rather than a finished frame. The two
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	170 extra output flags are optional (pointers may be NULL) just like with
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	171 EFR_encode_frame(), but there is a catch: if the output frame is a SID (which
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	172 can only happen if DTX is enabled), the bits inside parameter words that would
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	173 correspond to SID codeword bits are NOT set, instead one MUST call
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	174 EFR_insert_sid_codeword() after packing the frame with EFR_params2frame(). The
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	175 wrapper in EFR_encode_frame() does exactly as described, and the overall logic
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	176 follows the original code structure from ETSI.
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	177
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	178 extern void EFR_decode_params(struct EFR_decoder_state *st,
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	179 const int16_t *params, int bfi, int sid, int taf,
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	180 int16_t *pcm);
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	181
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	182 This function is similar to EFR_decode_frame() with the frame input replaced
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	183 with params array input, but the SID classification per the rules of GSM 06.81
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	184 section 6.1.1 needs to be provided by the caller. The wrapper in
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	185 EFR_decode_frame() calls both EFR_frame2params() and EFR_sid_classify() before
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	186 passing the work to EFR_decode_params().
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	187
545 b07dba7b8a4f doc/EFR-library-API: document RTP input wrapper Mychaela Falconia <falcon@freecalypso.org> parents: 544 diff changeset	188 Decoder RTP input
b07dba7b8a4f doc/EFR-library-API: document RTP input wrapper Mychaela Falconia <falcon@freecalypso.org> parents: 544 diff changeset	189 =================
b07dba7b8a4f doc/EFR-library-API: document RTP input wrapper Mychaela Falconia <falcon@freecalypso.org> parents: 544 diff changeset	190
b07dba7b8a4f doc/EFR-library-API: document RTP input wrapper Mychaela Falconia <falcon@freecalypso.org> parents: 544 diff changeset	191 If a network element is receiving GSM-EFR input via RTP and needs to feed this
b07dba7b8a4f doc/EFR-library-API: document RTP input wrapper Mychaela Falconia <falcon@freecalypso.org> parents: 544 diff changeset	192 input to the decoder, the RTP payload handler needs to support both the basic
b07dba7b8a4f doc/EFR-library-API: document RTP input wrapper Mychaela Falconia <falcon@freecalypso.org> parents: 544 diff changeset	193 RTP format of ETSI TS 101 318 (also RFC 3551) and the extended RTP format of
b07dba7b8a4f doc/EFR-library-API: document RTP input wrapper Mychaela Falconia <falcon@freecalypso.org> parents: 544 diff changeset	194 TW-TS-001. Depending on the format received, and depending on bit flags in the
b07dba7b8a4f doc/EFR-library-API: document RTP input wrapper Mychaela Falconia <falcon@freecalypso.org> parents: 544 diff changeset	195 TEH octet in the case of TW-TS-001, the RTP input handler will need to call
b07dba7b8a4f doc/EFR-library-API: document RTP input wrapper Mychaela Falconia <falcon@freecalypso.org> parents: 544 diff changeset	196 either EFR_decode_frame() or EFR_decode_bfi_nodata() with correct bfi and taf
b07dba7b8a4f doc/EFR-library-API: document RTP input wrapper Mychaela Falconia <falcon@freecalypso.org> parents: 544 diff changeset	197 arguments. Seeing that this complex logic should be abstracted away from
b07dba7b8a4f doc/EFR-library-API: document RTP input wrapper Mychaela Falconia <falcon@freecalypso.org> parents: 544 diff changeset	198 applications into the library, we've added the following wrapper function:
b07dba7b8a4f doc/EFR-library-API: document RTP input wrapper Mychaela Falconia <falcon@freecalypso.org> parents: 544 diff changeset	199
b07dba7b8a4f doc/EFR-library-API: document RTP input wrapper Mychaela Falconia <falcon@freecalypso.org> parents: 544 diff changeset	200 extern int EFR_decode_rtp(struct EFR_decoder_state st, const uint8_t rtp_pl,
b07dba7b8a4f doc/EFR-library-API: document RTP input wrapper Mychaela Falconia <falcon@freecalypso.org> parents: 544 diff changeset	201 unsigned rtp_pl_len, int16_t *pcm);
b07dba7b8a4f doc/EFR-library-API: document RTP input wrapper Mychaela Falconia <falcon@freecalypso.org> parents: 544 diff changeset	202
b07dba7b8a4f doc/EFR-library-API: document RTP input wrapper Mychaela Falconia <falcon@freecalypso.org> parents: 544 diff changeset	203 The semantics and return value of this function are the same as its FRv1
b07dba7b8a4f doc/EFR-library-API: document RTP input wrapper Mychaela Falconia <falcon@freecalypso.org> parents: 544 diff changeset	204 counterpart gsmfr_fulldec_rtp_in(), documented in FR1-library-API article.
b07dba7b8a4f doc/EFR-library-API: document RTP input wrapper Mychaela Falconia <falcon@freecalypso.org> parents: 544 diff changeset	205
123 92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	206 State reset functions
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	207 =====================
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	208
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	209 extern void EFR_encoder_reset(struct EFR_encoder_state *st, int dtx);
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	210 extern void EFR_decoder_reset(struct EFR_decoder_state *st);
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	211
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	212 These functions reset the state of the encoder or the decoder, respectively;
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	213 the entire state structure is fully initialized to the respective home state
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	214 defined in GSM 06.60 section 8.5 for the encoder or section 8.6 for the decoder.
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	215
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	216 EFR_encoder_reset() is called internally by EFR_encoder_create() and by the
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	217 encoder itself when it encounters the ETSI-prescribed encoder homing frame;
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	218 EFR_decoder_reset() is called internally by EFR_decoder_create() and by the
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	219 decoder itself when it encounters the ETSI-prescribed decoder homing frame.
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	220 Therefore, there is generally no need for libgsmefr users to call these
92fdb499b5c3 doc/EFR-library-API article written Mychaela Falconia <falcon@freecalypso.org> parents: diff changeset	221 functions directly - but they are made public for the sake of completeness.
130 1c529bb31219 doc/EFR-library-API: explain dtx argument to EFR_encoder_reset() Mychaela Falconia <falcon@freecalypso.org> parents: 123 diff changeset	222
1c529bb31219 doc/EFR-library-API: explain dtx argument to EFR_encoder_reset() Mychaela Falconia <falcon@freecalypso.org> parents: 123 diff changeset	223 If you call EFR_encoder_reset() manually, you can change the DTX enable/disable
1c529bb31219 doc/EFR-library-API: explain dtx argument to EFR_encoder_reset() Mychaela Falconia <falcon@freecalypso.org> parents: 123 diff changeset	224 flag from its initial value given to EFR_encoder_create() - the new value of
1c529bb31219 doc/EFR-library-API: explain dtx argument to EFR_encoder_reset() Mychaela Falconia <falcon@freecalypso.org> parents: 123 diff changeset	225 this flag passed to EFR_encoder_reset() always takes effect. There is no
1c529bb31219 doc/EFR-library-API: explain dtx argument to EFR_encoder_reset() Mychaela Falconia <falcon@freecalypso.org> parents: 123 diff changeset	226 provision for changing this mode within an encoder session without a full reset.
473 2d46abdfbe91 libgsmefr version 1.1.0 for DHF addition Mychaela Falconia <falcon@freecalypso.org> parents: 463 diff changeset	227
544 bd32bb1e8dab doc/EFR-library-API: document malloc-alternative provision Mychaela Falconia <falcon@freecalypso.org> parents: 473 diff changeset	228 These reset functions may be used to implement an alternative memory allocation
bd32bb1e8dab doc/EFR-library-API: document malloc-alternative provision Mychaela Falconia <falcon@freecalypso.org> parents: 473 diff changeset	229 scheme, if there is a requirement or desire to use something other than plain
bd32bb1e8dab doc/EFR-library-API: document malloc-alternative provision Mychaela Falconia <falcon@freecalypso.org> parents: 473 diff changeset	230 malloc(). To make such alternative schemes possible, the following const
bd32bb1e8dab doc/EFR-library-API: document malloc-alternative provision Mychaela Falconia <falcon@freecalypso.org> parents: 473 diff changeset	231 "variables" are provided beginning with libgsmefr version 1.2.0:
bd32bb1e8dab doc/EFR-library-API: document malloc-alternative provision Mychaela Falconia <falcon@freecalypso.org> parents: 473 diff changeset	232
bd32bb1e8dab doc/EFR-library-API: document malloc-alternative provision Mychaela Falconia <falcon@freecalypso.org> parents: 473 diff changeset	233 extern const unsigned EFR_encoder_state_size;
bd32bb1e8dab doc/EFR-library-API: document malloc-alternative provision Mychaela Falconia <falcon@freecalypso.org> parents: 473 diff changeset	234 extern const unsigned EFR_decoder_state_size;
bd32bb1e8dab doc/EFR-library-API: document malloc-alternative provision Mychaela Falconia <falcon@freecalypso.org> parents: 473 diff changeset	235
bd32bb1e8dab doc/EFR-library-API: document malloc-alternative provision Mychaela Falconia <falcon@freecalypso.org> parents: 473 diff changeset	236 Using this feature, one can replace EFR_encoder_create() and
bd32bb1e8dab doc/EFR-library-API: document malloc-alternative provision Mychaela Falconia <falcon@freecalypso.org> parents: 473 diff changeset	237 EFR_decoder_create() with something like the following (example for
bd32bb1e8dab doc/EFR-library-API: document malloc-alternative provision Mychaela Falconia <falcon@freecalypso.org> parents: 473 diff changeset	238 applications based on Osmocom libraries):
bd32bb1e8dab doc/EFR-library-API: document malloc-alternative provision Mychaela Falconia <falcon@freecalypso.org> parents: 473 diff changeset	239
bd32bb1e8dab doc/EFR-library-API: document malloc-alternative provision Mychaela Falconia <falcon@freecalypso.org> parents: 473 diff changeset	240 struct EFR_encoder_state *enc_state;
bd32bb1e8dab doc/EFR-library-API: document malloc-alternative provision Mychaela Falconia <falcon@freecalypso.org> parents: 473 diff changeset	241 enc_state = talloc_size(ctx, EFR_encoder_state_size);
bd32bb1e8dab doc/EFR-library-API: document malloc-alternative provision Mychaela Falconia <falcon@freecalypso.org> parents: 473 diff changeset	242 if (enc_state)
bd32bb1e8dab doc/EFR-library-API: document malloc-alternative provision Mychaela Falconia <falcon@freecalypso.org> parents: 473 diff changeset	243 EFR_encoder_reset(enc_state, dtx_flag);
bd32bb1e8dab doc/EFR-library-API: document malloc-alternative provision Mychaela Falconia <falcon@freecalypso.org> parents: 473 diff changeset	244
bd32bb1e8dab doc/EFR-library-API: document malloc-alternative provision Mychaela Falconia <falcon@freecalypso.org> parents: 473 diff changeset	245 struct EFR_decoder_state *dec_state;
bd32bb1e8dab doc/EFR-library-API: document malloc-alternative provision Mychaela Falconia <falcon@freecalypso.org> parents: 473 diff changeset	246 dec_state = talloc_size(ctx, EFR_decoder_state_size);
bd32bb1e8dab doc/EFR-library-API: document malloc-alternative provision Mychaela Falconia <falcon@freecalypso.org> parents: 473 diff changeset	247 if (dec_state)
bd32bb1e8dab doc/EFR-library-API: document malloc-alternative provision Mychaela Falconia <falcon@freecalypso.org> parents: 473 diff changeset	248 EFR_decoder_reset(dec_state);
bd32bb1e8dab doc/EFR-library-API: document malloc-alternative provision Mychaela Falconia <falcon@freecalypso.org> parents: 473 diff changeset	249
473 2d46abdfbe91 libgsmefr version 1.1.0 for DHF addition Mychaela Falconia <falcon@freecalypso.org> parents: 463 diff changeset	250 Public const datum: decoder homing frame
2d46abdfbe91 libgsmefr version 1.1.0 for DHF addition Mychaela Falconia <falcon@freecalypso.org> parents: 463 diff changeset	251 ========================================
2d46abdfbe91 libgsmefr version 1.1.0 for DHF addition Mychaela Falconia <falcon@freecalypso.org> parents: 463 diff changeset	252
2d46abdfbe91 libgsmefr version 1.1.0 for DHF addition Mychaela Falconia <falcon@freecalypso.org> parents: 463 diff changeset	253 While the encoder homing frame is the same for all codecs defined by ETSI and
2d46abdfbe91 libgsmefr version 1.1.0 for DHF addition Mychaela Falconia <falcon@freecalypso.org> parents: 463 diff changeset	254 then later 3GPP, each codec has its own unique decoder homing frame (DHF). A
2d46abdfbe91 libgsmefr version 1.1.0 for DHF addition Mychaela Falconia <falcon@freecalypso.org> parents: 463 diff changeset	255 public const datum introduced in libgsmefr version 1.1.0 provides the
2d46abdfbe91 libgsmefr version 1.1.0 for DHF addition Mychaela Falconia <falcon@freecalypso.org> parents: 463 diff changeset	256 RTP-encoded form of the ETSI-prescribed DHF for EFR:
2d46abdfbe91 libgsmefr version 1.1.0 for DHF addition Mychaela Falconia <falcon@freecalypso.org> parents: 463 diff changeset	257
2d46abdfbe91 libgsmefr version 1.1.0 for DHF addition Mychaela Falconia <falcon@freecalypso.org> parents: 463 diff changeset	258 extern const uint8_t EFR_decoder_homing_frame[EFR_RTP_FRAME_LEN];

FreeCalypso > hg > gsm-codec-lib

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