G.729 : Coding of speech at 8 kbit/s using conjugate-structure algebraic-code-excited linear prediction
2007) iii
CONTENTS
Page
1 Scope 1
2 General description of the coder. 1
2.1 Encoder. 2
2.2 Decoder. 3
2.3 Delay. 4
2.4 Speech coder description 4
2.5 Notational conventions. 4
3 Functional description of the encoder. 7
3.1 Preprocessing 7
3.2 Linear prediction analysis and quantization . 7
3.3 Perceptual weighting 14
3.4 Open-loop pitch analysis 15
3.5 Computation of the impulse response 16
3.6 Computation of the target signal 16
3.7 Adaptive-codebook search . 17
3.8 Fixed codebook – Structure and search 19
3.9 Quantization of the gains 22
3.10 Memory update. 23
4 Functional description of the decoder. 24
4.1 Parameter decoding procedure . 24
4.2 Post-processing. 27
4.3 Encoder and decoder initialization . 29
4.4 Concealment of frame erasures 30
5 Bit-exact description of the CS-ACELP coder. 31
5.1 Use of the simulation software. 31
5.2 Organization of the simulation software 32
6 References. 35
Annex A – Reduced complexity 8 kbit/s CS-ACELP speech codec . 36
A.1 Introduction 36
A.2 General description of the codec 36
A.3 Functional description of the encoder 37
A.4 Functional description of the decoder 41
A.5 Bit-exact description of the reduced complexity CS-ACELP codec 43
Annex B – A silence compression scheme for G.729 optimized for terminals conforming
to ITU-T Recommendation V.70 44
B.1 Introduction 44
B.2 General description of the VAD/DTX/CNG algorithms 44
B.3 Detailed description of the VAD algorithm . 45
iv ITU-T Rec. G.729 (01/2007)
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B.4 Detailed description of the DTX/CNG algorithms. 52
B.5 Bit-exact description of the silence compression scheme 58
Annex C – Reference floating-point implementation for G.729 CS-ACELP 8 kbit/s
speech coding 60
C.1 Scope 60
C.2 Normative references 60
C.3 Overview 60
C.4 Algorithmic description 60
C.5 ANSI C code. 60
Annex C+ – Reference floating-point implementation for integrating G.729 CS-ACELP
speech coding main body with Annexes B, D and E 63
C+.1 Scope 63
C+.2 Normative references 63
C+.3 Overview 63
C+.4 New functionality . 63
C+.5 Algorithm description. 64
C+.6 Description of C source code . 68
Annex D – +CS-ACELP speech coding algorithm at 6.4 kbit/s 71
D.1 Scope 71
D.2 Normative references 71
D.3 General coder description for the 6.4 kbit/s extension . 71
D.4 Bit allocation 72
D.5 Functional description of the encoder 72
D.6 Functional description of decoder 73
D.7 ANSI C code. 73
Annex E – CS-ACELP speech coding algorithm at 11.8 kbit/s. 76
E.1 Introduction 76
E.2 General description of the speech codec 76
E.3 Functional description of the encoder 78
E.4 Functional description of the decoder 87
E.5 Bit-exact description of the CS-ACELP coder. 94
E.6 Bibliography. 96
Annex F – Reference implementation of G.729 Annex B DTX functionality for Annex D . 97
F.1 Scope 97
F.2 Normative references 97
F.3 Overview 97
F.4 New functionality . 97
F.5 Algorithm description. 97
F.6 Description of C source code . 98
ITU-T Rec. G.729 (01/2007) v
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Annex G – Reference implementation of Annex B DTX functionality for Annex E 101
G.1 Scope 101
G.2 Normative references 101
G.3 Overview 101
G.4 New functionality . 101
G.5 Algorithm description. 102
G.6 Description of C source code . 106
Annex H – Reference implementation of switching procedure between Annexes D and E . 110
H.1 Scope 110
H.2 Normative references 110
H.3 Overview 110
H.4 Algorithm description. 110
H.5 Description of C source code . 111
Annex I – Reference fixed-point implementation for integrating G.729 CS-ACELP
speech coding main body with Annexes B, D and E 114
I.1 Scope 114
I.2 Normative references 114
I.3 Overview 114
I.4 New functionality . 114
I.5 Algorithm description. 115
I.6 Description of C source code . 119
Annex J – An embedded variable bit-rate extension to G.729: An
interoperable 8-32 kbit/s scalable wideband extension to G.729 . 123
Appendix I – External synchronous reset performance for G.729 codecs in systems using
external VAD/DTX/CNG. 124
I.1 Introduction 124
I.2 Experimental design . 124
I.3 Performance observations 125
I.4 Conclusion 125
Appendix II – G.729 Annex B enhancements in voice-over-IP applications – Option 1 126
II.1 Scope 126
II.2 Abbreviations and acronyms 126
II.3 Introduction 126
II.4 Identified problems of G.729B in VoIP applications. 126
II.5 Experimental design . 127
II.6 Electronic attachments 131
vi ITU-T Rec. G.729 (01/2007)
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Appendix III – Annex B enhancements in voice-over-IP applications – Option 2 . 132
III.1 Scope 132
III.2 Solutions for the reported issues with Annex B . 132
III.3 Examples for the solutions of reported issues with Annex B. 132
III.4 Electronic attachments 136
http://www.itu.int/rec/dologin_pub.asp?lang=e&id=T-REC-G.729-200701-I!!SOFT-ZST-E&type=items
Si necesita alguien alguna otra norma de la itu avisen se las busco pasen el nombre como h.323 g.711 etc