ITU-T Work Programme

[2005-2008] : [SG16] : [Q10/16]

[Declared patent(s)] - [Publication]

Work item:

G.729.1 (2006) Amd.4 (ex G.729.1-DTX-CNG)

Subject/title:

G.729-based embedded variable bit-rate coder: An 8-32 kbit/s scalable wideband coder bitstream interoperable with G.729: New Annex C (DTX/CNG scheme) plus corrections to main body and Annex B

Status:

Approved on 2008-06-29

Approval process:

AAP

Type of work item:

Recommendation

Version:

Equivalent number:

Timing:

Liaison:

ITU-T Q7/12

Supporting members:

Summary:

This document contains corrections to ITU-T G.729.1 for Consent under AAP. In addition to corrections to C-source codes agreed at the last WP3/16 meeting (COM16-R24), it also contains the revised set of test vectors and a revision of Table 5/G.729.1 (complexity figures) with the data evaluated during G.729.1 DTX/CNG characterization phase and given in the new annex C to G.729.1 (G.729.1. DTX/CNG scheme). This document also describes a new annex C for silence and noise coding scheme for G.729.1, comprising DTX/CNG algorithms and a scalable SID structure which is interoperable with G.729 annex B for Consent under AAP. As G.729.1 coder, the silence compression scheme operates on 20 ms frames and has an algorithmic delay of 48.9375 ms. By default, the encoder input and decoder output are sampled at 16 kHz. The encoder produces an embedded bitstream structured in 3 layers, core lower band (50-4000 Hz) layer, enhancement lower band layer and a higher band (4000-7000 Hz) layer. As G.729.1 bitstream, the bitstream can be truncated at the decoder side or by any component of the communication system to adjust "on the fly" the bit rate to the desired value with no need for outband signaling. The corrections bring changes necessary to the existing C code (Release 1.2) of ITU-T Rec. G.729.1 Main Body and Annex B. The corrected C code will be labelled as Release 1.3.

Comment:

Reference(s):

[SG16-TD528-PLEN (2008-04)

]

[ToR & schedule: TD 297R1/WP3 Annex Q10.F]

Historic references:

[ToR & schedule: TD 297R1/WP3 Annex Q10.F]

Contact(s):

Stéphane Ragot, Editor

Eyal Shlomot, Editor

ITU-T A.5 justification(s):

[Submit new A.5 justification

]
See guidelines for creating & submitting ITU-T A.5 justifications

First registration in the WP: 2008-02-15 10:01:19

Last update: 2008-05-15 15:25:31

Committed to connecting the world

ITU-T work programme

[2005-2008] : [SG16] : [Q10/16]

[Declared patent(s)] - [Publication]