ITU-T Work Programme

[2009-2012] : [SG16] : [Q10/16]

[Declared patent(s)] - [Publication]

Work item:

G.729.1 (2006) Amd.5

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 D (Reference floating-point implementation for G.729.1 Annex C DTX/CNG) and corrections to the main body and Annex B

Status:

Approved on 2008-12-07 [Issued from previous study period]

Approval process:

AAP

Type of work item:

Recommendation

Version:

Equivalent number:

Timing:

Liaison:

ITU-T Q7/12

Supporting members:

Summary:

ITU-T Rec. G.729.1 contains the description of an algorithm for 8-32 kbit/s scalable coding interoperable with G.729. The specification in the main body uses fixed-point arithmetic, while its Annex B specifies an alternative implementation based on floating point arithmetic. Annex C added discontinuous transmission (DTX) and comfort noise generation (CNG) to G.729.1 and, similar to the main body of the Recommendation, uses fixed-point arithmetic. This silence removal feature provides significant reduction of bandwidth during inactive speech segments. New Annex D included in G.729.1 Amendment 5 provides an alternative implementation of the Annex C DTX/CNG mechanism using floating point arithmetic. Besides this new Annex, G.729.1 Amendment 5 incorporates changes needed to correct defects identified in the G.729.1 C source code for its main body and Annex B, and provides a revised set of test vectors. The corrections bring changes necessary to the existing C code (Release 1.3) of ITU-T Rec. G.729.1 Main Body and Annex B. The corrected C code will be labelled as Release 1.4.

Comment:

Reference(s):

[TD 387-WP3 (2008-10)

]

Historic references:

Contact(s):

Balazs KOVESI, Editor (G.729.1 main body and related annexes)

Stéphane RAGOT, Editor (Main body, Annex B)

Eyal SHLOMOT, Editor (Annex C, D)

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: 2008-10-01 16:17:53

Last update: 2010-06-28 17:02:25

Committed to connecting the world

ITU-T work programme

[2009-2012] : [SG16] : [Q10/16]

[Declared patent(s)] - [Publication]