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Work item:
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G.729.1 (2006) Amd.5
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Subject/title:
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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
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Status:
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[Carried to next study period]
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Approval process:
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AAP
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Type of work item:
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Recommendation
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Version:
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-
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Equivalent number:
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-
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Timing:
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-
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Liaison:
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ITU-T Q7/12
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Supporting members:
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-
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Summary:
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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.
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Comment:
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-
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Reference(s):
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Historic references:
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Contact(s):
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| ITU-T A.5 justification(s): |
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First registration in the WP:
2008-10-01 16:17:53
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Last update:
2008-10-07 10:15:33
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