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Vector excitation coding with dynamic bit allocationVector excitation coding (VXC) has shown promise for digital transmission of fairly high communications quality speech at low bit rates, but current version of the algorithm still suffer from audible degradations, particularly at 4.8 kb/s. The authors examine the technique of dynamic bit allocation (DBA) to improve the performance of VXC for a given bit rate. The approach is based on the observation that the minimum bit rate needed to code adequately both the long-term and short-term predictors in VXC varies dynamically with time. Therefore, in frames where fewer bits suffice for the predictors, the unneeded bits can be reallocated to other coder parameter sets such as excitation vectors. By dynamically distributing available bits among the different coder parameter sets while keeping the total number of bits in each frame fixed, it is possible to improve overall coder performance without increasing bit rate.
Document ID
19890039396
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Yong, Mei
(California Univ. Santa Barbara, CA, United States)
Gersho, Allen
(California, University Santa Barbara, United States)
Date Acquired
August 14, 2013
Publication Date
January 1, 1988
Subject Category
Communications And Radar
Meeting Information
Meeting: GLOBECOM ''88 - IEEE Global Telecommunications Conference and Exhibition
Location: Hollywood, FL
Country: United States
Start Date: November 28, 1988
End Date: December 1, 1988
Accession Number
89A26767
Distribution Limits
Public
Copyright
Other

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