Title
Variable Dimension Vector Quantization of Speech Spectra for Low Rate Vocoders
Abstract
Optimal vector quantization of variable-dimension vectors in principle is feasible by using a set of fixed dimension VQ codebooks. However, for typical applications, such a multi-codebook approach demands a grossly excessive and impractical storage and com- putational complexity. Efficient quantization of such variable-dimension spectral shape vectors is the most challenging and difficult encoding task required in an important fam- ily of low bit-rate vocoders. We introduce a simple and effective formulation of variable-dimension vector quantization (VDVQ) which quantizes variable-dimension vectors using a single universal codebook having fixed dimension yet covering the entire range of input vector dimensions under consideration. This VDVQ technique is applied to quantize variable-dimension spectral shape vectors leading to a high quality speech coder at the low bit-rate of 2.5 kb/s. The combination of a universal spectral codebook and structured VQ reduces storage and computational complexity, yet delivers a high quantization efficiency and enhanced perceptual quality of the coded speech.
Year
DOI
Venue
1994
10.1109/DCC.1994.305949
Data Compression Conference
Keywords
Field
DocType
speech intelligibility,computational complexity,information processing,vector quantization,application software,encoding,speech coding,speech processing,spectral shape,random variables
Speech coding,Pattern recognition,Linde–Buzo–Gray algorithm,Computer science,Vector quantization,Artificial intelligence,Quantization (signal processing),Linear predictive coding,Codebook,Computational complexity theory,Encoding (memory)
Conference
Citations 
PageRank 
References 
11
1.67
1
Authors
3
Name
Order
Citations
PageRank
A. Das1111.67
Ajit V. Rao219720.50
Allen Gersho32031624.48