Proceedings ArticleDOI
8 kbits/s Speech coder with pitch adaptive vector quantizer
TLDR
Computer simulation results show that the PAVQ is better in terms of speech quality than the conventional VQ under the condition of equal computational complexity.Abstract:
This paper proposes an 8 kbits/s speech coder with Pitch Adaptive Vector Quantizer (PAVQ), which efficiently quantizes the speech waveform in the time domain. The codebook of the PAVQ is classified into sub-groups each of which has the same maximum absolute magnitude (pitch peak) position. Each input vector is encoded by referring to the sub-group codebook having the same pitch peak position as that of the input vector, instead of referring to the whole codebook. If the codebook size of the PAVQ is equal to that of the conventional full-search VQ, computational complexity of the PAVQ is reduced much less than that of the conventional VQ. Computer simulation results show that the PAVQ is better in terms of speech quality than the conventional VQ under the condition of equal computational complexity. The PAVQ can be implemented in a single DSP and applicable memory IC chips.read more
Citations
More filters
PatentDOI
Depth-first algebraic-codebook search for fast coding of speech
TL;DR: In this article, a tree structure with levels ordered from 1 through M is used to reduce the search complexity of a codebook, which consists of a set of codevectors each of 40 positions and comprising N non-zero-amplitude pulses assignable to predetermined valid positions.
Patent
Algebraic codebook with signal-selected pulse amplitude/position combinations for fast coding of speech
TL;DR: In this paper, a codebook consisting of a set of pulse amplitude/position combinations is pre-selected in relation to the sound signal, and only this subset of combinations is searched, where each non-zero-amplitude pulse assumes at least one of q possible amplitudes.
Patent
Method of synthesizing a block of a speech signal in a CELP-type coder
TL;DR: In this paper, a hybrid stochastic codebook search technique including use of regular pulse excitation codebooks is described for a CELP-type speech codec based on a hybrid codebook.
Patent
Voice coder system.
TL;DR: In this paper, a voice coder system capable of coding at low bit rates under 4.8 kb/s with high speech quality is presented, where speech signals are divided into frames and further divided into subframes.
Patent
Fast sparse-algebraic-codebook search for efficient speech coding
TL;DR: In this article, the search complexity in finding the best codeword is greatly reduced by bringing the search back to the algebraic code domain, thereby allowing the sparsity of algebraic codes to speed up the necessary computations.
References
More filters
Journal ArticleDOI
An Algorithm for Vector Quantizer Design
Y. Linde,A. Buzo,Robert M. Gray +2 more
TL;DR: An efficient and intuitive algorithm is presented for the design of vector quantizers based either on a known probabilistic model or on a long training sequence of data.
Journal ArticleDOI
Speech coding based upon vector quantization
TL;DR: The vector quantizing approach is shown to be a mathematically and computationally tractable method which builds upon knowledge obtained in linear prediction analysis studies and is introduced in a nonrigorous form.
Proceedings ArticleDOI
Multiple stage vector quantization for speech coding
Biing-Hwang Juang,A. Gray +1 more
TL;DR: Experimental results show that the quantizer performance is very close to a theoretically predicted asymptotically optimal rate distortion relationship for Euclidean distance measures.
Journal ArticleDOI
Vector quantization of speech and speech-like waveforms
TL;DR: A comparison of the results for the real speech and the simulated speech provides a quantitative measure of the accuracy of such models and, hence, of the applicability of information theory bounds and code designs based on probabilistic models.
Proceedings ArticleDOI
A hardware implementation of a new narrow to medium band speech coding
TL;DR: A digital speech signal processor designed for a narrow band and a medium band speech coding system, both of them recently developed at the E.C.L., N.T.T., is described.