Second International Conference on Spoken Language Processing (ICSLP'92)

Banff, Alberta, Canada
October 13-16, 1992

A Low Bit-Rate CELP Coder Based on Multi-Path Search Methods

Maurizio Copperi

SIP Headquarters, R&D Department, Torino, Italy

This paper deals with the design and performance evaluation of a CELP codec at 3.5 kbit/s based on multi-path search methods. The rationale of this approach stems from the fact that delayed-decision coding algorithms outperform conventional techniques, in which the parameters to be transmitted are optimized sequentially. Tree codes have been applied to both the spectral information, quantized via a multi-stage vector quantizer, and the excitation codevectors, along with relative optimal gains. Preliminary results of this study show that the proposed scheme is a viable approach for achieving good speech quality at bit-rates below 4 kbit/s.

Full Paper

Bibliographic reference.  Copperi, Maurizio (1992): "A low bit-rate CELP coder based on multi-path search methods", In ICSLP-1992, 25-28.