Design and description of CS-ACELP: a toll quality 8 kb/s speech coder
Redwan A. Salami, Claude B. Laflamme, J.-P. Adoul, A. Kataoka, S. Hayashi, Takehiro Moriya, Claude Lamblin, Dominique Massaloux, Stéphane Proust, P. Kroon, Yair Shoham · IEEE Transactions on Speech and Audio Processing · 1998
This paper describes the 8 kb/s speech coding algorithm G.729 which has been standardized by ITU-T. The algorithm is based on a conjugate-structure algebraic CELP (CS-ACELP) coding technique and uses 10 ms speech frames. The codec delivers toll-quality speech (equivalent to 32 kb/s ADPCM) for most operating conditions. This paper describes the coder structure in detail and discusses the reasons behind certain design choices. A 16-b fixed-point version has been developed as part of Recommendation G.729 and a summary of the subjective test results based on a real-time implementation of this version are presented.