An 8-kb/s conjugate-structure algebraic CELP (CS-ACELP) speech coding

The ITU-T issued the new recommendation G.729 in 1996, to realize a high-quality and low-delay speech coder at 8-kb/s. In this paper, the algorithm for conjugate-structure algebraic code-excited linear prediction (CS-ACELP) is discussed, and its central aspects are analyzed in detail. Topics covered include the special codebook structure, efficient codebook search strategies and speech improvement approaches.