Split vector quantization (SVQ) of LSF parameter suffers from huge com
plexity and storage requirements. Increasing the number of subvectors
M results in a considerable decrease in both complexity and storage, b
ut at the expense of rapid degradation in performance as M increases.
To alleviate this problem, we propose classified SVQ (CSVQ), which use
s class-dependent splitting and bit allocation schemes combined with a
classified VQ structure. For practical applications, we designed two
CSVQ structures. Experimental results have shown that both of the CSVQ
schemes achieve nearly transparent quantization at 28 bits/frame whil
e requiring much less complexity than the conventional SVQ. (C) 1997 E
lsevier Science B.V.