Predictive multiple-scale lattice VQ for LSF quantization
Adriana Vasilache, Marcel Vasilache, I. Tabus · 1999
This paper introduces a new lattice quantization scheme, the multiple-scale lattice vector quantization (MSLVQ), based on the truncation of the D/sub 10//sup +/ lattice. The codebook is composed of several copies of the truncated lattice scaled with different scaling factors. A fast nearest neighbor search is introduced. We compare the performance of predictive MSLVQ for quantization of line spectrum frequency (LSF) coefficients with the quantization technique used in the G.729 codec and show the better performance of our method in terms of spectral distortion. The MSLVQ scheme achieves the transparent quality at 21 bits/frame.