COMPARATIVE STUDY OF WIDEBAND SPEECH SPECTRAL QUANTISATION SCHEMES
G. Guibi · 2008
In this treatise a range of Line Spectrum Frequency (LSF) Vector Quantization (VQ) schemes were studied comparatively, which were designed for wideband speech codecs. Both predictive arrangements and memoryless schemes were investigated. Specifically, both memoryless Split Vector Quantization (SVQ) and Classified Vector Quantization (CVQ) were studied. These techniques exhibit a low complexity and high channel error resilience, but require high bit rates for maintaining high speech quality. By contrast, Predictive Vector Quantizers (PVQ) offer a reduced Spectral Distortion (SD) performance, although they are sensitive to channel error propagation. It is shown that the family of the so-called Safety-Net Vector Quantizers (SNVQ) offers a good design compromise in this sense.