Scalar and Lattice Hybrid Quantization of LSF

To reduce the computational complexity and storage of the line spectrum frequency(LSF) parameters quantizer,a scalar and lattice hybrid quantizer is designed to quantize LSF parameters based on the attractive properties of lattice vector quantization(LVQ).The first and second components of the LSF predictive error vector are quantized by scalar quantization,but the rest components are quantized by LVQ,which takes advantage of lattice's properties to effectively reduce the complexity of the design and search of the codebook and also decrease the storage.Experimental results show that this quantizer has comparable performance with the LSF quantization method used by G.729.