Scalar Quantization of Linear Prediction Coefficient
Wai C. Chu · 2003
In this chapter, the distance measure known as spectral distortion is defined, which is a widely used parameter to quantify the performance of a given LPC quantizer. Alternative representations of LPC, including reflection coefficient (RC), log area ratio (LAR) and line spectral frequency (LSF), are introduced. These representations are used in many coding standards for quantization purposes. Interpolation of the LPC is described at the end of the chapter. Note that only scalar quantizers are discussed here, and they are generally the technique of choice for coders standardized prior to 1994. For standards adopted after that year, some form of vector quantization is normally incorporated due to its superior performance.