Introduction - Digital Speech: Coding for Low Bit Rate Communication Systems - page 3

It is very important that the quantization of the linear prediction coefficients
(LPC) of low bit-rate speech coders is performed efficiently both in terms of
bit rate and sensitivity to channel errors. Hence, in Chapter 5, efficient quan-
tization schemes of LPC parameters in the form of Line Spectral Frequencies
are formulated, tested and compared.
In Chapter 6, more detailed modelling/classification of speech is studied.
Various pitch estimation and voiced - unvoiced classification techniques are
discussed.
In Chapter 7, after a general discussion of analysis by synthesis LPC coding
schemes, code-excited linear prediction (CELP) is discussed in detail.
In Chapter 8, a brief review harmonic coding techniques is given.
In Chapter 9, a novel hybrid coding method, the integration of CELP and
harmonic coding to form a multi-modal coder, is described.
Chapters 10 and 11 cover the topics of voice activity detection and speech
enhancements methods, respectively.