Frequency domain techniques for speech coding
Ronald E. Crochiere, Jose M. Tribolet · The Journal of the Acoustical Society of America · 1979
Frequency domain techniques for speech coding have recently received considerable attention. The basic concept of these methods is to divide the speech into frequency components by a filter bank (subband coding) or by a suitable transform (transform coding) and then encode them using adaptive PCM. Four basic operations are involved in the design of these coders: (1) the type of transform or filter bank (analysis/synthesis), (2) the adaptive quantizer design (quantization theory), (3) the choice of bit allocation used by the quantizers (noise shaping and auditory masking), and (4) the control of the step-size of the quantizers (spectral estimation). This paper briefly reviews the basic aspects of the design of these four operations particularly as they apply to low bit-rate adaptive transform coding.