CELP coding based on mel-cepstral analysis
Kazuhito Koishida, Keiichi Tokuda, Takao Kobayashi, Satoshi Imai · 2002
We propose a CELP coder based on mel-cepstral analysis. In the coder, since the transfer functions of perceptual weighting and postfiltering are defined through mel-cepstral coefficients, the effects of perceptual weighting and postfiltering should fit with the characteristics of the human auditory sensation. We use a basic CELP structure without adaptive codebook, and the subjective speech quality of the proposed coder in terms of the opinion equivalent Q is measured and compared with that of the conventional CELP coder. It is shown that the improvement of more than 1.8 dB is achieved by the proposed coder over the conventional CELP coder.