A 16 kb/s Wideband CELP-Based Speech Coder Using Mel-Generalized Cepstral Analysis
نویسندگان
چکیده
We propose a wideband CELP-type speech coder at 16 kb/s based on a mel-generalized cepstral (MGC) analysis technique. MGC analysis makes it possible to obtain a more accurate representation of spectral zeros compared to linear predictive (LP) analysis and take a perceptual frequency scale into account. A major advantage of the proposed coder is that the benefits of MGC representation of speech spectra can be incorporated into the CELP coding process. Subjective tests show that the proposed coder at 16 kb/s achieves a significant improvement in performance over a 16 kb/s conventional CELP coder under the same coding framework and bit allocation. Moreover, the proposed coder is found to outperform the ITU-T G.722 standard at 64 kb/s. key words: wideband speech coding, mel-generalized cepstral analysis, mel-generalized cepstrum, CELP coding
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