A Discrete-cepstrum Based Spectrum-envelope Estimation Scheme and Its Example Application of Voice Transformation

Hung-Yan Gu ； Sung-Feng Tsai

《中文計算語言學期刊》 14卷4期 (2009/12) Pp. 363-382

https://doi.org/10.30019/IJCLCLP.200912.0002

並列摘要

Approximating a spectral envelope via regularized discrete cepstrum coefficients has been proposed by previous researchers. In this paper, we study two problems encountered in practice when adopting this approach to estimate the spectral envelope. The first is which spectral peaks should be selected, and the second is which frequency axis scaling function should be adopted. After some efforts of trying and experiments, we propose two feasible solution methods for these two problems. Then, we combine these solution methods with the methods for regularizing and computing discrete cepstrum coefficients to form a spectral-envelope estimation scheme. This scheme has been verified, by measuring spectral-envelope approximation error, as being much better than the original scheme. Furthermore, we have applied this scheme to building a system for voice timbre transformation. The performance of this system demonstrates the effectiveness of the proposed spectral-envelope estimation scheme.

並列關鍵字

Spectral Envelope ； Discrete Cepstrum ； Harmonic-plus-noise Model ； Voice Timbre Transformation

參考文獻

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