ISCA Archive Interspeech 2008
ISCA Archive Interspeech 2008

Spectral envelope recovery beyond the nyquist limit for high-quality manipulation of speech sounds

Hideki Kawahara, Masanori Morise, Hideki Banno, Toru Takahashi, Ryuichi Nisimura, Toshio Irino

A simple new method to recover details in a spectral envelope is proposed based on a recently introduced speech analysis, modification and resynthesis framework called TANDEM-STRAIGHT. Spectral envelope recovery of voiced sounds is a discrete-to-analog conversion in the frequency domain. However, there is a fundamental problem because the spatial frequency contents of vocal tract functions generally exceed the Nyquist limit of the equivalent sampling rate determined by the fundamental frequency. TANDEM-STRAIGHT yields a method to recover a spectral envelope based on the consistent sampling theory and provides base information for exceeding this limit. At the final stage, the AR spectral envelope estimated from the TANDEM-STRAIGHT spectrum is divided by the F0 adaptively smoothed version of itself to supply the missing high-spatial-frequency details of the envelope. The underlying principle of the proposed method can also be applied to other speech synthesis frameworks.


doi: 10.21437/Interspeech.2008-204

Cite as: Kawahara, H., Morise, M., Banno, H., Takahashi, T., Nisimura, R., Irino, T. (2008) Spectral envelope recovery beyond the nyquist limit for high-quality manipulation of speech sounds. Proc. Interspeech 2008, 650-653, doi: 10.21437/Interspeech.2008-204

@inproceedings{kawahara08_interspeech,
  author={Hideki Kawahara and Masanori Morise and Hideki Banno and Toru Takahashi and Ryuichi Nisimura and Toshio Irino},
  title={{Spectral envelope recovery beyond the nyquist limit for high-quality manipulation of speech sounds}},
  year=2008,
  booktitle={Proc. Interspeech 2008},
  pages={650--653},
  doi={10.21437/Interspeech.2008-204}
}