ISCA Archive Interspeech 2005
ISCA Archive Interspeech 2005

A novel voicing cut-off determination for low bit-rate harmonic speech coding

Changchun Bao, Jason Lukasiak, Christian Ritz

Generally, phonetic classification for low rate speech coding is restricted to either a simple binary voiced/unvoiced classification of entire speech frames, or alternatively, a more complicated estimation of the voicing for a set of frequency bands. A good compromise between these two techniques is estimation of a single cut-off frequency that separates the spectrum into voiced (below) and unvoiced (above) regions. Many existing cut-off frequency estimation methods use a fixed periodic spectrum to model voiced harmonics. However, due to pitch jitter, voiced harmonics do not always appear at regular intervals in the spectrum. In this paper a voicing cut-off estimation approach that combines speech energy, speech auto-correlation between frames and residual harmonic matching is proposed. Objective evaluation indicates that the algorithm is accurate and reliable. Subjective results obtained by embedding the algorithm in a low rate harmonic speech coder indicate that the technique is suitable for supporting high quality low rate speech synthesis. The proposed algorithm also requires relatively low complexity and introduces only a single frame of algorithmic delay.


doi: 10.21437/Interspeech.2005-808

Cite as: Bao, C., Lukasiak, J., Ritz, C. (2005) A novel voicing cut-off determination for low bit-rate harmonic speech coding. Proc. Interspeech 2005, 2709-2712, doi: 10.21437/Interspeech.2005-808

@inproceedings{bao05_interspeech,
  author={Changchun Bao and Jason Lukasiak and Christian Ritz},
  title={{A novel voicing cut-off determination for low bit-rate harmonic speech coding}},
  year=2005,
  booktitle={Proc. Interspeech 2005},
  pages={2709--2712},
  doi={10.21437/Interspeech.2005-808}
}