The Nitech-NAIST HMM-Based Speech Synthesis System for the Blizzard Challenge 2006

We describe a statistical parametric speech synthesis system developed by a joint group from the Nagoya Institute of Technology (Nitech) and the Nara Institute of Science and Technology (NAIST) for the annual open evaluation of text-to-speech synthesis systems named Blizzard Challenge 2006. To improve our 2005 system (Nitech-HTS 2005), we investigated new features such as mel-generalized cepstrum-based line spectral pairs (MGC-LSPs), maximum likelihood linear transform (MLLT), and a full covariance global variance (GV) probability density function (pdf). A combination of mel-cepstral coefficients, MLLT, and full covariance GV pdf scored highest in subjective listening tests, and the 2006 system performed significantly better than the 2005 system. The Blizzard Challenge 2006 evaluations show that Nitech-NAIST-HTS 2006 is competitive even when working with relatively large speech databases.

[1]  Peder A. Olsen,et al.  Modeling inverse covariance matrices by basis expansion , 2004, IEEE Trans. Speech Audio Process..

[2]  Keiichi Tokuda,et al.  Eigenvoices for HMM-based speech synthesis , 2002, INTERSPEECH.

[3]  Hideki Kawahara,et al.  Restructuring speech representations using a pitch-adaptive time-frequency smoothing and an instantaneous-frequency-based F0 extraction: Possible role of a repetitive structure in sounds , 1999, Speech Commun..

[4]  Heiga Zen,et al.  The HMM-based speech synthesis system (HTS) version 2.0 , 2007, SSW.

[5]  Christina L. Bennett.  Large scale evaluation of corpus-based synthesizers: results and lessons from the blizzard challenge 2005 , 2005, INTERSPEECH.

[6]  Keiichi Tokuda,et al.  Simultaneous modeling of spectrum, pitch and duration in HMM-based speech synthesis , 1999, EUROSPEECH.

[7]  Hisashi Kawai,et al.  Constructing a Phonetic-Rich Speech Corpus While Controlling Time-Dependent Voice Quality Variability for English Speech Synthesis , 2006, 2006 IEEE International Conference on Acoustics Speech and Signal Processing Proceedings.

[8]  Heiga Zen,et al.  Details of the Nitech HMM-Based Speech Synthesis System for the Blizzard Challenge 2005 , 2007, IEICE Trans. Inf. Syst..

[9]  Keiichi Tokuda,et al.  Adaptation of pitch and spectrum for HMM-based speech synthesis using MLLR , 2001, 2001 IEEE International Conference on Acoustics, Speech, and Signal Processing. Proceedings (Cat. No.01CH37221).

[10]  Keiichi Tokuda,et al.  Efficient encoding of mel-generalized cepstrum for CELP coders , 1997, 1997 IEEE International Conference on Acoustics, Speech, and Signal Processing.

[11]  Keiichi Tokuda,et al.  Voice characteristics conversion for HMM-based speech synthesis system , 1997, 1997 IEEE International Conference on Acoustics, Speech, and Signal Processing.

[12]  Keiichi Tokuda,et al.  Mel-generalized cepstral analysis - a unified approach to speech spectral estimation , 1994, ICSLP.

[13]  Junichi Yamagishi,et al.  Average-Voice-Based Speech Synthesis , 2006 .

[14]  Ramesh A. Gopinath,et al.  Maximum likelihood modeling with Gaussian distributions for classification , 1998, Proceedings of the 1998 IEEE International Conference on Acoustics, Speech and Signal Processing, ICASSP '98 (Cat. No.98CH36181).

[15]  Ren-Hua Wang,et al.  USTC System for Blizzard Challenge 2006 an Improved HMM-based Speech Synthesis Method , 2006 .

[16]  Martine Grice,et al.  The SUS test: A method for the assessment of text-to-speech synthesis intelligibility using Semantically Unpredictable Sentences , 1996, Speech Commun..

[17]  Mark J. F. Gales,et al.  Semi-tied covariance matrices for hidden Markov models , 1999, IEEE Trans. Speech Audio Process..

[18]  Keiichi Tokuda,et al.  A 16 kbit/s wideband CELP coder using MEL-generalized cepstral analysis and its subjective evaluation , 1998, ICSLP.

[19]  Heiga Zen,et al.  Hidden semi-Markov model based speech synthesis , 2004, INTERSPEECH.

[20]  Keiichi Tokuda,et al.  The blizzard challenge - 2005: evaluating corpus-based speech synthesis on common datasets , 2005, INTERSPEECH.

[21]  Scott Axelrod,et al.  Modeling with a subspace constraint on inverse covariance matrices , 2002, INTERSPEECH.

[22]  Eric Moulines,et al.  Pitch-synchronous waveform processing techniques for text-to-speech synthesis using diphones , 1989, Speech Commun..

[23]  Heiga Zen,et al.  Statistical Parametric Speech Synthesis , 2007, 2007 IEEE International Conference on Acoustics, Speech and Signal Processing - ICASSP '07.

[24]  Jorge Nocedal,et al.  On the limited memory BFGS method for large scale optimization , 1989, Math. Program..

[25]  Heiga Zen,et al.  A Hidden Semi-Markov Model-Based Speech Synthesis System , 2007, IEICE Trans. Inf. Syst..

[26]  Heiga Zen,et al.  An overview of nitech HMM-based speech synthesis system for blizzard challenge 2005 , 2005, INTERSPEECH.

[27]  Keiichi Tokuda,et al.  Spectral representation of speech using mel‐generalized cepstral coefficients , 1996 .

[28]  Alan W. Black,et al.  Perfect synthesis for all of the people all of the time , 2002, Proceedings of 2002 IEEE Workshop on Speech Synthesis, 2002..

[29]  Keiichi Tokuda,et al.  Generalized cepstral analysis of speech - unified approach to LPC and cepstral method , 1990, ICSLP.

[30]  Tomoki Toda,et al.  Maximum likelihood voice conversion based on GMM with STRAIGHT mixed excitation , 2006, INTERSPEECH.

[31]  Takao Kobayashi,et al.  Speech Synthesis with Various Emotional Expressions and Speaking Styles by Style Interpolation and Morphing , 2005, IEICE Trans. Inf. Syst..

[32]  Keiichi Tokuda,et al.  A Speech Parameter Generation Algorithm Considering Global Variance for HMM-Based Speech Synthesis , 2007, IEICE Trans. Inf. Syst..

[33]  Keiichi Tokuda,et al.  Speaker interpolation in HMM-based speech synthesis system , 1997, EUROSPEECH.

[34]  Satoshi Imai,et al.  Cepstral analysis synthesis on the mel frequency scale , 1983, ICASSP.

[35]  Heiga Zen,et al.  An introduction of trajectory model into HMM-based speech synthesis , 2004, SSW.

[36]  R. Gopinath.  CONSTRAINED MAXIMUM LIKELIHOOD MODELING WITH GAUSSIAN DISTRIBUTIONS , 2001 .

[37]  Xia Wang,et al.  A Novel HMM-Based TTS System using Both Continuous HMMS and Discrete HMMS , 2007, 2007 IEEE International Conference on Acoustics, Speech and Signal Processing - ICASSP '07.