CONF
weber-ar-00-42-01/IDIAP
HMM2- Extraction of Formant Features and their Use for Robust ASR
Weber, Katrin
Bengio, Samy
Bourlard, Hervé
EXTERNAL
https://publications.idiap.ch/attachments/reports/2000/rr00-42.pdf
PUBLIC
https://publications.idiap.ch/index.php/publications/showcite/weber-rr-00-42
Related documents
European Conference on Speech Communication and Technology (Eurospeech 2001)
2001
Aalborg, Denmark
September 2001
607-610
IDIAP-rr 00-42
As recently introduced, an HMM2 can be considered as a particular case of an HMM mixture in which the HMM emission probabilities (usually estimated through Gaussian mixtures or an artificial neural network) are modeled by state-dependent, feature-based HMM (referred to as frequency HMM). A general EM training algorithm for such a structure has already been developed. Although there are numerous motivations for using such a structure, and many possible ways to exploit it, this paper will mainly focus on one particular instantiation of HMM2 in which the frequency HMM will be used to extract formant structure information, which will then be used as additional acoustic features in a standard Automatic Speech Recognition (ASR) system. While the fact that this architecture is able to automatically extract meaningful formant information is interesting by itself, empirical results will also show the robustness of these features to noise, and their potential to enhance regular HMM-based ASR.
REPORT
weber-rr-00-42/IDIAP
HMM2- Extraction of Formant Features and their Use for Robust ASR
Weber, Katrin
Bengio, Samy
Bourlard, Hervé
EXTERNAL
https://publications.idiap.ch/attachments/reports/2000/rr00-42.pdf
PUBLIC
Idiap-RR-42-2000
2000
IDIAP
Martigny, Switzerland
Published: Eurospeech 2001, Aalborg
As recently introduced, an HMM2 can be considered as a particular case of an HMM mixture in which the HMM emission probabilities (usually estimated through Gaussian mixtures or an artificial neural network) are modeled by state-dependent, feature-based HMM (referred to as frequency HMM). A general EM training algorithm for such a structure has already been developed. Although there are numerous motivations for using such a structure, and many possible ways to exploit it, this paper will mainly focus on one particular instantiation of HMM2 in which the frequency HMM will be used to extract formant structure information, which will then be used as additional acoustic features in a standard Automatic Speech Recognition (ASR) system. While the fact that this architecture is able to automatically extract meaningful formant information is interesting by itself, empirical results will also show the robustness of these features to noise, and their potential to enhance state-of-the-art noise-robust HMM-based ASR.