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SNR-adaptive stream weighting for audio-MES ASR.
1Department of Electronic Engineering, Konkuk University, Seoul 143-701, Korea. kseung@konkuk.ac.kr
IEEE Transactions on Bio-Medical Engineering
|July 18, 2008
Summary
Myoelectric signals (MESs) from the mouth improve automatic speech recognition (ASR) in noisy environments. Integrating audio and MES features with adaptive weighting significantly boosts classification accuracy, outperforming audio-only ASR.
Area of Science:
- Speech processing
- Biomedical engineering
- Machine learning
Background:
- Automatic speech recognition (ASR) systems struggle with noise robustness.
- Myoelectric signals (MESs) from the mouth region offer a potential solution for noise-robust ASR.
Purpose of the Study:
- To integrate audio and facial MES features for improved ASR performance.
- To develop an adaptive weighting method for optimal feature fusion based on signal-to-noise ratio (SNR).
- To determine optimal SNR classification boundaries and stream weights using a maximum mutual information criterion.
Main Methods:
- Feature extraction from audio and facial MES data.
- Decision fusion of audio and MES features using a weighted linear combination of likelihoods.
- Development of an SNR-adaptive weighting process.
- Optimization of SNR classification boundaries and stream weights via maximum mutual information.
Main Results:
- MES-based ASR achieved 85.2% accuracy, significantly higher than audio-only ASR (25.5%).
- The proposed audio-MES weighting method further improved accuracy to 89.4% in babble noise.
- Consistent improvements were observed across various noise types (babble, car, aircraft, white noise).
Conclusions:
- Integrating audio and facial MES features enhances ASR noise robustness.
- SNR-adaptive weighting is effective for optimizing feature fusion in noisy conditions.
- The proposed method offers a promising approach for developing highly reliable ASR systems for real-world applications.
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