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Published on: February 21, 2011
An intrusive method for estimating speech intelligibility from noisy and distorted signals
Nursadul Mamun1, Muhammad S A Zilany2, John H L Hansen1
1Department of Electrical and Computer Engineering, University of Texas at Dallas, Richardson, Texas 75080, USA.
A new objective metric, the spectrogram orthogonal polynomial measure (SOPM), accurately predicts speech intelligibility in normal-hearing individuals under various noise and distortion conditions. This metric shows high correlation with subjective scores, offering a reliable tool for voice communication research.
Area of Science:
- Speech processing
- Acoustics
- Signal processing
Background:
- Objective speech intelligibility metrics are crucial for voice communication systems.
- Existing metrics often focus on single noise or distortion types.
- A comprehensive metric for diverse adverse conditions is needed.
Purpose of the Study:
- To propose and evaluate a novel objective metric, the spectrogram orthogonal polynomial measure (SOPM).
- To predict speech intelligibility for normal-hearing listeners under various adverse conditions.
- To assess the metric's performance across different noise and distortion types.
Main Methods:
- Developed the SOPM metric using Krawtchouk moments for feature extraction from spectrograms.
- Evaluated the metric against subjective intelligibility scores from normal-hearing subjects.
- Tested performance under steady-state and fluctuating noise, clipping, phase jitters, time-frequency segregation, and reverberation.
Main Results:
- The SOPM metric demonstrated high correlation (0.97-0.996) with subjective intelligibility scores.
- The metric performed well across a wide range of noise and distortion conditions.
- Achieved robust predictions for speech intelligibility in both quiet and noisy environments.
Conclusions:
- The proposed spectrogram orthogonal polynomial measure (SOPM) is a promising objective metric for predicting speech intelligibility.
- SOPM offers a reliable and accurate method for assessing speech quality under diverse adverse conditions.
- This metric can advance the development of robust voice communication technologies.
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