EUROSPEECH 2001 Scandinavia
7th European Conference on Speech Communication and Technology
2nd INTERSPEECH Event

Aalborg, Denmark
September 3-7, 2001

                 

A Computational Efficient Real Time Noise Robust Speech Recognition Based on Improved Spectral Subtraction Method

Bojan Kotnik, Zdravko Kacic, Bogomir Horvat

University of Maribor, Slovenia

In this paper, a speech enhancement method is presented, which uses spectral and time domain processing and achieves a trade-off between effective noise reduction and low computational load for real-time operations. First, a spectral subtraction method is used to reduce the effect of additive broadband noise on speech. Then, a novel weighting function is used to reduce a residual "musical noise" in time domain. This weighting function is a compound of a short-time zero crossing value and a short-time energy of speech signal. For evaluation of improvement of speech recognition the Slovenian SpeechDat FDB, the German SpeechDat FDB and SpeechDat-Car, as well as the Spanish SpeechDat FDB databases together with the HTK recognition toolkit were used. Word recognition accuracy in connected digits recognition task was improved by 8.7% for Slovenian FDB, by 5.1% for Spanish FDB, by 3.2% for German SpeechDat-Car, and by 2% for German SpeechDat FDB database.

Full Paper

Bibliographic reference.  Kotnik, Bojan / Kacic, Zdravko / Horvat, Bogomir (2001): "A computational efficient real time noise robust speech recognition based on improved spectral subtraction method", In EUROSPEECH-2001, 1123-1126.