Hanky Panky, As far as I can understand, you're looking for a speech/silence decision algo.. Some that you could look at are - Short time zero crossing rate, STFT (look for high frequency noise in ambient noise).. Cepstral analysis (although absence of VT information doesnt always signify silence) .. Hope this helps.. Ruchir Astavans USC -- bulley shah chal uthay wassiyay jithay saray howan aannay na koi sadi zaat phochay na koi sanu manay...

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