VOICE ACTIVITY DETECTOR

摘要

A voice activity detector (100) includes an analyser (101) for analysing an input signal representing an audio signal to determine if speech is present in the audio signal and for producing an output state signal (01) accordingly, a state change delay (103) for receiving an output state signal(Ol) from the analyser, for detecting a change of value of the received output state signal and for maintaining a current state of the received output state signal until a pre-determined delay period has elapsed to produce an output state signal (02) and a signal quality estimator (105) for estimating a current quality value of the analysed input signal and for producing an output signal (O3) indicating the estimated value, wherein the state change delay (103) is operable to apply a delay period which has a variable value which is determined adaptively according to a current value of the output signal (03) of the signal quality estimator.