Patent ID: 7031916

Claim:
A method for improving estimates of average background noise energy in a G.729 Annex B compliant voice activity detection (VAD) device by substituting supplemental average background noise parameters derived according to a supplemental algorithm for a running average of background noise parameters derived according to G.729 Annex B, comprising: determining a maximum full-band energy, E max , and a minimum full-band energy, E min , from a plurality of incoming noise frames during a current period, i; generating a noise threshold, T noise, i+1 , for the next period, such that T noise, i+1 =min(2*min(T 1 , T 2 ), −21 dBm), where T 1 =E min +(E max −E min )/32, T 2 =4*E min , E max =the maximum block energy measured during the current updating period, and E min =the minimum block energy measured during the current updating period: determining a full-band energy of a current incoming noise frame, E i ; updating supplemental average background noise parameters to the current period: comparing the supplemental average background noise parameters of the current period to the running average of background noise parameters derived according to G.729 Annex B; and if the supplemental average background noise parameters of the current period diverge from the running average of the background noise parameters derived according to G.729 Annex B, then substituting the supplemental average background noise parameters of the current period for the running average of the background noise parameters derived according to G.729 Annex B.