Methods and apparatus for reducing audio conference noise using voice quality measures

摘要

Methods and apparatus for monitoring audio quality and controlling noise in telephone conferences. In one example, voice activity detection processing is implemented based on the energy in the audio signal of each channel and the zero crossing rate of the audio signal to differentiate noise from speech. Certain examples further include the use of a voice quality index and activity timer to determine audio quality.

主权项

1. A method of reducing noise in a multi-channel audio conference, the method comprising for each channel in the multi-channel audio conference:
receiving an audio signal; analyzing the audio signal using a voice activity detection process to determine whether the audio signal corresponds to voice or noise, the analyzing including calculating an energy of a packet of the audio signal, calculating a zero crossing rate (ZCR) of the packet, and comparing the energy of the packet against an energy threshold; determining that the audio signal is in an active state responsive to the energy of the packet exceeding the energy threshold, or that the audio signal is in an inactive state responsive to the energy of the packet not exceeding the energy threshold; recording an activity timer value equal to an amount of time elapsed until a change between the active state and the inactive state of the audio signal; calculating a voice quality index (VQI); and producing an indication that the audio signal contains voice based on a combination of the voice activity detection process, the activity timer value, and the VQI.