Acoustic Echo Preprocessing for Speech Enhancement

摘要

A method for cancelling/reducing acoustic echoes in speech/audio signal enhancement processing comprises selecting a long-term filter based on an echo tail length detection or an echo reverberation time detection of an microphone input signal; a reference signal is pre-processed with the selected long-term filter; the pre-processed reference signal is used to excite an adaptive filter wherein the output of the adaptive filter forms a replica signal of acoustic echo and/or acoustic echo tail; the replica signal of acoustic echo and/or acoustic echo tail is subtracted from a microphone input signal to suppress the acoustic echo and/or acoustic echo tail in the microphone input signal. The echo tail length or the echo reverberation time is detected by analyzing and comparing the microphone input signal and a received signal which is sent to a speaker. A strong long-term filter is selected if the detected echo tail length or the detected echo reverberation time is long; a weak long-term filter is selected if the detected echo tail length or the detected echo reverberation time is not long.

主权项

1. A method for cancelling/reducing acoustic echoes in speech/audio signal enhancement processing, the method comprising:
pre-processing a reference signal with a fixed long-term filter; using the pre-processed reference signal to excite an adaptive filter wherein the output of the adaptive filter forms a replica signal of acoustic echo and/or acoustic echo tail; subtracting the replica signal of acoustic echo and/or acoustic echo tail from a microphone input signal to suppress the acoustic echo and/or acoustic echo tail in the microphone input signal.