Cross-domain processing for noise and echo suppression

摘要

An audio-based system may perform noise and echo suppression by initially processing an audio signal that is subject to acoustic echo or echo resulting from other system characteristics. The audio signal is processed in the time domain using an adaptive echo-cancellation filter. The audio is then further processed in the frequency domain to simultaneously reduce background noise and residual echo.

主权项

1. A computing device, comprising:
a processor; a microphone; a speaker configured to render audio based at least in part on an output audio signal; and memory, accessible by the processor and storing instructions that are executable by the processor to perform acts comprising:
receiving an input audio signal from the microphone, wherein the input audio signal includes an echo component resulting from the rendered audio;estimating an echo signal corresponding to the echo component of the input audio signal based at least in part on the output audio signal;subtracting the estimated echo signal from the input audio signal to produce an echo-suppressed audio signal;calculating a frequency-domain representation of the echo-suppressed audio signal;calculating a frequency-domain representation of the estimated echo signal;estimating noise values corresponding to different frequencies of the echo-suppressed audio signal based at least in part on the calculated frequency-domain representation of the echo-suppressed audio signal;calculating gain values corresponding respectively to the different frequencies based at least in part on (a) the estimated noise values of the echo-suppressed audio signal and (b) the calculated frequency-domain representation of the estimated echo signal;adjusting the frequency-domain representation of the echo-suppressed audio signal at the different frequencies in accordance with the calculated gain values corresponding to the different frequencies to produce an adjusted frequency-domain representation of the echo-suppressed audio signal; andproducing a processed audio signal based at least in part on the adjusted frequency-domain representation of the echo-suppressed audio signal.