Noise estimation algorithm for non-stationary environments

摘要

Features are disclosed for estimating a noise level using a variable step size. An acoustic echo canceller (AEC) may be configured to perform echo cancellation. The acoustic echo canceller may determine an estimated echo using a playback signal. The acoustic echo canceller also may determine an estimated error using the estimated echo and a microphone signal. A variable step size may be determined using the estimated error and the microphone signal. Noise reduction may be performed using the variable step size.

主权项

1. A system comprising:
a speaker configured to produce sound using an audio playback signal; a microphone configured to detect the produced sound as a microphone signal; one or more processors in communication with the speaker and the microphone, the one or more processors configured to:
determine an estimated echo using the audio playback signal and a variable step size, the variable step size depending on whether near-end speech is present in the microphone signal;determine an estimated error using the estimated echo and the microphone signal;update the variable step size using the estimated error and the microphone signal;estimate a noise level of the microphone signal using the updated variable step size;perform noise reduction on the microphone signal using the estimate of the noise level, wherein the variable step size is determined using an average power of the audio playback signal, an average power of the microphone signal, and an average power of the estimated error, and wherein determining the variable step size comprises:
determining a numerator using the average power of the audio playback signal and the average power of the microphone signal;determining a denominator using the average power of the audio playback signal, the average power of the microphone signal, and the average power of the estimated error; anddividing the numerator by the denominator to determine the variable step size.