The invention relates to the field of voice technologies, in particular to a self-
adaptive denoising method based on sub-band
noise analysis. The method includes the steps that firstly, framing and short
time frequency domain transformation are conducted on input
time domain audio signals with
noise, and then
frequency domain audio signals with
noise are generated; secondly, a
noise energy spectrum of the
frequency domain audio signals with noise is estimated through a minimum value tracking method; thirdly, the posterior
signal to noise ratio and the prior
signal to noise ratio of the
noise energy spectrum are calculated; fourthly, through a
nonlinear gain extension method, denoising gains of all time frequency units are calculated through the posterior
signal to noise ratio and the prior
signal to noise ratio; fifthly,
smoothing filtering is conducted on the denoising gains of all the time frequency units to reduce tone quality
distortion; sixthly, the denoising gains act on all the time frequency units of the audio signals with noise in the first step, and then denoised
frequency domain audio signals are acquired; seventhly, short
time frequency domain inverse transformation is conducted, and then the final denoised time frequency audio signals are acquired and output. According to the method and
system, stable noise in target signals can be greatly lowered.