Method and device for reducing voice reverberation based on double microphones

Abstract

The invention discloses a method and a device for reducing voice reverberation based on double microphones. The method comprises the steps of calculating a transfer function h(t) from a secondary microphone to a primary microphone according to an input signal x(t) of the primary microphone and an input signal x(t) of the secondary microphone; judging the strength of reverberation according to h(t) and calculating a regulatory factor β of a gain function by taking a tail section h(t) of the h(t); obtaining a late reverberation estimation signal {circumflex over (r)}(t) of x(t) with the convolution of x(t) and h(t); calculating the gain function according to the frequency spectrum of x(t), β and frequency spectrum of {circumflex over (r)}(t); obtaining the reverberation removed frequency spectrum of x(t) by multiplying the frequency spectrum of x(t) by the gain function; and obtaining a late reverberation removed time-domain signal of x(t) by frequency-time conversion. Thus, the late reverberation can be removed from the input signal of the primary microphone, early reverberation can be preserved, processed voice is not caused to be thin, and the voice quality is improved. Meanwhile, spectral subtraction intensity is adjusted according to the strength of the reverberation so as to ensure that the voice is not damaged on the condition that the reverberation is weak and the voice intelligibility is originally high. Accurate estimation of DOA of direct sound is not needed, and therefore the microphones are not required to have high consistency.