vad.m

提供了集中语音去噪的matlab代码

function [NoiseFlag, SpeechFlag, NoiseCounter, Dist]=vad(signal,noise,NoiseCounter,NoiseMargin,Hangover)

%[NOISEFLAG, SPEECHFLAG, NOISECOUNTER, DIST]=vad(SIGNAL,NOISE,NOISECOUNTER,NOISEMARGIN,HANGOVER)
%Spectral Distance Voice Activity Detector
%SIGNAL is the the current frames magnitude spectrum which is to labeld as
%noise or speech, NOISE is noise magnitude spectrum template (estimation),
%NOISECOUNTER is the number of imediate previous noise frames, NOISEMARGIN
%(default 3)is the spectral distance threshold. HANGOVER ( default 8 )is
%the number of noise segments after which the SPEECHFLAG is reset (goes to
%zero). NOISEFLAG is set to one if the the segment is labeld as noise
%NOISECOUNTER returns the number of previous noise segments, this value is
%reset (to zero) whenever a speech segment is detected. DIST is the
%spectral distance. 
%Saeed Vaseghi
%edited by Esfandiar Zavarehei
%Sep-04

if nargin<4
    NoiseMargin=3;
end
if nargin<5
    Hangover=8;
end
if nargin<3
    NoiseCounter=0;
end
    
FreqResol=length(signal);

SpectralDist= 20*(log10(signal)-log10(noise));
SpectralDist(find(SpectralDist<0))=0;

Dist=mean(SpectralDist); 
if (Dist < NoiseMargin) 
    NoiseFlag=1; 
    NoiseCounter=NoiseCounter+1;
else
    NoiseFlag=0;
    NoiseCounter=0;
end

% Detect noise only periods and attenuate the signal     
if (NoiseCounter > Hangover) 
    SpeechFlag=0;    
else 
    SpeechFlag=1; 
end