基于Matlab编写的语音端点检测程序
function = vad(x)%幅度归一化到[-1,1]
x = double(x);
x = x / max(abs(x));
%常数设置
FrameLen = 240;
FrameInc = 80;
amp1 = 10;
amp2 = 2;
zcr1 = 10;
zcr2 = 5;
maxsilence = 8;% 6*10ms= 30ms
minlen= 15; % 15*10ms = 150ms
status= 0;
count = 0;
silence = 0;
%计算过零率
tmp1= enframe(x(1:end-1), FrameLen, FrameInc);
tmp2= enframe(x(2:end), FrameLen, FrameInc);
signs = (tmp1.*tmp2)<0;
diffs = (tmp1 -tmp2)>0.02;
zcr = sum(signs.*diffs, 2);
%计算短时能量
amp = sum(abs(enframe(filter(, 1, x), FrameLen, FrameInc)), 2);
%调整能量门限
amp1 = min(amp1, max(amp)/4);
amp2 = min(amp2, max(amp)/8);
%开始端点检测
x1 = 0;
x2 = 0;
for n=1:length(zcr)
goto = 0;
switch status
case {0,1} % 0 = 静音, 1 = 可能开始
if amp(n) > amp1 % 确信进入语音段
x1 = max(n-count-1,1);
status= 2;
silence = 0;
count = count + 1;
elseif amp(n) > amp2 | ... % 可能处于语音段
zcr(n) > zcr2
status = 1;
count= count + 1;
else % 静音状态
status= 0;
count = 0;
end
case 2, % 2 = 语音段
if amp(n) > amp2 | ... % 保持在语音段
zcr(n) > zcr2
count = count + 1;
else % 语音将结束
silence = silence+1;
if silence < maxsilence % 静音还不够长,尚未结束
count= count + 1;
elseif count < minlen % 语音长度太短,认为是噪声
status= 0;
silence = 0;
count = 0;
else % 语音结束
status= 3;
end
end
case 3,
break;
end
end
count = count-silence/2;
x2 = x1 + count -1;
subplot(311)
plot(x)
axis()
ylabel('Speech');
line(, [-1 1], 'Color', 'red');
line(, [-1 1], 'Color', 'red');
subplot(312)
plot(amp);
axis()
ylabel('Energy');
line(, , 'Color', 'red');
line(, , 'Color', 'red');
subplot(313)
plot(zcr);
axis()
ylabel('ZCR');
line(, , 'Color', 'red');
line(, , 'Color', 'red'); 谢<BR>了<BR> 顶