MATLAB.zip_语音识别matlab

%端点检测程序 function [x1,x2] = 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 -0.9375], 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([1 length(x) -1 1]) ylabel('Speech'); line([x1*FrameInc x1*FrameInc], [-1 1], 'Color', 'red'); line([x2*FrameInc x2*FrameInc], [-1 1], 'Color', 'red'); subplot(312) plot(amp); axis([1 length(amp) 0 max(amp)]) ylabel('Energy'); line([x1 x1], [min(amp),max(amp)], 'Color', 'red'); line([x2 x2], [min(amp),max(amp)], 'Color', 'red'); subplot(313) plot(zcr); axis([1 length(zcr) 0 max(zcr)]) ylabel('ZCR'); line([x1 x1], [min(zcr),max(zcr)], 'Color', 'red'); line([x2 x2], [min(zcr),max(zcr)], 'Color', 'red');