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function ccc = mfcc(x) 
 
%归一化mel滤波器组系数 
bank = melbankm(24,256,8000,0,0.5,'m'); 
bank = full(bank); 
bank = bank/max(bank(:)); 
 
%DCT系数，12×24 
for k=1:12 
    n = 0:23; 
    dctcoef(k,:) = cos((2*n+1)*k*pi/(2*24)); 
end 
 
%归一化倒谱提升窗口 
w = 1+6*sin(pi*[1:12]./12); 
w = w/max(w); 
 
%预加重滤波器 
xx = double(x); 
xx = filter([1 -0.9375],1,xx); 
 
%语言信号分帧 
xx = enframe(xx,256,80); 
 
%计算每帧的MFCC参数 
for i = 1:size(xx,1) 
    y = xx(i,:); 
    s = y' .*hamming(256); 
    t = abs(fft(s)); 
    t = t.^2; 
    c1 = dctcoef * log(bank *t(1:129)); 
    c2 = c1.*w'; 
    m(i,:) = c2'; 
end 
 
%差分参数 
dtm = zeros(size(m)); 
for i=3:size(m,1)-2 
    dtm(i,:) = -2*m(i-2,:)-m(i-1,:)+m(i+1,:)+2*m(i+2,:); 
end 
dtm = dtm/3; 
 
%合并mfcc参数和一阶差分mfcc参数 
ccc = [m dtm]; 
%去除首尾两帧，因为这两帧的一阶差分参数为0 
ccc = ccc(3:size(m,1)-2,:);