function ccc = mfcc(x)
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% function ccc=mfcc(x);
%对输入的语音序列x进行MFCC参数的提取，返回MFCC参数和一阶
%差分MFCC参数，Mel滤波器的阶数为24
%fft变换的长度为256，采样频率为8000Hz，对x 256点分为一帧
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
bank=melbankm(24,256,48000,0,0.5,'m');
% 归一化mel滤波器组系数
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);
% 语音信号分帧
xx=enframe(xx,256,80); %xx是一个多维数组
% 计算每帧的MFCC参数
for i=1:size(xx,1)%size(xx,1)返回xx的维数(行数)
y = xx(i,:);
s = y' .* hamming(256);%乘窗
t = abs(fft(s));
t = t.^2;%计算能量
c1=dctcoef * log(bank * t(1:129));% dctcoef为DCT系数，bank归一化mel滤波器组系数
c2 = c1.*w'; % w为归一化倒谱提升窗口
m(i,:)=c2';
end
%差分系数
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]; %ccc是矩阵
%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,:);
fid = fopen('d.txt','wt'); % 打开文件
%for i = 0 : size(ccc)
fprintf(fid,'%f',ccc);
%end
fclose(fid); %关闭文件
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