Sir, I tried a matlab code for feature extraction using melfrequency cepstral coefficient (mfcc) but it showing error like "Matrix dimensions must agree.". How to correct the error?

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Suchithra K S
Suchithra K S on 2 Apr 2019
The code is given below,
clear all;
close all;
[x,fs1]=audioread('cryrumble.wav');
% ts1=1/fs1;
% N1=length(x);
% Tmax1=(N1-1)*ts1;
% fsu=fs/(N-1);
% t=(0:ts:Tmax);
% f=(-fs/2:fsu:fs/2);
% figure, subplot(411),plot(t,x),xlabel('Time'),title('Original Speech');
% subplot(412),plot(f,fftshift(abs(fft(x)))),xlabel('Freq (Hz)'),title('Frequency Spectrum');
% fs2 = (20/441)*fs1;
% na=resample(audio,2000,44100);
% N2=length(na);
ts1=1/fs1;
N1=length(x);
Tmax1=(N1-1)*ts1;
t1=(0:ts1:Tmax1);
figure;
plot(t1,x),xlabel('Time'),title('Original audio');
fs2 = (20/441)*fs1;
na=resample(x,2000,44100);
%sound(y,fs2);
ts2=1/fs2;
N2=length(na);
Tmax2=(N2-1)*ts2;
t2=(0:ts2:Tmax2);
fsu=fs2/(N2-1);
f=(-fs2/2:fsu:fs2/2);
% Step 1: Pre-Emphasis
a=[1];
b=[1 -0.95];
y=filter(b,a,na);
subplot(413),plot(t2,y),xlabel('Time'),title('Signal After High Pass Filter - Time Domain');
subplot(414),plot(f,fftshift(abs(fft(y)))),xlabel('Freq (Hz)'),title('Signal After High Pass Filter - Frequency Spectrum');
% Step 2: Frame Blocking
frameSize=882;
frame_duration=0.025;
frame_len = frame_duration*fs2;
framestep=0.01;
framestep_len=framestep*fs2;
num_frames =floor(N2/frame_len);
frames=[];
for j=1:num_frames
frame=na((j-1)*framestep_len + 1: ((j-1)*framestep_len)+frame_len);
max_val=max(frame);
if (max_val>0.025)
frames=[frames;frame'];
end
end
% Step 3: Hamming Windowing
NumFrames=size(frames,1);
hamm=hamming(frame_len)';
windowed=[];
for i=1:NumFrames
windowed(i,:)=frames(i,:).*hamm;
end
% Step 4: FFT
for i=1:NumFrames
ft(i,:)=abs(fft((windowed(i,:)),frame_len));
%plot(ft(i,:))
end
% Step 5: Mel Filterbanks
Lower_Frequency =100;
Upper_Frequency = fs2/2;
Nofilters=20;
lowhigh=[100 fs2/2];
%Here logarithm is of base 'e'
lh_mel=1125*(log(1+lowhigh/700));
mel=linspace(lh_mel(1),lh_mel(2),Nofilters+2);
figure;
plot(mel);
xlabel('frequency in Hertz');ylabel('mels');
title('melscale');
melinhz=700*(exp(mel/1125)-1);
%Converting to frequency resolution
fres=floor(((frameSize)+1)*melinhz/fs2);
%Creating the filters
for m =2:length(mel)-1
for k=1:frameSize/2
if k<fres(m-1)
H(m-1,k) = 0;
elseif (k>=fres(m-1)&&k<=fres(m))
H(m-1,k)= (k-fres(m-1))/(fres(m)-fres(m-1));
elseif (k>=fres(m)&&k<=fres(m+1))
H(m-1,k)= (fres(m+1)-k)/(fres(m+1)-fres(m));
elseif k>fres(m+1)
H(m-1,k) = 0;
end
end
end
%H contains the 20 filterbanks, we now apply it to the
%processed signal.
for i=1:NumFrames
for j=1:Nofilters
bankans(i,j)=sum((ft(i,:).*H(j,:)).^2);
end
end
figure;
plot(H);
xlabel('Frequency');ylabel('Magnitude');
title('Mel-Frequency Filter bank');
% Step 6: Nautral Log and DCT
% pkg load signal
%Here logarithm is of base '10'
logged=log10(bankans);
for i=1:NumFrames
mfcc(i,:)=dct2(logged(i,:));
end
%plotting the MFCC
figure
hold on
for i=1:NumFrames
plot(mfcc(i,1:13));
end
hold off
% save c5 mfcc
i= mfcc;
save i i
The error is like this,
Matrix dimensions must agree.
Error in mfccc (line 111)
bankans(i,j)=sum((ft(i,:).*H(j,:)).^2);

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