How to get the name of each file in the folder

I want to extract the MFCC features of each .wav file. And I need to save the .mat file together with the name of .wav files.

e.g: hello.wav -> hello.mat

I tried using fileparts, but I found problems here:

Error using fileparts

Input must be a row vector of characters, or a string scalar, or a cellstr, or a string matrix.

Error in MFCC_extractor (line 5)

[filepath,name,ext] = fileparts(basedir);

addpath('C:\Users\DELL\Desktop\Reshape')
basedir = dir('C:\Users\DELL\Desktop\Reshape/*.wav'); % .wav directory 
 
for i = 1:numel(basedir) 
    [filepath,name,ext] = fileparts(basedir);
    [y,Fs] = audioread(fullfile(basedir(i).folder, basedir(i).name));% read audio 
    audio_data{i} = y(:,1); % make mono 
    [mfcc_data{i},delta,deltaDelta,loc] = mfcc(audio_data{i},Fs,NumCoeffs=20,LogEnergy="ignore");% extract mfccs 
    save(plus(name,'.mat'),mfcc_data);
end 
 

Answer 1

[Image Analyst]

Replace

[filepath,name,ext] = fileparts(basedir);
[y,Fs] = audioread(fullfile(basedir(i).folder, basedir(i).name));% read audio 

with

fullFileName = fullfile(basedir(i).folder, basedir(i).name);
[filepath,name,ext] = fileparts(fullFileName);
[y,Fs] = audioread(fullFileName);% read audio 

[Zhuoyi Ma]

HI, thanks! Now I am facing to a problem about saving the data to .mat file.

Would you please take a look at it?

----------ErrMsg--------

Arrays have incompatible sizes for this operation.

Error in MFCC_extractor (line 10)

save(plus(name,'.mat'),"mfcc_data",'-mat');

addpath('C:\Users\DELL\Desktop\Reshape')
basedir = dir('C:\Users\DELL\Desktop\Reshape/*.wav'); % .wav directory 
 
for i = 1:numel(basedir) 
    fullFileName = fullfile(basedir(i).folder, basedir(i).name);
    [filepath,name,ext] = fileparts(fullFileName);
    [y,Fs] = audioread(fullFileName);% read audio 
    audio_data{i} = y(:,1); % make mono 
    [mfcc_data{i},delta,deltaDelta,loc] = mfcc(audio_data{i},Fs,NumCoeffs=20,LogEnergy="ignore");% extract mfccs 
    save(plus(name,'.mat'),"mfcc_data",'-mat');
end 
 

[Image Analyst]

Replace:

save(plus(name,'.mat'),"mfcc_data",'-mat');

with

fillOutputFileName = fullfile(filepath, [name, '.mat']);
save(fillOutputFileName, "mfcc_data");

Answer 2

[jibrahim]

If you have access to Audio Toolbox, using an audioDatastore might simplify this. Here is an example (make sure the function myCustomWriter is on path):

% First, create a datastore that points to your audio files
ads = audioDatastore(basedir,IncludeSubfolders=true);

% Apply a transformation to the datastore. The transformed datastore
% extracts mfcc coefficients from the audio data
Fs =8000;
tds = transform(ads,@(x)mfcc(x,Fs,NumCoeffs=20,LogEnergy="ignore"));

% Write mfcc coefficients for each file to a MAT file
outputLocation = fullfile(tempdir,"myFeatures");
% If you have Parallel Processing Toolbox, set UseParallel to true to
% perform wrting on multiple workers
writeall(tds,outputLocation,WriteFcn=@myCustomWriter,UseParallel=false);

function myCustomWriter(coeffs,writeInfo,~)
% myCustomWriter(spec,writeInfo,~) writes mfccs to MAT files.
filename = strrep(writeInfo.SuggestedOutputName,".wav",".mat");
save(filename,"coeffs");
end