How to Cut multiple files from multiple folders in a for loop? Then return them to their own folders containing those cuts.

I have this working section that I have run all my other m files for, but i can only do it for the 12 2sec cuts of the 1st wav file under the folder directory named basson.....the Basson folder has 10 total wav files in it though.

I would like to get this for loop to work through all of the main 4 folders of wav files and slit them all up into 2sec clips,? any suggestions would help greatly!

got to have all this cut up so i can compare each data set later in program......

only other way i can think of is hard coding it, but it was going upwards of 800+ lines! ha

that line gives me files like, 3Basson1.wav, 3Basson2.wav........to 12

hopefully i worded this correctly....

Thanks again

 file_name=sprintf('%dBassoon%d.wav',3,i) %can this be changed to %d%dBassoon%d.wav, "something to increment them?",i)
 %----------------------------------------------------
 %what i have so far working for the very first of 10 wav files in that folder
 filename='C:\Users\......\Bassoon\01_AchGottundHerr_bassoon.RESYN.wav'; %does this need to be a dir?
 
[y, fs] = audioread(filename); 
k=ceil(length(y)/(2*fs));

mkdir Cut_Bassoon
% mkdir Cut_Clarinet
% mkdir Cut_Saxphone
% mkdir Cut_Violin

s=2*fs;
n = length(y);

 for i = 1: (k-1)
      
     file_name=sprintf('%dBassoon%d.wav',3,i);
        
     file_name=strcat('C:\Users\.......\Cut_Bassoon\', file_name);
     audiowrite(file_name,y((s*(i-1)+1): (s*i)),fs); % this does the actual segmenting into 2sec and sends to that dir
   
     
 end
 

Answer 1

[Paul Hoffrichter]

You can recursively find all files with a .wav extension using code from here:

https://www.mathworks.com/matlabcentral/fileexchange/31343-enlist-all-file-names-in-a-folder-and-it-s-subfolders

But without the metadata in some of the .wav files that you create, it appears that you have to handle separately the first .wav file that has the metadata from the rest that do not.

[morgan mcvay]

when you refer to the metadata, is that in reference to the 10 original sound clips i have in 4 folders?

after i cut them all into the new folders i wont have use for the originals anymore...If im understanding what you are saying, high probability im not though.

I plan on referencing the folders with the cut wav files when i do my filtering, but had just planned on doing it by reading each whole folder with all cut segments seperatly........probably not the most efficient way, but im pretty new at matlab for sound recognition algorithms!

[Paul Hoffrichter]

Metadata includes fs, which you have already extracted. Other metadata, such as the artist, you probably do not care about. But for analysis, depending about what kind of files you have, you may need to read this reference.

https://en.wikipedia.org/wiki/WAV

"The format chunk includes information such as the sample encoding, number of bits per channel, the number of channels, the sample rate."

[morgan mcvay]

Thankyou, over the past few days I have greatly increased my MATLAB performance, and i ended up taking some of the suggestions from the example code link you provided, I ultimetly used a dir search and threw then resorted them into new folder using 4 for loops.......not the most efficient! but it worked! haha

Point being, i wouldnt have figured it out without your link, so thank you.

filenameB=dir('C:\Users...........\*.wav');
filenameC=dir('C:\Users\........\*.wav');
filenameS=dir('C:\Users.........\*.wav');
filenameV=dir('C:\Users\..........*.wav');
mkdir Cut_Bassoon
mkdir Cut_Clarinet
mkdir Cut_Saxphone
mkdir Cut_Violin
for c = 1:numel(filenameC)
    Name = filenameC(c).name;
    [y, fs] = audioread(Name);
    k=ceil(length(y)/(2*fs));
    s=2*fs;
    t = 1;
    for i = 1: (k-1)
        file_name = ['Clarinet_CUT' num2str(t) '_',Name];
        audiowrite(file_name,y((s*(i-1)+1): (s*i)),fs);
        t = t + 1;
    end
end
% and repeted this 3 more times for each file.........

[Paul Hoffrichter]

Glad to have helped.