Monitoring a directory for new files does not catch all the files

Hi all,

I need to monitor a directory for new files, specifically images, that are appearing in a specific location. In order to do this I am using simple code as below:

folder = 'path_to_directory'

imds_start = imageDatastore(folder,"IncludeSubfolders",true);

filenames = imds_start.Files;

current_files = filenames;

while true

imds = imageDatastore(folder,"IncludeSubfolders",true);

filenames = imds.Files;

new_files = setdiff(filenames,current_files);

if ~isempty(new_files)

fprintf('ONE NEW FILE')

current_files = filenames;

filename = char(new_files(end));

IMpath = strcat(folder,filename)

else

% fprintf('no new files\n')

end

end

The issue is that when files appear very quickly, some of the are not "detected". I assume that reading the file content is not the best option but this is the only one I came up with that actually works in MATLAB. Would you propose something more efficient?

Answer 1

[Voss]

new_files will contain the names of all the new files, so instead of using just new_files(end) and assuming there's one new file, use all of new_files.

if ~isempty(new_files)
    fprintf('%d NEW FILE(S)',numel(new_files))
    % now do what you're going to do with new_files (not just new_files(end))
end

[Marcin Kowalski]

yeah, simple as that! I don't know why I didn't notice this :) Thank you, it works!

[Voss]

You're welcome!