function removesilent(foldername)
% REMOVESILENT removes audiofiles in folder <foldername> that are silent
% (compares maximum value against small number)
% 
% by Brecht De Man at Centre for Digital Music on 15 July 2013

MIN = 0.001;
WARNING = 0.1;

list = dir([foldername '/*.wav']);
for i = 2:length(list)
    [audio,fs] = audioread([foldername '/' list(i-1).name]); 
    S = max(max(audio.^2)); % max of squared values over all channels
    if S < MIN % if empty
        delete([foldername '/' list(i-1).name]); % remove this audio file
        fprintf('''%s'' removed (maximum squared value = %f < %f).', list(i-1).name, S, MIN);
    else if S < WARNING
           fprintf('''%s'': maximum squared value = %f < %f.', list(i-1).name, S, WARNING);
        end
    end
end

end