my @files = ("me~swimming.jpg" ,"J.R,ewing.jpg" , "#&%$&$=Ö-.GIF");

foreach my $file (@files)
{
	my @name_parts = split /\W{1,}/,$file;
	my $extension = pop @name_parts;
	my $newname = (join '_',@name_parts) . "\.$extension";
	print "$newname\n";
}