public static function getTransformedFilesize($size = 0, $round = 3, $dec_delimiter = ',')
    {
        $count=0;
        while ($size >= 1024 && $count < (count(self::$FILESIZE_ORDERED_UNITS)-1)) {
            $count++;
            $size /= 1024;
        }
        if ($round>=0) {
            $arr = pow(10, $round);
            $number = round($size * $arr) / $arr;
        } else {
            $number = $size;
        }
        return str_replace('.', $dec_delimiter, $number).' '.self::$FILESIZE_ORDERED_UNITS[$count];
    }