public static function svg (string $text, $outfile = false, $level = QR_ECLEVEL_L, int $size = 3, int $margin = 4, bool $saveAndPrint = false, int $back_color = QR_WHITE, int $fore_color = QR_BLACK) : void
    {
        $enc = Encoder::factory($level, $size, $margin, $back_color, $fore_color);
        $enc->encodeSVG($text, $outfile, $saveAndPrint);
    }