Grafika\Gd\Helper\GifHelper::_hexToAscii PHP Method

    private function _hexToAscii($hexString)
    {
        $bytes = str_split($hexString, 2);
        $string = '';
        foreach ($bytes as $byte) {
            $string .= chr(hexdec($byte));
            // convert hex to dec to ascii character. See http://www.ascii.cl/
        }
        return $string;
    }