 <p>The <a href="http://code.google.com/p/zxing" rel="nofollow noreferrer">zxing library</a> is primarily Java, but, includes a <a href="http://code.google.com/p/zxing/source/browse/#svn/trunk/cpp" rel="nofollow noreferrer">port of the QR Code detector and decoder to C++</a>. </p>