Libqrencode is a library for encoding data in a QR Code symbol, a kind of 2D symbology that can be scanned by handy terminals such as a mobile phone with a camera. The capacity of QR Code is up to 7000 digits or 4000 characters, and has high robustness.
Libqrencode accepts a string or a list of data chunks then encodes in a QR Code symbol as a bitmap array. While other QR Code applications generate an image file, using libqrencode allows applications to render QR Code symbols from raw bitmap data directly. This library also contains a command-line utility to output a QR Code symbol as PNG image. This helps light-weight CGI programs.