ZBar is an open-source C barcode reading library with C++, Python, Perl, and Ruby bindings. It is also implemented on Linux and Microsoft Windows as a command-line application, and as an iPhone application. It was originally developed at SourceForge.
ZBar is an open source software suite for reading bar codes from various sources, such as video streams, image files and raw intensity sensors. It supports many popular symbologies (types of bar codes) including EAN-13/UPC-A, UPC-E, EAN-8, Code 128, Code 39, Interleaved 2 of 5 and QR Code.
The flexible, layered implementation facilitates bar code scanning and decoding for any application: use it stand-alone with the included GUI and command line programs, easily integrate a bar code scanning widget into your Qt, GTK+ or PyGTK GUI application, leverage one of the script or programming interfaces (Python, Perl, C++) ...all the way down to a streamlined C library suitable for embedded use.
ZBar is licensed under the GNU LGPL 2.1 to enable development of both open source and commercial projects.