ZBar Bar Code Reader 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 EAN-13/UPC-A, UPC-E, EAN-8, Code 128, Code 93, Code 39,
Codabar, Interleaved 2 of 5, QR Code and SQ Code.

Included with the library are basic applications for decoding captured bar
code images and using a video device (eg, webcam) as a bar code scanner. For
application developers, language bindings are included for C, C++, Python 2
and Perl as well as GUI widgets for Qt, GTK and PyGTK 2.0.

Zbar also supports sending the scanned codes via dbus, allowing its integration
with other applications.

WWW: https://github.com/mchehab/zbar/