The ZBar Bar Code Reader is a library for scanning and decoding bar
codes from various sources such as video streams, image files or raw
intensity sensors.  It supports EAN, UPC, Code 128, Code 39 and
Interleaved 2 of 5.

These are the bindings for interacting directly with the library from
Perl.

WWW: http://search.cpan.org/dist/Barcode-ZBar/