rsbar - bar code reader

DISCLAIMER: This fork is a personal side project that has the goal of translating this C-based library to Rust. It is only a hobby project and has mainly the goal to experiment, get familiar with, and practice concepts of the Rust programming language, work with Function Foreign Interfaces (FFI), and refactoring in general. It is therefore not planned to (re-)distribute this library in any way.

RSBar is a fork and migration of the ZBar Bar Code Reader library to Rust. 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 (e.g. webcam) as a bar code scanner. For application developers, language bindings are included for C, C++, and Python 2 as well as GUI widgets for GTK and PyGTK 2.0.

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

License information can be found in COPYING.

Building

See INSTALL.md for generic configuration and build instructions.

Please notice that at least autotools related packages and a C compiler are needed, in order to generate the configure script.

So, on Debian, at least those packages are needed: autoconf autopoint pkg-config libtool gcc make

If you have installed all needed dependencies, all you need to do to build the original C-based library and executables is to run:

autoreconf -vfi
./configure
make

After building the original library, you can build the rsbar library and executables using:

cargo build

The scanner/decoder library itself only requires a few standard library functions which should be available almost anywhere.

The zbarcam program uses the video4linux API (v4l1 or v4l2) to access the video device. This interface is part of the linux kernel, a 3.16 kernel or upper is recommended for full support. More information is available at:

• http://www.linuxtv.org/wiki/

pkg-config is used to locate installed libraries. You should have installed pkg-config if you need any of the remaining components. pkg-config may be obtained from:

• http://pkg-config.freedesktop.org/

Gtk Widget

The GTK+ widget requires GTK+-2.x or GTK+3.x. You will need GTK+ if you would like to use or develop a GTK+ GUI application with an integrated bar code scanning widget. GTK+ may be obtained from:

• http://www.gtk.org/

Python widgets

Python 2 legacy Gtk widget

The PyGTK 2.0/pygobject 2.0 wrapper for the GTK+ 2.x widget requires Python 2, PyGTK. You will need to enable both pygtk2 and gtk2 if you would like to use or develop a Python 2 GUI application with an integrated bar code scanning widget. PyGTK may be obtained from:

• http://www.pygtk.org/

Python 2 or 3 GIR Gtk widget

The GObject Introspection (GIR) wrapper for GTK+ widget is compatible with PyGObject, with works with either Python version 2 or 3. You will need to enable both Gtk and Python in order to use or develop a Python application with an integrated bar code scanning and webcam support. In order to build it, you need the required dependencies for GIR development. The actual package depends on the distribution. On Fedora, it is pygobject3-devel. On Debian/Ubuntu, it is libgirepository1.0-dev and gir1.2-gtk-3.0. While GIR builds with Gtk2, It is strongly recommended to use GTK+ version 3.x, as there are known issues with version 2.x and GIR, with will likely make it to fail. A test script can be built and run with: make check-gi. Instructions about how to use are GIR on Python are available at:

• https://pygobject.readthedocs.io/en/latest/

Python bindings

The Python bindings require Python 2 or 3 and provide only non-GUI functions. You will need Python and PIL or Pillow if you would like to scan images or video directly using Python. Python is available from:

• http://python.org/

Running

make install will install the library and application programs. Run zbarcam to start the video scanner. Use cargo run --bin rsbar-img <file> to decode a saved image file.

Check the manual to find specific options for each program.

dbus Testing

In order to test if dbus is working, you could use:

$ dbus-monitor --system interface=org.linuxtv.Zbar1.Code

or build the test programs with:

$ make test_progs

And run:

$ ./test/test_dbus

With that, running this command on a separate shell:

$ cargo run --features dbus --bin rsbar-img examples/code-128.png
CODE-128:https://github.com/mchehab/zbar
scanned 1 barcode symbols from 1 images in 0.01 seconds

Will produce this output at test_dbus shell window:

Waiting for Zbar events
Type = CODE-128
Value = https://github.com/mchehab/zbar

Note for WSL users: You may need to start dbus manually for this to work. All you have to do is running service dbus start.

• If it's complaining about missing permissions, run it with sudo.
• If you run rsbar-img and it throws a Name Error(Connection ":1.1" is not allowed to own the service "org.linuxtv.zbar" due to security policies in the configuration file) warning, make sure you have added the file dbus/org.linuxtv.Zbar.conf to /etc/dbus-1/system.d/). After copying the file to this directory it should work.