Introduction

This is a really basic Java programme using jlibfprint to work with Finger Print readers.

Usage

You can enroll people and verify prints.

Enrolling

java -cp '.:JlibFprint.jar' FingerPrint enroll yourname

Verifying

java -cp '.:JlibFprint.jar' FingerPrint verify [debug]

On verification, the programme will tell you whose print was just scanned.

Debug mode is activated by adding a second parameter - the value is irrelevant.

Troubleshooting

If, on running the enroll, you get a bunch of scrolling output asking you to scan your print... it's likely that the user you're using doesn't have access to the fingerprint scanner. Try running the programme as root and, if that solves the problem, create a udev rule to give you permission to access the device. Example as follows:

On plugging in the USB fingerprint scanner, run dmesg, and get the idVendor and idProduct of the device. Note these down.

Create a group called fingerprint:

groupadd fingerprint

Add your user to the fingerprint group (user, in this case, is pi):

usermod --append -G fingerprint pi

Remember to log out and back in to the user you changed the groups of to ensure it takes effect.

Create a file called 99-usb.rules in your udev rules.d directory. In my case, /etc/udev/rules.d/

Put the following in that file, remembering to replace the idVendor and idProduct with the ones you took from dmesg:

SUBSYSTEMS=="usb", ATTRS{idVendor}=="08ff", ATTRS{idProduct}=="2580", SYMLINK+="sub20", GROUP="fingerprint", MODE="660"

Restart udev:

/etc/init.d/udev restart

Unplug and replug the USB device. With any luck, you'll be able to access it as the regular user.

Installing

Instructions are based on installing on Debian (Raspbian) on an RaspberryPi (armhf architecture). Also tested on an i386 Debian install.

I worked as a normal user named 'pi'. I'm assuming you have git and all the things you need to compile (gcc et al) as well as the Java JDK (the openjdk-7-jdk package is fine).

First install the required libraries:

apt-get install libusb-1.0-0-dev libnss3-dev libglib2.0-dev libmagickcore-dev libmagick++-dev

Make a directory under the user's home directory to do the installs into:

mkdir ~/fprint
cd ~/fprint

Clone this repository:

git clone https://github.com/phil-lavin/libfprint-java.git

Make a directory and download/unpack libfprint. Note I'm using 0.5.1 which is the latest version at time of writing. Check the libfprint site for the latest now:

mkdir libfprint
cd libfprint/
wget http://people.freedesktop.org/~hadess/libfprint-0.5.1.tar.xz
tar -xJf libfprint-0.5.1.tar.xz

Find img.c and edit it. In my case, it's at ./libfprint-0.5.1/libfprint/img.c

In img.c, find the function int fpi_img_compare_print_data and add API_EXPORTED before it such that it looks like API_EXPORTED int fpi_img_compare_print_data

Change into the unpacked libfprint directory:

cd libfprint-0.5.1

Compile libfprint. I suggest using /usr as a prefix as it has yielded less library linking headaches than the standard /usr/local:

./configure --prefix=/usr
make
sudo make install

Change back into the install directory you initially created:

cd ~/fprint

Make a directory and download/unpack Jlibfprint. Again, be sure to use the latest version from Jlibfprint's Google Code page:

mkdir jlibfprint
cd jlibfprint
wget http://jlibfprint.googlecode.com/files/Jlibfprint-0.1.tar.gz
tar -zxvf Jlibfprint-0.1.tar.gz

Change into the unpacked JlibFprint_jni directory:

cd JlibFprint_jni

Open the file Makefile for editing and find the line ADD_INCLUDES=.

You need to add 5 things here, in the same style as the example below:

1. The path to the libfprint source directory. In my case, /home/pi/fprint/libfprint/libfprint-0.5.1
2. The path from point 1 but this time as a -L param. In my case, /home/pi/fprint/libfprint/libfprint-0.5.1
3. The path to the libfprint/nbis/include directory. In my case, /home/pi/fprint/libfprint/libfprint-0.5.1/libfprint/nbis/include
4. The system path which contains jni.h (hint use the locate command). In my case, /usr/lib/jvm/jdk-7-oracle-armhf/include
5. The system path which contains jni_md.h (hint use the locate command). In my case, /usr/lib/jvm/jdk-7-oracle-armhf/include/linux

A full example of that line is:

ADD_INCLUDES=-I/home/pi/fprint/libfprint/libfprint-0.5.1 -L/home/pi/fprint/libfprint/libfprint-0.5.1 -I/home/pi/fprint/libfprint/libfprint-0.5.1/libfprint/nbis/include -I/usr/lib/jvm/jdk-7-oracle-armhf/include -I/usr/lib/jvm/jdk-7-oracle-armhf/include/linux

Now compile Jlibfprint:

make all

Copy the newly compiled binary from the dist directory to your system library path. In my case:

sudo cp dist/Default/GNU-Linux-x86/libJlibFprint_jni.so /usr/lib/

Change directory into the git checkout of this repository. In my case:

cd ~/fprint/libfprint-java

Compile the Java:

javac -cp '.:JlibFprint.jar' FingerPrint.java

You can now run the programme as per the above Enrolling and Verifying instructions.