|
Software Tips Manual:
Back
How to use the host software:
The host software was designed to
be simple and straightforward to use. It provides the necessary
communications with the hardware and the database.
Main Functions:
Our
welcome screen contains detailed information on how to use the
software and the device. It contains some help screens and troubleshooting guides.
 |
Add/Remove
User Panel: From this panel you
can add and remove users from the database.
When you press the add user button, you get a form that you fill out
with the user’s information. Also, you add a PIN number for each user, which is unique.
This PIN number is the key to identifying a user.
You then go to a Scan form, where the user enters his/her pin, then
places his hand on the device, and will get 10 readings of his/hers hand.
We decided on 10 trials, in order to get enough information for our
detection algorithm to successfully recognize the user.
To remove a user, you get a list of all the users in the system and
then click on the desired user to remove, then press the remove button and
reconfirm for deletion. |
|
Scan
Option: This tab is where
user recognition takes place. First,
a user input his/her Pin number. Then
he is told to place his/her hand on the scanner and press the scan button on
the device when ready. A scan
is produced and then compared to the databases information for approval or
rejection. |
|
Modify/View
Option: In this tab we can modify and view user database
information such as the users social security, phone, address,
finger dimension history and recognition history. The
recognition history is a good statistical data collection, were we
can observe the system's security accuracy. |
|
Options
Tab: In the options tab, the
identification administrator can choose the type of detection algorithm to
choose for the whole system. There
are two choices:
|
a.
Static Detection:
This is the easiest, but less reliable for intruder rejection,
algorithm. It basically consists on the following:
Each user is first scanned 10 times in order to have an active
database of measurements active. After
we have our ten measurements we take all of these ten results and obtain
a Medium for each finger. This
is the average of all the ten results for each finger.
We then set a standard error of 20% on each finger.
That is why it is static; you can choose the deviation percent.
When a user then scans for an approval or rejection the following
takes place: We obtain the
first fingers measurements and compare them to the medium, using a
delta+ of 20% and a delta- of 20%. If the finger result is within
bounds, then the first finger is accepted.
We then do is for the remaining three fingers with their
appropriate medium and the 20% deviation. One can observe that
some people may have more deviations to the right of the medium or to
the left. This depends on
their finger’s build. That
is why the dynamic algorithm is created.
b.
Dynamic Detection:
This diagram shows how a user has a bigger percentage on the delta- than
on the delta+ variable. This
is the key to the algorithm!!! However,
in order to produce effective results, we must have at least 50 readings
for a single user. Our
software does this automatically, since we are always keeping the 100
relevant results for each finger. In
a manner of speaking our software learns by itself.
For this algorithm, first a medium is calculated with, e.g.
50 results. We then obtain
the 8 biggest reading for a finger and discard them, and vice versa for
the 8 smallest values. We
then obtain an average of the remaining highest results and obtain a
second medium, called Delta +. We
do the same for the small values and obtain a delta -.
Now we have a dynamic scale of measurement for comparison.
This is dynamic thresholding.
With this algorithm we can now reduce our rejection error and
increase our false acceptance ratio.
Since each person will have a different scale of comparison. The
user can choose from the options menu, the percentage to discard for
each delta value. This
concludes our dynamic algorithm.
Back |