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					                                                                           Le, Wilson
                                                                            Coen 150
                                                                             2/22/05

                        Research Paper on Facial Recognition

       After the terrorist attacks of September 11 th security has become of
greater concern for many Americans. One of the biggest ways to
improving our security is to be able to identify a person so that we can
distinguish an authorized user from an unauthorized user. There are a
number of ways that a security system can confirm that someone is an
authorized user, but most security systems nowadays are looking for
three main things. The first thing they look for is something you have;
this can be something like a token or a smart card where a machine has
to read data from your card before granting or denying you access into a
building or secured area 1. But the problem with this is that something you
have really means something you might lose or something you might
forget at home. Another thing that security systems look for would be
something you know which usually involves typing in a password to log
onto a secure network. Like many things there is also a drawback to
passwords and that is simply because of the fact that people tend to
forget their passwords. Finally, the third way for a computer system to
identify a person is through something they are, this usually entails the
use of biometrics. Biometrics is a way to identify a person’ identity or
authenticate them using their biological traits. Biometrics can include
fingerprints scans, iris scans, signature verification and also facial
recognition.
       Only until recent has there been a need for biometrics, this need
mainly came from companies looking for a more advance security
precaution. This is fact is also evident from recent market trends, which
show biometrics constantly growing from the $6.6 million in 1990 to the
$63 million in 1999, according to the U.S National Biometrics Test Center
in San Jose 2. Cahners In-Stat Group has even gone further to predict that
sales of biometrics will reach $520 million by 2006 2 .

Other type of Biometrics


1
  Jonathan G. Gossels, Matthew Martin. Should You Care About Biometrics?
http://www.systemsexperts.com/
2
  Emelie Rutherford. Facial-recognition tech has people pegged.
http://archives.cnn.com/2001/TECH/ptech/07/17/face.time.idg/
        One of the most widely used types of biometrics today is the use of
fingerprints as a form of identification. In the same way that a tire on a
car has rubber ridges to grip the road, fingers have ridges of skin which
allows us to more easily grip things. These ridges of skin on our fingers
can also act as sort of a built in identity card that can easily be
accessible. These ridges on our fingers form from a combination of
environmental factors and genetics 3. The skin forms from the general
orders of the DNA code but the particular way that it forms comes from
the outcome of random events like the exact position of the fetus in the
womb at a particular moment, the exact makeup and density of the
surrounding amniotic fluid can all decides how every individual ridge on a
person’ finger will form. Consequently, because of the immeasurable
environmental factors influencing the formation of a person’s finger, there
is virtually no chance of the same exact finger print pattern forming on
two separate individuals. This fact alone allows fingerprints to be one of
the most widely used forms of identification.
        The way a fingerprint scanner system works can be broken up in
two steps. First, the system has to be able to scan or obtain an image of
your fingerprint. Second, it then has to compare the ridges and valleys of
the new image with the image of your fingerprint that has been
previously scanned and saved onto a database. Although there are a
number of ways that a fingerprint can be scanned the two most common
ways are through the use of an optical scanner, which uses light and a
charge coupled device (CCD) to take the picture of a fingerprint 3 . The
second method uses capacitance scanners which uses an electric current
to sense the fingerprint. Once the image of the fingerprint is scanned,
specific feature of the fingerprint called minutiae is compared using highly
complex algorithms to recognize and analyze the minutiae. Comparison of
the fingerprints can be thought of as basically measuring the relative
positions of the minutiae in the same way you would recognize various
parts of the sky by the relative positioning of the stars. Then to obtain a
match, the system has to find an adequate number of minutiae patterns
that the two prints have in common which will fluctuate according to the
scanning program.
        Another type of biometric that is used for verification of an
individual’s identity is through the use of iris scans. Iris scans is a great
biometric for many reason, one is because of the fact that no two people
have the same iris and in addition the two irises on an individual are also

3
 Tom Harris. How Fingerprint Scanners Work. http://computer.howstuffworks.com/fingerprint-
scanner.htm/printable
unique. Also irises contain thousands of features like arching ligaments,
furrows, ridges, crypts, rings, corona, and freckles which can all be used
to make a so-called reference template for that particular eye 10 .
Furthermore, because there are so many features that can be included in
a reference template for a particular iris the false acceptance and
rejection are extremely unlikely. With new technology coming out that
can detect muscle movement due to lighting within the iris, these systems
would now be able to differentiate between a living iris and an artificial
one. These are just some of the many reasons why using the iris as a
biometric is one of the best choices for verification of a person’ identity.
       With new technology constantly coming out each day, biometric
systems are now capable of verifying a person’ identity by their signature,
systems like theses are often referred to as dynamic signature verification
(DSV)4 . With a specially designed pen and tablet, DVS systems are
designed to capture characteristics like angle of the pen, speed at which
the signature is written, number of times the pen is lifted during the
signature, pressure exerted on the tablet, and also variations in the speed
during different parts of signing are all taken as the person signs their
signature. Combining all this information together about a person’
signature allows for the creation of a biometric trait which can be used by
a security system to identify a person. Since variations often occur each
time a person signs their name, more than one sample of a signature
must be taken. Next, the average of the data is taken for each of the
different characteristics which is then stored in a database that is used
during the comparison process when a person uses the signature
authentication system.

Why Facial Recognition?

       When discussing the ways of identifying a person’s identity we
must go back to the basics, to the ways in which were identifying people
since we were born, and that is through facial recognition. Using facial
recognition as a biometric basically means the use of one’s face as a tool
to verify the identity of that of that person. Although other types of
biometrics such as iris scanning are more accurate than facial recognition
which has about a one percent error rate, facial recognition will most
likely be the more commonly accepted type of biometric because of the
fact that it is not intrusive, or in other words, it is a form of passive



10
  Paul Rosenzweig, Alane Kochems, Ari Schwartz. Biometric Technologies: Security, Legal, and Policy
Implication. Legal Memorandum. No12. June 21, 2004.
surveillance 4. It does not require the person to walk up to a machine and
put their eye into a hole so that it can take a picture of their iris nor does
it require them to stop to sign or type in something into a computer. Also,
for companies that have security cameras already in place and picture of
all the employees already on file, often they would not need to install
anything beyond new software which is obviously more inexpensive than
installing a whole new system with checkpoints for an iris scanning setup.
As director of corporate communications at Visionics Frances Zelazney put
it “unlike other biometrics, facial recognition provides for inherent human
backup because we naturally recognize one another 2 .” In addition
Zelazney stated that if the facial recognition system fails or goes down,
you can just pull up an Id with the employee picture as a backup,
something that wouldn’t be applicable with other biometrics like iris scans
and fingerprint devices 2 .
        Additionally, facial recognition systems can also reduce the user
frustration. For example, if you’re in a large company that has security as
one of their top priorities then it would not be uncommon for a user to
have upwards of a dozen different passwords since these companies
would institute standards to ensure high quality passwords that will also
need to be changed on a regular basis 1 . This would then lead to users
forgetting their passwords and time off work spending at the IT
(Information Technology) office trying to reset their forgotten password
can be enormous. User will be frustrated because they would have to
remember all these complicated passwords that can they can easily forget
while the companies would also be upset because of all the time lost from
work. The use of facial biometrics would prevent all this from happening
and would make life for the user so much more simple since the only
thing the user would have to do is basically show up for work so that the
cameras can see and authenticate him. As you can see one of the main
reasons why facial recognition stands out from the other types of
biometrics is that it’s a passive surveillance tool, in that a user walking
down a hall can be granted or denied access to a secure area even before
they reach the door.

How Facial Recognition Works


5
 Laura Behrens, Gartner. Biometrics: Helpful, but not a cure-all. http://news.zdnet.com/2100-9595_22-
870372.html
1
    Jonathan G. Gossels, Matthew Martin. Should You Care About Biometrics?
2
     Emelie Rutherford. Facial-recognition tech has people pegged.
        Facial recognition software is established on the capability to first
recognize faces and then measure various features of each of the face.
For instance, there are certain distinguishable landmarks on each person’
face, the combination of these peaks and valleys are responsible for the
different makeup of each human face and their features. Visionic, a
leading developer in facial recognition technology defines these features
or landmarks as “nodal points 2”. While there are about eighty nodal
points on a human face, Visionics’ FaceIt facial recognition software only
needs 14-22 of them for the facial recognition software to complete its
detection process says Zelazney. Some of the nodal points used by FaceIt
facial recognition software are the distance between the eyes, the width
of the nose, tip of nose, depth of the eye sockets, cheekbones, jaw line,
and chin. FaceIt software uses these 14-22 nodal points to concentrate
on what is called the golden triangle which runs from temple to temple
and just over the lip. By concentrating on the more stable inner region of
the face FaceIt is able to recognize people who have grown a beard, put
on glasses, gain weight, or aged.
        Facial recognition works in that it first need to captures a picture of
a person to analyze. To capture an image, the recognition software will
search the field of view of the video camera for a face. A multi-scaled
algorithm is used to search for faces and once a head like shape is in
view of the camera, it is then detected within a fraction of a second. After
the head like shape is detected the system will then switches to a high
resolution search. After the detection process is completed the system
then ascertains the position of the head, its size, and pose. Also, in order
for the system to recognize the face, it must be turned at least thirty-five
degrees towards the camera. Next the photograph of the head is rotated
and scaled so that it can be mapped into a suitable size and pose. This
step if often referred to as “Normalization” and is performed despite the
distance and location of the head from the camera. Furthermore, light
has no bearing on this process.
        Once the normalization process is done, the system will then need
to convert the data from the face into a unique code, this is considered
the heart of many facial recognition systems. Visionics’ FaceIt systems
uses a Local Feature Analysis (LFA) algorithm which plots the relative
positions of certain nodal points and comes up with a unique long string
of numbers and creates what is called a “faceprint” for that particular
face6 . By creating the faceprint the system can now more easily compare
the new faceprints with the facesprints store in the database. As

2
  Emelie Rutherford. Facial-recognition tech has people pegged.
6
  Kevin Bonsor. How Facial Recognition Systems Work. http://computer.howstuffworks.com/facial-
recognition.htm/printable
comparisons are being made with the faces in the database, each
comparison is assigned a value on a scale of one to ten by the system
with ten being 100% match. If a score is above a predetermined
threshold (usually 8) then a match is declared. As matches in the
database are found an operator will then double check the two pictures to
make sure that the computer has made a correct match.

Applications for Facial Recognition

       The fact that facial identification systems is a form of passive
surveillance, and that it is relatively cheaper to implement than many
other biometric systems, facial recognition systems are more widely being
used. For example, Visionics Corp. of Jersey City, N.J., gain widespread
attention after its FaceIt system was installed by Tampa police. The
Tampa Police department was loaned the system for one year in order to
match images of captured by dozens of camera in an entertainment
district against digital mug shots of known criminal. These 36 camera
positioned in different areas of the crowded streets of Ybor City have
allowed police to keep a closer eye on the generally activity. Also in
January of 2000 Tampa Bay police were able to use the FaceIt at Super
Bowl XXXV to conduct what is called the biggest police line up in history 6 .
Officers were able to use the FaceIt to get snapshots of faces from the
crowd and match them against a database of criminal mug shots.
       There have also been many broad applications for facial recognition
systems similar to Visionics’ FaceIt. These identification systems are even
finding their way into Casinos which finds them useful for scanning their
premises for known cheats. FaceIt surveillance system has even be added
to Keflavik International Airport in Iceland close-circuit television as a
security measure which allows them to search for terrorist. Facial
recognition is also being used by Motor Vehicle officials in West Virginia
to scan databases of driver license pictures for duplicates and frauds.
Israeli official have also used Visionics’ FaceIt software to monitor and
manage the flow of people entering and exiting the Gaza Strip.
       In Britain in 1999, London Borough of Newham police installed
some 300 camera to search for known criminals. Authorities there have
credited the 34% drop in crime to the facial recognition system 7 .
       Facial identification systems have also been known help eliminate
voter fraud. For instance, to influence an election many people will
register several times under false alias so that they can vote multiple

6
 Kevin Bonsor. How Facial Recognition Systems Work
7
 Robert O’Harrow Jr. Matching Faces With Mug Shots. http://www.washingtonpost.com/ac2/wp-
dyn?pagename=article&contentId=A12629-2001Jul31&notFound=true
times. This problem has led to once of the most innovative use of the
facial recognition systems, which was used by the Mexican government in
the presidential election in 2000 to eradicate duplicate voters. Official
here can search through the digital photos in the voter database for
duplicates at the registration time by comparing images of the person
registering to the images that have already been on file to catch those
who try to register twice. Facial recognition programs can even be used
for home purposes. Adding a webcam to your home computer and
installing facial recognition software can allow the user to use their face
to log into a computer instead of typing in a password. This type of
technology has even been integrated into IBMs’ screensaver for the A, T,
and X series of Thinkpad laptops.
        Additionally, since 1998 Visionics has received about $800,000 each
year as part of a project by the Justice Department in order to come up
with a way to search Internet pornography sites for images of exploited
and missing children 7 . In 2001 West Virginian official started to using the
newly developed software to perform these types of searches on the
Internet.
        There has also been much talk about potential applications for
facial recognition systems. To illustrate, facial recognition systems can be
used in ATM (Automated Teller Machine). The facial recognition software
can speedily verify a customer’s face. After the FaceIt system creates a
faceprint of the user, it can then be used to protect the customer against
fraudulent transaction and even identity theft. With banks using facial
identification to help identify ATM users, there wouldn’t be a need for
photo IDs or personal identification number (PIN) anymore since
identification would be verified by the system6 . As evident from the above
examples more and more people are adopting facial recognition as a
means to verifying the identity of a person. It would also seem true that
only good would come from these facial recognition systems in that they
are designed to take criminal off the our streets, secure our airports,
secure our computers, and also help in locating missing kids on the
internet. So why aren’t more identification systems like FaceIt being
used?

Reasons against the Use of Facial Recognition

Although it seems that there are many advantages in using facial
recognition, there are many people who are opposed to the use of this
kind of software. One of the reasons against facial recognition is that fact

6
    Kevin Bonsor. How Facial Recognition Systems Work
7
    Robert O’Harrow Jr. Matching Faces With Mug Shots.
that it has a one percent error rate for matches. This one percent can
lead to at least one terrorist boarding any full commercial jet and the
figure only grows when with dealing with a jumbo jet. Additionally, this
one percent false positive rate could lead to at least one innocent person
on every flight being wrongly identified as a criminal or suspicious person.
If you look on a bigger scale, this one person per flight false positive rate
would mean that thousands of people would falsely be identify as a
suspicious character which could then lead to thousands of angry
customers. Moreover, out of date photos, poor lighting, and poor quality
photos in the database can all add to the number of misidentifications. To
some all these factors combine together can lead to thousands of people
being falsely identified which would then out way the profit and thus
causing the identification tool to be deemed effective.
        Another argument against the use of facial recognition software is
the fact that many believe that although this type of tool is design to
protect our privacy, it will in the end invade our privacy. To illustrate,
facial recognition could easily be used by the operator to take your
picture when you are entirely unaware of the camera, it can also easily be
used as a tool for spying on citizens as they move around in these public
places. There are also those that are concerned that state government
might try to implement facial recognition and other biometric technology
into the Department of Motor Vehicles (DMV) identification system which
would then result in a national identification system.
       Also according to the American Civil Liberties Union (ACLU) the
FaceIt system that was installed in Tampa, Florida didn’t improve our
safety. Systems logs revealed many false matches between those
photographed by police camera and mug shots of those on the
department’s database. It was also reported by the ACLU that the FaceIt
software often times matched male and female subjects and people with
considerable differences in age and weight 8 . Not only is the ACLU the only
people against the FaceIt software, even people like House Majority
Leader Dick Armey, R-Texas, have went on to publicly insist Tampa Police
Department to stop the use of the FaceIt software, citing that it was too
invasive9 . Even some of the residents from Tampa have gone onto protest
against the Facial identification system, as evident from the protest stage
on a Saturday by about one hundred masked protesters who compared
the Visionics’ face recognition system to “Big Brother 9 .” As with any type
of controversial products in he market there comes a great amount of

8
  Stephanie Olsen. ACLU decries face-recognition tools. http://news.zdnet.com/2100-9595_22-
800685.html
9
  Lane DeGregory. Click. BEEP! Face captured.
http://www.sptimes.com/News/071901/Floridian/Click_BEEP_Face_captu.shtml
opposition which is apparent here for the facial recognition software.
When dealing with security and surveillance there is a fine line between
security and privacy, where too much security or surveillance can land
you on opposite side with the ACLU, while too much privacy can lead to
you product being ineffective.


Conclusion

       The events of 9/11 have lead to an increase in security or the need
for more security. As companies look for a new method to authenticate
user, one realizes that passwords are becoming harder and harder to
remember. While smart cards are constantly being lost or left at home,
authentication by biometrics seems to answer the our call. Biometrics like
iris scan, fingerprint scans, signature verification, and facial recognition
all seem to make our life easier since we don’t have to remember
anything password or keep anything on our person at all time, there user
basically isn’t require to do much. With iris scans you have to put your
eye up to a machine to be scanned, while for signature verification you
have to sign your name on a tablet. Even small tasks like these can be
too time consuming when dealing with a high volume of people. Yet for a
facial recognition system this is not a problem since you face can be
scanned and authenticated before you even reach the secured area.
Facial recognition can be use for numerous amounts of applications like
eliminating voter fraud, eliminating the use of pin and photo IDs at the
bank, it can be a security precaution for your computer, it can help to
search internet pornography sites for missing kids, it can help to secure
out streets by being able to pick out known criminal out of a large crowd.
Yet with the potential that comes with facial recognition there too are
many drawback to this. The main one being that it can be used to
infringe on your privacy rights. So the main question here is how much of
your privacy are you willing to give up in return for security? Once you
figure that out, will you still have a product that is effective and not
intrusive? After I doing all the research and reading for this topic I have
come to conclude that there will never be a product that will meet all of
these criteria’s, in order for security system to effectively work we must
give up some of our civil liberties whether it be time or privacy.
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