A Finger Print is an
impression of the friction ridges of all or any part of the finger. A
friction ridge is a raised portion of the epidermis on the palmar (palm
and fingers) or plantar (sole and toes) skin, consisting of one or more
connected ridge units of friction ridge skin. These ridges are sometimes
known as "dermal ridges" or "dermal papillae".
Identification
Finger Print identification
(sometimes referred to as dactyloscopy) is the process of comparing
questioned and known friction skin ridge impressions from fingers to
determine if the impressions are from the same finger. The flexibility
of friction ridge skin means that no two finger or palm prints are ever
exactly alike (never identical in every detail), even two impressions
recorded immediately after each other.
Finger Print identification
(also referred to as individualization) occurs when an expert (or an
expert computer system operating under threshold scoring rules)
determines that two friction ridge impressions originated from two
fingers are entirely different.
Finger Prints are unique
property of any human being and can be used to identify who is who. It
can help industries in many ways, in form of Recognition and Access
Control solutions.
Finger Print Recognition
Algorithms
A Finger Print recognition
algorithm is a method of identifying a person using his/her
Finger Prints. Currently, the most frequently used Finger Print recognition algorithms are:
§ Characterization
algorithm
The
characterization algorithm evaluates the quality of Finger Print images
acquired by the Finger Print recognition sensor to determine their
usability, and analyzes the character points of the Finger Prints. This
is the most frequently used Finger Print recognition algorithm.
§ Finger Print -matching
algorithm
The
Finger Print -matching algorithm is a process of arranging two comparable
Finger Prints to analyze their common characteristics, and calculating
the degree of similarity between the two Finger Prints.

BioAXS Algorithms
The Finger Print recognition algorithm follows the
commonly accepted Finger Print identification scheme, Characterization
algorithm which uses a set of specific Finger Print points (minutiae).
However, it contains many proprietary algorithmic solutions, which
enhance the system performance and reliability. Some of them are listed
below:
The adaptive image
filtration algorithm:
It allows
to eliminate noises, ridge ruptures and stuck ridges, and extract
minutiae reliably even from poor quality Finger Prints, with a processing
time of about 0.2 - 0.4 seconds (all times are given for a Pentium 4, 3
GHz processor).
§ Functions can
be used in 1:1 matching (verification), as well as 1:N mode (identification).
- Algorithm includes a fast template matching algorithm that is tolerant
to Finger Print translation, rotation and deformation.
§ Algorithm does not require the presence of the Finger Print core or delta
points in the image, and can recognize a Finger Print from any part of
it.
§ Algorithm
can use database entries which were pre-sorted using certain global
features. Finger Print matching is performed first with the database
entries having global features most similar to those of the test
Finger Print . If matching within this group yields no positive result,
then the next record with most similar global features is selected, and
so on, until the matching is successful or the end of the database is
reached. In most cases there is a fairly good chance that the correct
match will be found at the beginning of the search. As a result, the
number of comparisons required to achieve Finger Print identification
decreases drastically, and correspondingly, the matching speed
increases.
§ Algorithm
has the Finger Print enrollment with features generalization mode. This
mode generates the collection of the generalized Finger Print features
from a set of Finger Prints of the same finger. Each Finger Print image is
processed and features are extracted. Then the features collection set
is analyzed and combined into a single generalized features collection,
which is written to the database. This way, the enrolled features are
more reliable and the Finger Print recognition quality considerably
increases.
§ Algorithm modes that help to achieve better results
for specific scanner. Modes are following:
o Universal
o DigitalPersona
U.are.U family scanners
o Cross
Match Verifier 300 scanners
o Futronic
FS80 scanner
o NITGEN
Fingkey Hamster and Fingkey Hamster II scanners
o SecuGen
Hamster III scanner
o Testech
Bio-i scanner
o Startek
FM200 scanner
o Tacoma
CMOS scanner
o Fujitsu
MBF200 scanner
o Identix
DFR-2090 scanner
o UPEK
TouchChip scanners
o Digent
Izzix FD1000 scanner
o BiometriKa
FX 2000 and FX 3000 scanners
o AuthenTec
AES2501B sensor
o AuthenTec
AES4000 and AF-S2 sensors
o LighTuning
LTT-C500 sensor
o Atmel
FingerChip sensor
Algorithm technical
specifications
|
Required
Finger Print resolution
|
>
250 dpi
500 dpi recommended
|
Finger Print processing time
|
0.2 -
0.4 seconds
|
Matching
speed *
|
40,000
Finger Prints/second
|
Size
of one record in the database **
|
150
bytes - 1.8 Kbytes
(configurable)
|
Maximum
database size
|
unlimited
|
|