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Physiological response to light
Ease of registering its image at some distance
2 IRIS FEATURE AND PROCESS
There are verities of features that can be used to
distinguish one iris from another. One of the main
characteristics is the trabecular meshwork, a tissue
which gives the appearance of dividing the iris in a
radial fashion that is permanently formed by the
eighth month of gestation. During the development
of iris there is no genetic influence on it, a process
known as chaotic morphogenesis that occurs during
the seventh month of gestation, for which identical
twins have four different irises. The iris is protected
behind the eyelid and cornea unlike other biometrics
such as fingerprints or face, the chances of damage
is minimal or nil. The iris is not a subject to be
change with age, it means its pattern remain stable
till death. Generally, the process of iris recognition
system includes the following steps:
Image Acquisition
Iris Localization
Image Optimization
Comparison
The image of iris can be captured using a
standard camera using both visible and infrared light
and may be either a manual or automated procedure.
In manual procedure, the user needs to adjust the
camera to get the iris in focus and needs proper user
training to be successful. The automated process
uses a set of cameras that locate the face and iris
automatically. Once the camera has located the eye,
the image is thenanalyzed to identify the outer
boundary of the iris, the pupillary boundary and the
center of pupil. This information is used to produce
a vector record called iriscode. This record is then
stored into a database for future comparison.
3 RELATED WORK
Daugman’s work: the visible texture of a person’s
iris in a real-time video image is encoded into a
compact sequence of multi-scale quadrature 2-D
Gabor wavelet coefficients, whose most-significant
bits comprise a 256-byte iris code (J. Daugman,
“How Iris Recognition Works”)(J. Daugman, Nov
1993)(J. Daugman, Dec 2001).
Wildes’ work: is very similar to the above-
mentioned method. A laplacian pyramid is used to
apply a 2-D transformation. A match value is
calculated for the four bands through spatial
correlation (R. Wildes, Sept 1997).
Boles’ work: based on calculating the zero-
crossings representations of the wavelet transform.
These representations are stored as templates and are
used for the matching algorithm (W. Boles, 1997).
4 THE PROPOSED SYSTEM
This system is divided into these parts:
A. Image Acquisition: This is the stage of acquiring
the eye image using digital camera.
B. Iris Localization: Finding the boundary between
the pupil and the iris, the outer boundary of iris and
the center of the pupil.
C. Polar Transformation: Using the center and the
radius we find a polar coordinate system. In this
system the feature of the iris is extracted.
D. Identification: Using linear discriminant analysis
we found a match for the acquired iris feature.
E. Verification: Using cross correlation method it
verifies the identified image to get efficient search
result.
A. Image Acquisition
The iris is a relatively small (1 cm diameter),
dark object and that human operator are very
sensitive about their eyes, this matter requires
careful engineering. The following points should be
concern:
Describe to acquire images of the iris with
sufficient resolution and sharpness to support
recognition
It is important to have good contrast in the
interior iris pattern without resorting to a level of
Illumination that annoys the operator
The image should be well framed (i.e. centered)
Noises in the acquired images should be
eliminated as much as possible
A COST-EFFECTIVE IRIS RECOGNITION SYSTEM USING LINEAR DISCRIMINANT ANALYSIS AND
CROSS-CORRELATION TECHNIQUES
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