The biometric gives a normalized,
efficient and discriminating representation of feature. There are various types
of biometric recognition.
Pattern of finger print are
unique to each person. Even twins also have different finger print patterns.
This technique has some disadvantage also. Disadvantages of this system are age
of user, dryness and wetness of finger, temporary or permanent cuts on figure
can affect the performance of system because all this above things effect on
pattern hence give a poor pattern for recognition. User may go through the difficulties
in authentication process.
There are various types of facial
scan those are by capturing an image of face by using cameras or by using
infrared patterns of facial heat emission. Facial recognition generally used
for identification instead of verification. It includes eyes, nose, lips, and
so on. The advantage of this technique is that it does not require touch of any
device. The disadvantage of this technique is that the quality of capture image
depends on lightening, background, and angle of camera. And another
disadvantage is appearance of person changes time by time.
The iris is a color portion of
eye which surrounds the pupil and this portion of eye is used for recognition.
The iris pattern can be obtained through the video based images. This
technology can be used for identification and verification both. Advantage of
this recognition system is iris pattern does not change throughout the life and
it has smallest acceptance rate. But the position head and eye is very
important to get accurate results. And people should not move their head during
data acquisition. It requires a very high resolution of captured images because
iris is very small portion of eye.
This recognition uses different features of acoustics which
are different in individuals. There are various vocal qualities like frequency,
short time spectrum of dialogue and spectrograms and these are used for voice
recognition. In these type of system user selects the expression and repeat it
during identification and verification. This reduces the risk of guessing the
same phrase and entering into system.
But noise and echoes can reduce the quality and accuracy of system.
Another disadvantage of this system is voice changes illness or in different
moods and it can cause authentication problem.