Security is the exigent need for the tutelage of businesses and houses. There are disparate ways for securing people, property or organizations amid these techniques one is Iris detection. Iris detection technology is a bio metric technique in which the scanning or photographs of the user's iris are taken so that the person authorized to use certain facilities. Iris detection is used for security purposes and is an almost foolproof entry-level access security means because of its ability to readily identify false irises. This technology also saves you from muggers, fraud transactions and takes care of your personal data at ATM's, render national security etc.
As the cost is high, iris detection is commonly implemented only in high-security areas such as top government facilities or other places. These days applications of iris detection are increasing day by day so also applicable for many other purposes also.
Fig. Eye Structure
Bio metrics is the branch of science which leads the authentication of biological characteristics like facial recognition, DNA, retinal scanning, fingerprint ,hand geometry and iris recognition.
Iris detection is scanning a person's iris and comparing the scan to a stored photograph or template to make an identical match.
History: An endeavor
The technical brains of human have given the world, many technologies like fingerprints, facial recognition and many others. One of these is an Iris Detection technique!
The continuous striving of human minds in 1980 two ophthalmologists, Drs Leonard Flom and Aran Safir concluded that no two irises are alike, even in twins. Thus, can be used as good biometric. After numerous years in 1990 Professor John Daugman, created the mathematical
Algorithms required for digitally encoding an image of an iris to allow comparison with a real
time image. Firstly, New York Police department started with Iris detection for saving prisoner's information. Now there are about 20 companies worldwide are working on iris- recognition technology. In 2003, U.S school started installing iris detection to screen employees and parents. Then in 2010, this technique is used for making ID cards. Iris recognition remains a very active research topic in computing, engineering, statistics, and applied mathematics.
Iris Detection scans the individual, only he/she needs to stand within a defined proximity as the image is collected and analyzed. After scanning the colored portion of the eye, which is one of the most reliable biometric identifiers, the machine can analyze and compare the pattern with a previously scanned image from the library.
This is done using various processes image acquisition, iris isolation, pattern matching feature extraction and finally database creation & its validation.
Fig. Iris Detection system process
The first step taken is Image Acquisition. In this step image of the iris is taken and then various methods of processing are applied to the image to perform the many different vision tasks. During Image Acquisition focus is on high resolution and quality, moderate illumination, elimination of artifacts, image localization and adjustments for imaging contrast. Since iris is small in size and dark in colour structure so, it is difficult to obtain a high quality image.
Image Acquisition will capture the iris as part of a larger image that also contains data derived from the surrounding eye region. So you need to do Iris Isolation, i.e. removal of parts other than the iris. This process utilizes image cropping. The derivatives are ï¬ltered to be selective for horizontal information when locating the eyelid borders. There are various algorithms which use horizontal and vertical gradients in order to deduce edges in the image.
A variety of other filters can be used in order decrease the extraneous data found on the edge detection stage. While this is highly accurate the process can consume a lot of time.
Fig. Iris Detection
Pattern matching is the locating the region of an acquired image that corresponds to the iris. This matter of pattern matching can be decomposed into three parts:
1) Taking a pair of images and find the maximum deformation between them.
2) Choosing a representation of the iris patterns that makes their distinctive patterns.
3) Evaluating the best of the match between the newly acquired and data base representations.
The next step is Feature Extraction. It is done by dividing the image into basic cells. Log operator and spatial derivatives (It is the measure of how a quantity is changing in space)
of an image is calculated. Using various algorithms of feature extraction of image can be processed. This noted that it is not affected by noise due to smoothing operation.
Database creation & its validation:
In this process the information is stored in binary form (comprises of ones and zeros only). It requires efficient use of storage space. The process uses codes for two different irises are compared and will be uniquely failed when the code of an iris is compared with another version of itself. This method of validation requires all the images stored in the database to be decompressed before they can be compared to a new image. For the purpose of this project, it was decided to pursue the efficiency for space instead of speed.
An algorithm is set of rules for solving a problem in a finite number of steps, for calculating a function. In iris detection technique algorithms are used for iris encoding and detection to search databases at speeds of about a million iris codes per second, and the need for robustness against making false matches in large database searches. Algorithms are used in various processes like image isolation, feature extraction and database creation. The standard algorithms perform biometric quality assessments to detect extremely dilated pupils or excessively closed eyelids, as indicators of possible attacks. Algorithms are used for encoding and recognizing iris patterns have been the executable software used in all iris recognition systems. These are able to detect irises under various difficult conditions, like visual noise, lightning reflections or obstructions in eye images.
Most modern iris detection algorithms use random circles to determine the iris parameters. Having a starting point at the pupil, these algorithms guess potential iris centers and radii. They then integrate over the circumference in order to determine if it is on the border of the iris. While this is highly accurate the process can consume a lot of time.
Iris Detection is one of the most accurate and secure means of biometric identification while also being one of the least invasive. First, we use an iris detection algorithm to determine inner and outer layers of the iris in the image of the eye. This algorithm identifies the ring shaped outer area of the iris and pupil in the image. The image is set in the form of pixels is converted in the form of bits pattern which stores only important which can be used for detection of the image. There are various algorithms used among which the most common is about Daugman's algorithms, a Gabor wavelet transform. These algorithms form complex numbers which contain the information about the local amplitude and phase of the iris image. In Daugman's algorithms, amplitude information is not given rather phase information is good. For iris detection a photograph is developed by imaging process and iris are compared with previously stored photograph in a database. If the Hamming distance (i.e. number of bits that are different between two bit vectors) are below the decision threshold, it is a positive indication of the proper iris match.
ADVANTAGES: Makes it different!!
1) The major advantage is uniqueness. No twins can even have a same iris pattern. The patterns remain stable throughout the life.
2) The enrollment in an iris recognition system is normally quite fast. Capturing and testing of the image and administrative requirements can usually be accomplished in a couple of minutes.
3) Contact lenses do not need to be removed as they sit flush with the eye and hence have no reflections to impede the initial scan.
4) After the initial enrollment most users are able to go through subsequent scanning without any additional instruction or assistance.
5) As the speed and scalability is there so it can be used in the areas where large scale applications are required.
Fig. Iris recognition is rarely obstructed by glasses or contact
As with any technology, there are challenges, but with iris detection only few. Some of them are:
1) The iris is a very small organ to scan from far distance. Parts of the eye such as the eyelid and eyelashes continuously move which sometimes create a problem in taking an image. Person who are blind or have cataracts can also pose a challenge to iris recognition.
2) The camera used in the process needs to have the correct amount of illumination. Without this, it is very difficult to capture an accurate image of the iris.
3) Sometimes unusual lighting that may occur, causes reflections which may cause impact in capturing the proper image.
4) The system which we use in camera is currently only capturing images in a monochrome format. This results in problems with the limitations of gray scale making it difficult to distinguish the darker iris coloration from the pupil.
Fig. a) Eye without using filtration b) With Filter
1) Like all other bio metric technologies thieves are trying to use ubiquitous methods to hack or harm this technique also.
But every technology can serve as a boon or disaster-it depends on us!
APPLICATIONS: Don't Blink
Iris Detection Technology is used very much these days. The most obvious use of iris recognition technology is within the computing environment. Some of the uses are:
1) This technology is used in person's identity much reliable then documents or other identity proof's.
2) Username and password is the most common method, but sometimes difficult to maintain privacy. Now using iris detection we are able to access the systems, it's very difficult for someone to replicate an iris.
3) The technology is used in areas such as file and directory access, web site access and key access.
4) Other applications are e-commerce, healthcare in school and hospital settings, including mother-infant pairing in maternity wards insurance and brokerage transactions.
5) It is used for physical security to data centers or computer rooms.
6) It is substitute passports in automated border crossing.
7) ATM's are a major area where iris recognition is being used .It can easily replace the plastic cards and PINs.
8) It is used in making a record in jails about prisoner booking and their release.
There are innumerable applications of this technology which makes it different from others.
Fig: Iris Detection Technology used by traveler and military officers.
Keep an eye on this eye (iris) detection technology "“ it's bound to make for a fascinating debate!