Operation of System

In order to construct this iris recognition system (Eye – Judge), it is required to use some programming languages and some peripheral devices. We have used VisualBasic.net, SQL, Matlab and PicBasicPro programming languages to constitute software part of the project and PIC, key-pad, LCD and camera for the hardware part of the project. We have also used some programs which are Proteus and Adobe Photoshop. In order to combine system software and hardware, RS232 serial communication protocol is needed.

1 System Software

The main part of our project has been constituted by the software. The software controls database and hardware to fulfill main operating procedures. Fig.6 shows main forms of the Eye – Judge software.

Figure – 6: Main forms of Eye – Judge

1.1 Main Program (Visual Basic.net)

Visual Basic.net gives an opportunity to programmer to introduce visual interfaced program and it uses SQL database efficiently that is why we have used Visual Basic.net programming language. We have designed the program interface by using Adobe Photoshop 8 CS as shown in Fig.7.

Figure – 7: Program interface and enrolment

The main program has been written by using Visual Basic.net programming language. We have many forms in our program. Each form has been designed for different assignment. The program also has three different skins to serve user requirement which one of them (Normal Mode) is shown in Fig.8. Firstly, the eyes’ images have to be taken with the camera to build database. This procedure can be made easily by using “Enrolment” form.

Administrator has to fill required information and get passport photo to identify user. After taking passport photo, the program will alert administrator to get ten eye pictures. After getting snapshot of eye images these will be add to SQL database. Program gives ID number automatically. Administrator may enter many users without build eigenmaps after each user. Building eigenmaps will be automatically done after pressing exit button for enrolment form.

Figure – 8: Normal mode and verification form

After creating database and building eigenmaps we can make verification. It is required to run verification form for recognition. When administrator press “START” button, shown in Fig.8, the program will automatically initialize hardware by sending security codes for emergency cases and to terminate main program by RS232 interface. It will also send predefined time to predicate how long door will be open after giving access to the user. Later on, if any user come and enter his or her ID number, main program gets that specific ID from the hardware and checks whether the user is registered or not. If user is reregistered, program gets snapshot of the eye through the camera and gives access to user if user eye image meet with his or her ID. In addition, there is a simulation part for testing without using the hardware except camera.

It is also possible to remove any registered user by using “Delete User” form. After deleting the user, the program will build eigenmaps again. As you see in Fig.9, the user may be removed by entering UserID.

Figure – 9: User delete form

Administrator may reach user details by pressing “User Details” button. User details form shown in Fig.10, also gives an option to look out user logs and it is also possible to know which pictures are belonging to which user.

Figure – 10: User details form

It is required to set some values by using “Properties” form which can only be seen in normal mode. Firstly, administrator has to fix threshold value according to quality of images; it is directly related with camera, and also size of the eigenmaps. If we get sharp and high quality snapshots we may reduce the size of eigenmaps, so the program is getting faster and we can save memory and hard disk space. Also administrator has to define COM port for hardware and also has to define how long door will be open after giving access to the user.

1.2 Matlab Functions Used in the Main Program

Matlab realizes PCA procedures for iris recognition and verification. It is also an interface between camera and main program. Matlab takes snapshot of the iris image and transfers it to the main program. We have used Matlab M – Files by creating dll (eyejudgedll.dll) file for using in main program. Combination of dll with other component has been shown in Fig.11. In order to increase success of the verification we need to detect iris part of the eye image. Also iris detection has been made by Matlab. Fig.12 shows working procedure of the PCA.

Figure – 11: Operating procedure for Matlab functions

Figure – 12: PCA based iris recognition flow chart

1.3 SQL Server

SQL Server has been used to make original eye pictures secure and it is one of the fastest database program. We need to use SQL server to store original images, user detail and logs. Primary key relation of database with Eye – Judge has been shown in Fig.13.

Figure – 13: Database table relationship

1.4 Pic Basic Pro and Proteus

Pic Basic Pro is the programming language for programming PIC microchips. We have used a 16F877 PIC to scan key-pad and drive LCD. It is difficult to test written program for PIC. Programmer must program PIC each time after making any small change. In order to come over this difficulty we have used Proteus circuit designer and simulation program. It enables user to construct and test the circuit with very large component library.

2 System Hardware

In our project, we have some peripheral devices which are PIC, LCD, key – pad and camera. If you look at Fig.14, it clearly shows how main program (Eye – Judge) controls hardware of the system.

Figure – 14: Operating procedure for hardware

2.1 PIC, LCD and Key – pad

PIC is one of the most important parts of the hardware. PIC scans key-pad to get user ID to send it to main program through RS232 communication port. A LCD is included to the hardware to give guide information to the user and it is driven by the PIC. We used 4x20 dot matrix LCD. The key-pad is standard matrix form key-pad. It is working based on matrix scanning procedure.

2.2 Camera

We have used a hand camera in order to get snapshot of eye images. It is not a simple camera. We have used infrared light to predicate iris details. We have taken eye images in dark place by putting an eye hat in front of the camera because of eye surface reflects daylight and also other light. We also used fire wire cable while transferring pictures from camera to program because fire wire communication is faster than other communication types and high speed allow us to take high quality image with 720x576 resolution.

3 Working Procedure

Figure – 15: Main operation procedure

Fig.15 shows main operation procedure of the iris recognition system and Fig.16 shows details of Iris Recognition System. Firstly, the eyes’ images have to be taken with the camera to build database. Camera directly connected to computer through fire wire protocol. When the system is ready after building database, the main program sends security, program terminate code and delay time to describe how long the door remains open. Security code is required to open door manually if any problem occur on PC or server. Terminate code is required to send key command to main program if we need to stop the system because programmer may change security codes or add/remove any other user.

Figure – 16: Data flow diagram of iris recognition system

After initializing hardware, the system is ready to make verification. The procedure starts with entering ID number by the user using key-pad. ID number automatically is sent to main program by PIC through RS232 serial communication protocol. Until this moment, main program always checks serial port whether new ID number is entered or not. The main program checks ID number from the database whether it is a registered user or not. If the user do not registered before to get access, program sends an error code to PIC and PIC prompts to user “You are not a registered user” by using LCD. If the user has a registered ID, program prompts user to make a closer look to the camera and press a snapshot button when he or she is ready to give a eye photo. After pressing button to take snapshot, PIC sends a command to main program to take snapshot. Eye photo is converted to iris form by making iris detection. After this point main program realizes PCA procedure to compare taken picture to verify. If PCA procedure verifies the snapshot iris picture, it sends a command to PIC to give access. Getting access command from the main program starts new procedure for PIC. It sends a control signal to the door and door be remain open until defined time limit reach. If access not granted by the main program it sends a command to PIC and PIC will prompt user to “Access Denied” through the LCD.

This operation procedure continues until any security code entered. Administrator user may control the door by entering security code. If security code is entered door opens and remain open until “*” button pressed from the key-pad.