FOR VERIFICATION OF STUDENT’S IDENTITY
CASE STUDY: THE EIGENFACE APPROACH
BIOMETRIC SYSTEMS
FACE RECOGNITION
By ANYAOHA, Ekene Roy
A Project Supervised by: Dr. J. O. Hamzat
OUTLINE
AIMS & OBJECTIVES
Acquire in-depth understanding of the Eigenface approach for Face Recognition and the advantages of applying PCA to the concept
Develop an Implementation of this System in Python GUI
Solve the challenges associated with verifying Student’s identity by Human methods
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STUDENT IDENTITY VERIFICATION
IT’S
CHALLENGES
The major challenge is POINT OF ENTRY irregularities and mismanagement.
These can be observed at entries of the following:
STUDENT OR NOT?
HUMAN VS MACHINE
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WHAT IS FACE RECOGNITION?
A biometric method of identifying an individual by comparing live capture or digital image data of the individual’s face with the stored record for that individual
FACE RECOGNITION
DEFINITION
An algorithms that recognizes based on local features of individual’s face i.e. face features such as nose, eyes, ears, etc.
Examples: LFA, Gabor Wavelet
Feature base/Local region
A more generalized algorithm that considers the whole face area compared to the local region algorithm.
Examples: PCA, ICA
TYPES OF FACE RECOGNITION ALGORITHMS
Holistic approach/Global appearance
MAT 499
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EIGENFACES AND PRINCIPAL COMPONENT ANALYSIS?
The name given to a set of eigenvectors when they are used in the computer vision problem of human face recognition
EIGENFACES
also known as the eigenvectors of covariance matrix of the dataset
OR Ghostly Image
DEFINITION
PCA – Principal Component Analysis
is a statistical procedure that uses an orthogonal transformation to convert a set of observations of possibly correlated M variables into a set of values of linearly uncorrelated K variables called principal components
The number of principal components is always less than or equal to the number of original variables i.e.. K ≤ M.
Face Images
Eigenfaces
PCA – Principal Component Analysis
The Eigenfaces are defined in such a way that the first PC shows the most dominant features of the data set and each succeeding component in turn shows the next most possible dominant feature and in the process thrashes redundant features
PCA – Principal Component Analysis
as this reduction goes on, succeeding components show less “direction” and more “noise” hereby reducing the number of K eigenfaces
MXM Eigenfaces
K-Eigenfaces
K<M
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IMPLEMENTING FACE RECOGNITION IN PYTHON GUI
THE EIGENFACE APPROACH
The requirements for this implementation are as follows;
1. Mac OS/Linux and an image scanning method
2. Python GUI/Anaconda/Octave or its equivalent
3. Mat library, matplot library (matplotlib), face_rec library
The Computation & Implementation of Eigenfaces
Step 1: Obtain face images I1, I2 ... IM (Training faces) (Very important: the face images must be centered and of the same size
The Computation & Implementation of Eigenfaces
Reading Images
The Computation & Implementation of Eigenfaces
Each directory was given a unique (integer) label.
Step 2: Represent every image Ii as a vector Γi
The Computation & Implementation of Eigenfaces
Next Step: Compute the M best eigenvectors of A AT: ρi = Aνi
(keeping only the K best eigenvectors with the highest eigenvalues)
Reshaping Images
The Computation & Implementation of Eigenfaces
Recall - All Images must be (same) size.
Applying Principal Component Analysis (PCA)
Defining Subplot
For Graphical aids
It puts into consideration the list of images, a title, color scale to generate the subplot
Given an unknown face image Γ (centered and of the same size like the training faces), follow these steps:
Recognizing a Face
(where Ω and Ωl are the eigenfaces of the test image and the training set respectively)
YES
NO
(where Tl is the threshold value for each eigenfaces in training set)
NB: All new unknown faces are incorporated into the database
Comparing Test Image with Training set (Database)
Recognizing a Face
Results
Case 1: when test image matched an image in the Training set (database)
Case 2: when test Image does not match any image in the Training set (database)
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CONCLUSION AND RECOMMENDATIONS
Conclusions
Recommendations
Following the significant result prior the successful implementation of eigenfaces, face recognition is acceptable as a solution for the challenges surrounding the verification of student’s identity and should be adopted into our academic system.
The University of Lagos and others should adopt face recognition technology into their systems for easy verification of student’s identity
Can also be adopted for voter’s verification in the Elections and customer verification in banks
References
Mattew Turk and Alex Pentland “Eigenfaces for Recognition”, Journal of cognitive neuroscience volume 3, issue 1 – (1991)
Bytefish “Face Recognition with Python”, github.com/bytefish - (2012)
Thank You