International Journal of Engineering Trends and Technology (IJETT) – Volume 4 Issue 9- Sep 2013 An Improved Face Detection and Recognition Method Based On Information of Skin Colour for Security System Srivalli P#1, B Karunaiah*2, K V Murali Mohan*3 1 2 Srivalli P, pursuing M.Tech (ECE) from Holy Mary Institute of Technology and science (HITS), Bogaram, Keesara, Hyderabad. Affiliated to JNTUH, Hyderabad, A.P, INDIA B Karunaiah, working as a Professor (ECE) at Holy Mary Institute of Technology and science (HITS), Bogaram, Keesara, Hyderabad. Affiliated to JNTUH, Hyderabad, A.P, INDIA 3 K V Murali Mohan, working as a Professor and HOD (ECE) at Holy Mary Institute of Technology and science (HITS), Bogaram, Keesara, Hyderabad. Affiliated to JNTUH, Hyderabad, A.P, INDIA Abstract— In lot of areas, unauthorised entry is prohibited to have an assurance that something valuable is not stolen. This paper employs two of the emerging technologies- Digital Image Processing and Embedded Systems to develop a prototype so that the door can be unlocked only by recognising the faces of authenticated persons. The electronic Embedded Systems which consists of a camera, is interfaced with the PC for capturing and processing images. Keywords— Eigen faces, Templates, Face Segmentation, Gabor filters. I. INTRODUCTION Security is an important feature in all environments. Security relates to protection of anything from unwanted people. Safety is one of the elements that complete one’s requirement for a meaningful life that leads to selfactualization [1, 2, 3, and 4]. Deeming all the many ill fated cases connected to security lapses in organizations, the effortlessness and benefits of computer based security devices has brought the use of computer controlled security door systems in the modern vocabulary. Recent research works have shown that diverse human characteristics like finger prints and voice tags have been used for the development of an automated security system but further studies have revealed that a Sophisticated Security System can be developed using facial recognition systems. Face recognition is a famous image processing techniques for bio-metric based security system and humans frequently use faces to recognize individuals and improvement in ISSN: 2231-5381 computing capability over the last few decades now enable similar recognitions automatically. Earlier the face recognition algorithms used plain geometric models, but the recognition process has now changed into a science of complicated mathematical representations and matching procedures. The new research and proposals in the past ten to fifteen years have driven face recognition technology into the focus. Face recognition can be used for both verification and identification. Above all computational models of face recognition are appealing because they can contribute not only to theoretical insights but also to practical applications. Unfortunately, developing a computational model of face recognition is quite difficult, because faces are intricate, multidimensional and motivation for important visual factors. They are a natural class of objects, and stand in severe contrast to sine wave gratings, the “blocks world,” and other artificial stimuli used in human and computer vision research [5]. Thus unlike the majority of early visual functions, for which we may build-up a full representation of retinal or striate behaviour, face recognition is a high level task for which computational approaches can at present only suggest broad limitations on the corresponding neural activity. In some research works, an associative network with a simple learning that could classify face images and recall a face image from an incomplete or noisy version input to the network was described [6 and 7]. Our approach is based on an information theory approach that decomposes face images into a small set of characteristic feature images called http://www.ijettjournal.org Page 3851 International Journal of Engineering Trends and Technology (IJETT) – Volume 4 Issue 9- Sep 2013 ‘Eigenfaces’ which are actually the principal components of the initial training set of facial images. Recognition is accomplished by projecting a new image into the subspace spanned by the Eigenfaces (‘face space’) and then classifying the face by comparing its position in the face space with the positions of the known individuals. Eigenfaces are the Eigen vectors which are representative of each of the dimensions of this face space and they can be considered as facial features. A face can be represented as linear function of the singular vectors of the set of faces, and then singular vectors are eigen vectors of the covariance matrices. Generally, face recognition techniques is divided into two groups based on the face representation they use: 1) Appearance based uses holistic texture features and is applied to either whole face or specific regions in a face image. 2) Feature based uses geometric facial features (mouth, eyes, cheeks etc.) and geometric relations between them. Among many approaches to the problem of face recognition have been proposed, subspace analysis based on appearance is one among the oldest, and even so it yields the most encouraging results. Subspace analysis is executed by projecting an image into a lower dimensional space and after that recognition is performed by measuring the distance between known images and the image to be identified. The most difficult part of such a system is finding a subspace. II. EIGENFACE APPROACH A. Eigen Values and Eigen Vectors In linear algebra, the eigen vectors of a linear operator are non-zero vectors which, when operated on by the operator, give a scalar multiple of them. The scalar is then called the Eigen value (λ) associated with the Eigen vector (X). Eigen vector is a vector that is scaled by a linear transformation. This is an inherent property of a matrix. Whenever a matrix operates on it, only the magnitude of the vector is changed but the direction remains the same = Where A is a vector function. Calculation of Eigen Values and Eigen Vectors By using the above equation ISSN: 2231-5381 ( − ) =0 Where I is the n x n identity matrix. From fundamental linear algebra it is clear that a nontrivial solution exists only and only if ( − )=0 Where det denotes determinant. When evaluated, it becomes a polynomial of degree n. This is known as the characteristics equation of the matrix A and the corresponding polynomial is known as characteristics polynomial. Thus there are n eigen values of A satisfying the equation AXi=λXi Where i=1, 2, 3...n. In the case where there are r repeated eigenvalues, then a linearly independent set of n eigen vectors exist, provided the rank of the matrix (A-λI) is rank n-r. Once the eigen values of the matrix has been found, eigen vectors can be found by Gaussian elimination. III. PCA A. .Overview of the PCA algorithm: The algorithm for the facial recognition using eigenfaces is basically described First, the original images of the training set are transformed into a set of eigenfaces E. Later; the weights are calculated for each image of the training set and stored in a set W. After observing an unknown image X, the weights are evaluated for that specific image and stored in the vector WX. Later, WX is compared with the weights of images, of which we certainly have knowledge that they are facing (the weights of the training set W). One method of achieving this would be to regard each weight vector as a point in space and calculate an average distance between the weight vectors from WX and the weight vector of the e image WX. If this average distance exceeds some threshold value , then the weight vector of the test image WX lies too ”far apart” from the weights of the faces. In this case, the test image X is considered to not a face. Otherwise (if X is actually a face), its weight vector WX is stored for further categorization. The optimal threshold value has to be calculated empirically. By using PCA we can transform each original image of the training set into a corresponding Eigen face. A significant property of PCA is that we can reconstruct any original image from the training set by combining the Eigen faces. Talking of Eigenfaces, we can say that they are nothing less than http://www.ijettjournal.org Page 3852 International Journal of Engineering Trends and Technology (IJETT) – Volume 4 Issue 9- Sep 2013 characteristic attributes of the faces. So we can say that the original face image can be reconstructed from Eigen faces. IV. Significance of Eigenface Approach: We have seen the standard Eigenface Approach for Face Recognition. In this work, we find out M Eigenvectors corresponding to training set images. Now choosing only M' Eigenvectors from these M Eigenvectors is the most important task. This selection is done in a way such that M' is less than M, to symbolize face space spanned by images. This will diminish the face space dimensionality and increase speed of face recognition. We can choose only M' Eigenvectors with maximum Eigen values. Now as the higher Eigen values represent maximum face variation in the corresponding Eigenvector direction, considering this Eigenvector for face space representation is important. As the lower Eigen values do not provide much information about face variations in corresponding Eigenvector direction, these small Eigen values are neglected to further decrease the dimension of face space. This does not reduce the success rate much and is acceptable depending on the application of face recognition. Here only M' Eigenvectors with higher Eigen values are chosen for defining face space. The most critical task in this process is to choose value of M' (Maximum Eigen values chosen from Covariance Matrix) so that it does not result in high error rates for Face identification process. The M' must be selected such that error rates do not increase much and are acceptable depending on application for face recognition. V. KIT PROTOTYPE VI. CONCLUSION The Eigenface approach for face recognition process is fast and simple and works well under constrained environment. It gives speedy results which can be immediately deciphered by the Embedded prototype kit and the door operation can be controlled. For given set of images, due to high dimensionality of images, the space spanned is enormous. But as a matter of fact, all these images are directly related and actually span a lower dimensional storage. Using Eigen face approach reduces this dimensionality. The lower the dimensionality of the image space, the easier it is for face recognition. Any new face can be expressed as a linear combination of these eigen faces. This makes it easier to match any two faces and thus complete face recognition. We have developed a prototype of a door locking system where an electromagnetic relay is being used to represent the door locking system. This relay can be later connected to a solenoid driver to arrange a real time system. An Embedded PIC micro controller was used to collect the face recognition results from the MATLAB software through RS232 communication. An Embedded C program was developed and burned in the uC flash memory so that whenever the face recognition results are found to be successful, the uC will be able to drive the relay in order to open the door. After a certain delay, the relay is again brought back to open connection by the micro controller in order to close the door. ISSN: 2231-5381 http://www.ijettjournal.org Page 3853 International Journal of Engineering Trends and Technology (IJETT) – Volume 4 Issue 9- Sep 2013 VII. [1] REFERENCES Ahmad Yusairi Bani Hashim, Zamberi Jamaludin, “An Enduring Relationship between Biometric Traits and Security System”, International Journal of Research and Reviews in Information’s Security and Privacy (IJRRISP) Vol. I, No. 1, March 2011. [2] A.H. Maslow, The Farther Needs of Human Nature. New York: Penguin Group, 1971. [3] A.H. Maslow, Towards the Psychology of Being Second Edition New York: Van Nostrand Reinhold, 1968. [4] A.H. Maslow, Religion, Values and Peak Experiences, New York: Penguin Group, 1970. [5] Davies, Ellis, & Shepherd (EDS.), “Perceiving and Remembering Faces”, London: Academic Press, 1981. [6] T. Kohonen, “Self organization and associative memory”, Berlin: Springer-Verlag (1989). [7] T. Kohonen, P. Lehtio, “Storage and Processing of Information in Distributed Associative Memory Systems”, in G.E. Hinton & J.A. Anderson (Eds.), “Parallel Models of Associative Memory,” Hillsdale, New Jersey: Erlbaum, pp. 105-143. 1981. [8] Tae-Kyum Kim, Josef Kittler, Roberto Cipolla “Discriminative learning and Recognition of image set classes using Canonical correlation,” Published in IEEE Trans. On Pattern Analysis and Machine Intelligence, June 2007, pp 1005-1018 [9] S.T. Gandhe, K T Talele, A G Keskar, “Intelligent Face Recognition: A Comparative Study,” published in GVIP journal, Volume 7, Issue 2, August, 2007. [10] N Krishnan, GR Jothi, K Pulloor, GL Aaron, “Recognition of NonSymmetric faces using Principal Component Analysis,” ICVGIP Proceedings, October 2012. [11] M.A. Turk, A.P. Pentland, “Face Recognition using Eigenfaces,” Published in IEEE Computer Society Conference on Computer Vision and Pattern Recognition, 3-6 June 1991, pp 586-591. [12] Matthew Turk, Alex Pentland, “Eigenfaces for Recognition,” Vision and Modeling Group, The Media Laboratory, Massachusetts Institute of Technology, in J. of cognitive neuroscience, 1991, vol. 3, no. 1, pages 71 to 86. [13] A.M. Martinez and A.C. Kak, “PCA versus LDA,” IEEE Trans. Pattern Analysis and Machine Intelligence, vol. 23, no. 2, pp. 228–233, Feb. 2001 Nick Pears Thomas Heseltine and Jim Austin. “ Evaluation of image preprocessing techniques for eigenface based face recognition”. ACA Group, Dept. of Computer Science, University of York, 2002. ISSN: 2231-5381 http://www.ijettjournal.org VIII. AUTHOR DETAILS Srivalli P, Pursuing MTech (ECE) from Holy Mary Institute of Technology and science (HITS), Bogaram, Keesara, Hyderabad. Affiliated to JNTUH, Hyderabad, A.P, INDIA B Karunaiah, working as a Professor (ECE) at Holy Mary Institute of Technology and science (HITS), Bogaram, Keesara, Hyderabad. Affiliated to JNTUH, Hyderabad, A.P, INDIA K V Murali Mohan, working as a Professor and HOD (ECE) at Holy Mary Institute of Technology and science (HITS), Bogaram, Keesara, Hyderabad. Affiliated to JNTUH, Hyderabad, A.P, INDIA Page 3854