A comparison of subspace based face recognition methods

Download
2004
Gönder, Özkan
Different approaches to the face recognition are studied in this thesis. These approaches are PCA (Eigenface), Kernel Eigenface and Fisher LDA. Principal component analysis extracts the most important information contained in the face to construct a computational model that best describes the face. In Eigenface approach, variation between the face images are described by using a set of characteristic face images in order to find out the eigenvectors (Eigenfaces) of the covariance matrix of the distribution, spanned by a training set of face images. Then, every face image is represented by a linear combination of these eigenvectors. Recognition is implemented by projecting a new image into the face subspace spanned by the Eigenfaces and then classifying the face by comparing its position in face space with the positions of known individuals. In Kernel Eigenface method, non-linear mapping of input space is implemented before PCA in order to handle non-linearly embedded properties of images (i.e. background differences, illumination changes, and facial expressions etc.). In Fisher LDA, LDA is applied after PCA to increase the discrimination between classes. These methods are implemented on three databases that are: Yale face database, AT&T (formerly Olivetti Research Laboratory) face database, and METU Vision Lab face database. Experiment results are compared with respect to the effects of changes in illumination, pose and expression. Kernel Eigenface and Fisher LDA show slightly better performance with respect to Eigenfaces method under changes in illumination. Expression differences did not affect the performance of Eigenfaces method. From test results, it can be observed that Eigenfaces approach is an adequate method that can be used in face recognition systems due to its simplicity, speed and learning capability. By this way, it can easily be used in real time

Suggestions

Direct perception of traversibility affordance on range images through learning on a mobile robot
Uğur, Emre; Şahin, Erol; Department of Computer Engineering (2006)
In this thesis, we studied how physical affordances of the environment, such as traversibility for a mobile robot, can be learned. In particular, we studied how the physical properties of the environment, as acquired from range images obtained from a 3D laser scanner mounted on a mobile robot platform, can specify the traversibility affordance. A physics based simulation environment is used during exploration trials, where the traversibility affordances and the relevant features for each behavior are learne...
Recursive shortest spaning tree algorithms for image segmentation
Bayramoğlu, Neslihan Yalçın; Bazlamaçcı, Cüneyt Fehmi; Department of Electrical and Electronics Engineering (2005)
Image segmentation has an important role in image processing because it is a tool to obtain higher level object descriptions for further processing. In some applications such as large image databases or video image sequence segmentations, the speed of the segmentation algorithm may become a drawback of the application. This thesis work is a study to improve the run-time performance of a well-known segmentation algorithm, namely the Recursive Shortest Spanning Tree (RSST). Both the original and the fast RSST...
A Static analysis approach for service oriented software engineering (SOSE) designs
Çermikli, Can; Doğru, Ali Hikmet; Department of Computer Engineering (2010)
In this thesis, a static analysis approach is introduced in order to develop correct business processes according to the Web Service Business Process Execution Language (WS-BPEL) specification. The modeling of the business processes are conducted with Business Process Execution Language (BPEL) which is a popular orchestrator of Service Oriented Architectures (SOA) based system through the description of workflow. This approach is also integrated to the Service Oriented Software Engineering (SOSE) design tec...
Visual quality assessment for stereoscopic video sequences
Sarıkan, Selim Sefa; Akar, Gözde; Department of Electrical and Electronics Engineering (2011)
The aim of this study is to understand the effect of different depth levels on the overall 3D quality and develop an objective video quality metric for stereoscopic video sequences. Proposed method is designed to be used in video coding stages to improve overall 3D video quality. This study includes both objective and subjective evaluation. Test sequences with different coding schemes are used. Computer simulation results show that overall quality has a strong correlation with the quality of the background,...
A study on language modeling for Turkish large vocabulary continuous speech recognition
Bayer, Ali Orkan; Turhan Yöndem, Meltem; Department of Computer Engineering (2005)
This study focuses on large vocabulary Turkish continuous speech recognition. Continuous speech recognition for Turkish cannot be performed accurately because of the agglutinative nature of the language. The agglutinative nature decreases the performance of the classical language models that are used in the area. In this thesis firstly, acoustic models using different parameters are constructed and tested. Then, three types of n-gram language models are built. These involve class-based models, stem-based mo...
Citation Formats
Ö. Gönder, “A comparison of subspace based face recognition methods,” M.S. - Master of Science, Middle East Technical University, 2004.