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Master Thesis - Department of Computer Science

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combine the discriminative informations obtained from null space and range space<br />

for constructing a dual space. Then forward or backward selection technique is used<br />

to select optimal feature set from dual space. On the other hand, decision fusion<br />

based method constructs two different classifiers on the null space and range space<br />

separately and then combines them using decision fusion strategies. Results <strong>of</strong> all the<br />

three methods have been shown over three standard databases.<br />

There are severe drawbacks and risks <strong>of</strong> using a unifeature biometric recognition<br />

system, specifically recognition based on fingerprint or face alone. A machine which<br />

has the ability to only analyze data, but has no power to determine if the data has<br />

been fed into by an authorized person or not, is vulnerable to such acts <strong>of</strong> impostors<br />

who are always on the lookout to create innovative means <strong>of</strong> breaking into a system.<br />

Multimodal biometry which uses multiple sources <strong>of</strong> information for decision-making<br />

is a first choice solution for the above defined problem.<br />

In this thesis, a new approach for combining evidences from face and fingerprint<br />

classifiers at the decision level has been proposed. In this approach, each <strong>of</strong> the face<br />

and fingerprint classifier is separately exploited on the basis <strong>of</strong> availability <strong>of</strong> class-<br />

specific information to enhance combination performance. Results using face and<br />

fingerprint databases, show that the proposed methodology <strong>of</strong> using class-specific<br />

information at classifier’s response outperforms the state-<strong>of</strong>-art fusion techniques.<br />

Keywords: Face, dual space, subband face, decision fusion, feature fusion,<br />

eigenspace, multimodal, biometry.<br />

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