Master Thesis - Department of Computer Science
Master Thesis - Department of Computer Science
Master Thesis - Department of Computer Science
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A.6.3 Matching Score Computation<br />
Once the count <strong>of</strong> matched minutiae, NMM, is obtained, a matching score (represents<br />
the degree <strong>of</strong> match) is computed using one <strong>of</strong> the following formulas:<br />
MS =<br />
√<br />
NMM<br />
,<br />
P ∗ Q<br />
(A.38)<br />
MS = 2NMM<br />
. (A.39)<br />
P + Q<br />
where P and Q are the number <strong>of</strong> minutiae features in fingerprints P and Q, used for<br />
matching. We also used a normalized score, which takes into account the closeness<br />
(in the Euclidean sense) <strong>of</strong> paired minutiae features. This is computed as:<br />
NMS = MS<br />
D<br />
NMM +1<br />
. (A.40)<br />
where, D is the sum <strong>of</strong> all the Euclidean distances <strong>of</strong> the paired minutiae obtained<br />
after registration.<br />
A.7 Experimental Results<br />
The following databases are used for evaluating our fingerprint recognition system,<br />
• DBA consists <strong>of</strong> 10 subjects each having 8 samples (FVC 2002 Database [1]).<br />
• DBB consists <strong>of</strong> 10 subjects each having 8 samples (FVC 2004 Database [2]).<br />
Table A.1: Accuracy (in Percentage Accuracy) for DBA and DBB.<br />
Case DBA DBB<br />
Case A 88.75 69.00<br />
Case B 90.00 70.00<br />
The recognition performance for two databases are tabulated in Table A.1. The<br />
accuracies for each database is calculated for two different cases, where the matching<br />
score is calculated using : Case A Eqn. (A.40), and Case B Eqn. (A.38). Case<br />
A provides a stricter check than case B by taking Euclidean Distance (D) under<br />
consideration. In all cases, only one sample per subject is used for training and rest<br />
<strong>of</strong> the images are used for recognition.<br />
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