Performance Evaluation

For each database and for each algorithm:

• Each sample in the subset A is matched against the remaining samples of the same finger to compute the False Non Match Rate FNMR (also referred to as False Rejection Rate - FRR). If the matching g against h is performed, the symmetric one (i.e., h against g) is not executed to avoid correlation. The total number of genuine tests (in case no enrollment rejections occur) is:
  ((8*7) /2) * 100 = 2,800

• The first sample of each finger in the subset A is matched against the first sample of the remaining fingers in A to compute the False Match Rate FMR (also referred to as False Acceptance Rate - FAR). If the matching g against h is performed, the symmetric one (i.e., h against g) is not executed to avoid correlation. The total number of false acceptance tests (in case no enrollment rejections occur) is:
  ((100*99) /2) = 4,950

Although it is possible to reject images in enrollment, this is strongly discouraged. In fact in FVC2004, as in FVC2002, rejection in enrollment is fused with other error rates for the final ranking; in particular, each rejection in enrollment will produce a "ghost" template which will not match (matching score 0) with all the remaining fingerprints.

For each algorithm and for each database, the following performance indicators are reported:

• REJ_ENROLL (Number of rejected fingerprints during enrollment)
• REJ_NGRA (Number of rejected fingerprints during genuine matches)
• REJ_NIRA (Number of rejected fingerprints during impostor matches)
• Impostors and Genuines distributions
• FMR(t)/FNMR(t) curves, where t is the acceptance threshold
• ROC(t) curve
• EER (equal-error-rate)
• EER^* (the value that EER would take if the matching failures were excluded from the computation of FMR and FNMR)
• FMR100 (the lowest FNMR for FMR<=1%)
• FMR1000 (the lowest FNMR for FMR<=0.1%)
• ZeroFMR (the lowest FNMR for FMR=0%)
• ZeroFNMR (the lowest FMR for FNMR=0%)
• Average enrollment time
• Average matching time
• Average and maximum template size
• Maximum amount of memory allocated

The following average performance indicators are reported over the four databases:

• Average EER
• Average FMR100
• Average FMR1000
• Average ZeroFMR
• Average REJ_ENROLL (Average number of rejected fingerprints during enrollment)
• Average REJ_MATCH (Average number of rejected fingerprints during genuine and impostor matches)
• Average enrollment time
• Average matching time
• Average template size (Calculated on the average template size for each database)
• Average memory allocated (Calculated on the maximum amount of memory allocated for each database)