09/15 Notes

Level 1 Fingerprints

Class

1. Arch / Tented Arch
2. Whorl
3. Left Loop
4. Right Loop
5. Double Loop

My fingerprints look like

Right

• Thumb: Double Loop
• Pointer: Whorl
• Middle: Arch
• Ring: Whorl
• Pinkie: Arch

Left

• Thumb: Arch
• Pointer: Whorl
• Middle: Arch
• Ring: Whorl
• Pinkie: Whorl

Verification System

Give it a threshold to reach

EX: System has 3 samples, person gives 3 samples

• 6 choose 2 = number of scores

Scores

Either Genuine score or Imposter score

Genuine Score compare samples from same identity

Imposter Score compare samples across identities

Genuine + Imposter = Total Number of Scores

From Example:

• you can have 6 genuine and 9 imposter
• You could have 12 genuine and 18 imposter

This depends on the matcher

• Symmetric Matcher: A to B = B to A
• Asymmetric Matcher: A to B may or may not be equal to B to A

Matchers

EX:

Symmetric Matcher

1. N identities
2. m samples per identity

• Number of Scores = NM choose 2
• Number of Genuine = N x M choose 2
• Number of Imposter = Number of Scores - Number of Genuine = N choose 2 x m^2

False Match Rate = fmr(eata) = number of imp > eata / number of imp False NonMatch Rate = fnmr(eata) = number of genuine < eata / number of genuine