Fingerprint Identification- FBI carries 198 million fingerprints on record

- Used for unique identification of a person

- First gained credibility when used to identify William West, who looked almost physically identical to a man named Will West (another inmate). The guards used fingerprints to successfully differentiate between the two prisoners.

Arch

Left Loop

Right Loop

Tented Arch

Whorl

The 5 Classifications

-To more closely identify a fingerprint, the ends of the swirls (minutiae) are mapped.

-The distances between minutiae are stored using a Euclidean algorithm or what the FBI uses (D9/7 wavelet based system)

Enhance the image

Calculate minutiae distances

Compare

Rotating image destroys accuracy!!

You might ask……..

What does this have to do with Data Structures ??

Arch

Left Loop

Right Loop

Tented Arch

Whorl

Hash( minutiae.value )

Hash( minutiae.value )

0

1

2

N-1

This allows for quick fingerprint identification

Some verification is required to check for error (recall fingerprints

being rotated)

References:• http://www.ccc.de/biometrie/fingerabdruck_kopieren.xml?language=en• http://cryptome.org/gummy.htm• http://www.optel.com.pl/article/english/article.htm• http://cryptome.org/fake-prints.htm• http://computer.howstuffworks.com/fingerprint-scanner6.htm• http://biometrics.cse.msu.edu/fingerprint.html• http://www.crimtrac.gov.au/fingerprintanalysis.htm• http://en.wikipedia.org/wiki/Fingerprint• http://www.nist.gov/srd/fing_img.htm• http://www.barcode.ro/tutorials/biometrics/fingerprint.html• http://www.fingerprints.tk/• http://www.fbi.gov/lawenforce.htm• http://engr.smu.edu/~rewini/• http://fingerprint.nist.gov/NFIS/• http://www.communitycenter.dsu.edu/biometrics/PROSECTION

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