August 2015
Intermediate to advanced
242 pages
7h 33m
English
Content preview from Touchless Fingerprint Biometrics
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Touchless Fingerprint Recognition
93
where u and v are the x and y spatial frequencies, respectively, in the frequency
domain, r
q
is a parameter empirically tuned according to the mean ridge frequency
of the used dataset, and α
q
is the spatial frequency of the frequency filter.
Then, the final estimation of the frame quality is given by analyzing the
enhanced image E using the software NIST NFIQ (described in Section 4.5), as
follows:
Q
NFIQ
= NIST NFIQ(E(x, y)). (5.11)
The filters described in Equation 5.9 and Equation 5.10 obtain images repre-
senting only the spatial wavelengths of the ridge pattern, which are compatible with
the approaches designed to estimate the quality of touch-based fingerprint samples.
We selected the software NIST NFIQ because it ...