| Refereed Publications
- Toru Wakahara, Yoshimasa Kimura, Akira Suzuki, Akio
Shio, and Mutsuo Sano, Fingerprint Verification
Using Ridge Direction Distribution and Minutiae Correspondence,
Systems and Computers in Japan, Vol. 38, No. 3, pp. 72-82,
Abstract - Fingerprint
verification technique is raising high expectations as
a means of personal identification based on physical features.
This paper proposes a fingerprint verification method
which can achieve minutiae matching with highly accurate
compensation for rotation and position deviation, as well
as high speed and stability. The process flow after binarization
of the gray-scale fingerprint image is as follows. (1)
Using the fingerprint ridge direction distribution in
each local region, highly accurate compensation for the
rotation and the position deviation between the enrolled
fingerprint and the input fingerprint is performed. (2)
The optimal correspondence between enrolled and input
minutiae is established by fast combinatorial search.
(3) By applying threshold processing to the distances
of the fingerprint ridge direction distributions and the
minutiae matching rate, the acceptance/rejection of the
person is decided. Fingerprint image data for 80 persons
X 4 fingers X 10 samples were collected using
a commercial electrostatic capacitance semiconductor fingerprint
sensor. The false rejection rate and the false acceptance
rate are investigated in fingerprint verification experiments,
and the effectiveness of the proposed method is demonstrated.
- Satoshi Otaka, Yoshihisa Nishiyama, Takahiro Hatano,
and Toru Wakahara, Fingerprint Verification Using
Perturbation Method, in Proceedings of MVA2007 IAPR
Conference on Machine Vision Applications, May 2007, pp.
Abstract - This paper
describes a new, powerful technique of fingerprint verification
based on a perturbation method. The proposed method consists
of four parts. The first part performs local FFT band-pass
filtering to enhance the cyclic ridge structure in respective
local areas. The second part is optimal block-wise shift
for preliminary matching. Then, the third part is application
of GAT correlation to realize affine-invariant shape matching.
Finally, the fourth part is detail matching by perturbation.
The key ideas of our perturbation method are in three
ways: extraction of core points from enrolled fingerprint
images, setting local windows around the core point, and
asynchronous perturbation of local windows for optimal
detail matching between input and each enrolled fingerprint
images. How to design the size of local windows, the range
and direction of perturbation, and the matching criteria
is crucial to the success of the proposed method. Experimental
results using the public FVC2000 fingerprint image database
demonstrate a sufficiently low equal error rate (EER)
of 5.55% for false rejection and false acceptance comparable
to those obtained by competing works.
- Minoru Yokobayashi and Toru Wakahara, A Study
on Optimal Binarization and Distortion-Tolerant Recognition
of Color Characters in Scene Images, IEICE Technical
Report, PRMU2007-110, pp. 105-110, October 2007.