Diapositive 1 - PowerPoint PPT Presentation

1 / 17
About This Presentation
Title:

Diapositive 1

Description:

Locating iris : often fails even on cooperative person ... Local feature extraction : Prelude. Daugman's System : Gabor's complex 2D Filters ... – PowerPoint PPT presentation

Number of Views:20
Avg rating:3.0/5.0
Slides: 18
Provided by: BiB8
Category:

less

Transcript and Presenter's Notes

Title: Diapositive 1


1
Person Identification technique using human iris
recognition
Christel-loïc TISSE1, Lionel Martin1, Lionel
TORRES2, Michel Robert2
1 Advanced System Technology STMicroelectronics 2
Université de Montpellier , Lirmm
Presented By BOLTZ Sylvain
2
Introduction Iris Biometrics
  • Iris great for authentification probability of
    two same iris pattern is almost 0 , iris
    protected from environment , aging
  • Locating iris often fails even on cooperative
    person
  • Local features extraction Daugmans system not
    fully publicated in litterature, new approach on
    recent 2D-Hilbert transform works.

3
Locating Iris Daugmans System
  • Use of a circular edge detector
  • Daugmans Localization Sytem appears to succeed
    only with 86 ratio.

Intro-Differential Operator
The main fail cause is Spot reflection in the
pupil.
4
Locating Iris Circular Hough Transform
  • Detection strategy combination of the
    integro-differential operator and a Hough
    transform
  • First Hough transform to locate the center then
    integro-differential operators
  • Circular Hough transform

5
Cartesian to polar reference transform
  • We unfold the circular picture into a
    dimensionless rectangular image
  • Pupil not perfectly circular
  • Iris outer boundary can be faked by contact lens.

6
Local feature extraction Prelude
  • Daugmans System Gabors complex 2D Filters
  • Iris code emergent frequency, instantaneous
    phase.
  • Problem They are not defined for a real signal
  • Solution Analytic Image. (fast algorithm)
  • Where H is Hilbert Transform

7
Local feature extraction
Rectangular Iris Image NxM
Real valued Signal The iris image.
8
Local feature extraction
Rectangular Iris Image NxM
2D Pass-Band Filter
  • 2D Pass-Band filter must not dephase the signal.
  • We use a 2D Hamming window
  • X(u,v)X1(u)X2(v)
  • Where X1(u) and X2(v) are Well-Known
  • 1D Hamming window.

9
Local feature extraction
Rectangular Iris Image NxM
2D Pass-Band Filter
  • We build the analytic image of the output Signal

10
Local feature extraction
Emergent Frequency
Rectangular Iris Image NxM
2D Pass-Band Filter
11
Local feature extraction
Rectangular Iris Image NxM
2D Pass-Band Filter
12
Local feature extraction
Rectangular Iris Image NxM
2D Pass-Band Filter
Same on 3 different Hamming Filters
13
Local feature extraction
Rectangular Iris Image NxM
2D Pass-Band Filter
Iris Code
Final Output Binary Images NxM by
Thresholding. Is the IRIS CODE. Then a simple
Hamming distance test between the template and
the extracted code.
14
Experimental results
15
Experimental results
  • Iris Localisation
  • On a 300 images various iris database (contact
    lens , glasses, )
  • Without Hough transform preprocessing 86
  • With Hough transform preprocessing 100
  • Complexity

16
Experimental results
  • False Acceptance Rate and False Reject Rate
  • this estimation of FAR and FFR is without
    enrolment
  • FAR0 gt FRRlt3( 8 bad localization)

17
Conclusion, Possible Improvments and Critics.
  • Same Performance as Daugmans System in local
    feature extraction
  • Great amelioration on Locating iris with Circular
    Hough Transform.
  • Too small test database
  • In progress
  • memory cost
Write a Comment
User Comments (0)
About PowerShow.com