a cross-sensor evaluation of three commercial iris cameras for iris biometrics ryan connaughton and...
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A Cross-Sensor Evaluation of Three Commercial Iris Cameras for Iris
Biometrics
Ryan Connaughtonand
Amanda Sgroi
June 20, 2011CVPR Biometrics Workshop
Computer Vision Research LabDepartment of Computer Science & Engineering
University of Notre Dame
Objectives
Compare three commercially available sensors
– Does one sensor consistently out-perform the others?
– What factors impact sensor performance the most?
Observe performance of sensors in a cross-sensor scenario
– What kind of performance can we expect from a cross-sensor system?
– What is the relationship between single-sensor and cross-sensor performance? 2
Overview of Experiment Strategy
Collect images for the same subjects using all 3 sensors under similar conditions
Use 3 different matching algorithms to perform matching experiments
• In a single-sensor context
• In a cross-sensor context
Analyze performance of sensors in each scenario
3
Sensors
4
Sensor
Iris-to-Sensor Distance
Wavelength(s) of NIR Illumination
Type of Illumination (cross or direct)
Acquisition Instructions
S1 8 to 12 inches 820 nm Both (same time) Sensor Prompt
S2 10 to 14 inches
770 and 870 nm Both (different times)
Sensor Prompt
S3 13 inches 870 and 760 nm Cross * Operator
*Speculation
Image Examples
5
S1 S2 S3
Same Subject, Same Session Images
Data Collection Results
23,444 Iris Images acquired, spanning 510 subjects (1,020 unique irises)
6
The Matching Algorithms
A1
- Similarity Score
- Asymmetric Scores
A2
- Distance Score
- Asymmetric Scores
A3
- Distance Score
- Symmetric Scores
7
8
Segmentation Information
9
Segmentation Information
Note: Image information using A1 is not easily accessible and is thus not included.
Match and Non-Match Comparisons
10
The Experiments
S1 vs S1
S2 vs S2
S3 vs S3
S1 vs S2
S1 vs S3
S2 vs S3
11
Single-Sensor &
Cross-Session
Cross-Sensor &
Cross-Session
These experiments were repeated for all 3 matchers
12
ROC Curves Using A1
13
ROC Curves Using A2
14
ROC Curves Using A3
15
TAR's at FAR = 0.01
A1 A2 A3
S1 vs S1 0.9997 (1) 0.9898 (2) 0.9949 (1)
S2 vs S2 0.9993 (3) 0.9937 (1) 0.9857 (4)
S3 vs S3 0.9978 (6) 0.9819 (6) 0.9818 (5)
S1 vs S2 0.9995 (2) 0.9890 (3) 0.9858 (3)
S1 vs S3 0.9986 (4) 0.9848 (5) 0.9870 (2)
S2 vs S3 0.9984 (5) 0.9856 (4) 0.9807 (6)
Numbers in parentheses indicate ranking within the corresponding matching algorithm
16
Sensor Rankings @ FAR = 0.01
A1 A2 A3
1 S1 vs S1 S2 vs S2 S1 vs S1
2 S1 vs S2 S1 vs S1 S1 vs S3
3 S2 vs S2 S1 vs S2 S1 vs S2
4 S1 vs S3 S2 vs S3 S2 vs S2
5 S2 vs S3 S1 vs S3 S3 vs S3
6 S3 vs S3 S3 vs S3 S2 vs S3
Brackets indicate that performance difference at FAR=0.01 may not be statistically significant
17
Single-Sensor Conclusions
S3 consistently performed the worst for all matchers
S1 was best for 2 of 3 matchers
Best overall performance was achieved using S1 sensor with A1 matcher (TAR=0.9997 @ FAR=0.01)
18
Cross-Sensor Conclusions
A1: Cross-sensor performance was between performance of individual sensors
A2: In general, cross-sensor performance was between performance of individual sensors
– S1 vs S2 actually performed slightly worse than either single sensor
A3: Individual sensor performance is not a good predictor of cross-sensor performance
– S1 vs S3 appears to perform better than S1 vs S2
19
General Conclusions
Sensors and matching algorithms should be evaluated in combination, not separately
In some cases, adding a new and “better” sensor for cross-sensor matching will increase performance, but in some cases it will degrade performance
Single-sensor performance is not always a reliable predictor of cross-sensor performance
20
Future Work
Which results are statistically significant?
What factors have the largest effect on performance?
– Pixels on the iris
– Dilation ratio
– Occlusion
– Contact Lenses
– Order of sensors during acquisition
– Focus or other quality metrics
– Illumination
21
Thanks!
Questions?
Acknowledgments: This work is sponsored under IARPA BAA 09-02 through the Army Research Laboratory and was accomplished under Cooperative Agreement Number W911NF-10-2-0067. The views and conclusions contained in this document are those of the authors and should not be interpreted as representing official policies, either expressed or implied, of IARPA, the Army Research Laboratory, or the U.S. Government. The U.S. Government is authorized to reproduce and distribute reprints for Government purposes notwithstanding any copyright notation herein.
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