Iris Quality Standardization

Elham Tabassi

IBPC – April 3, 2014
Role of Standards

⟫ Open specifications for iris cameras, iris image properties 

(quality) and iris image record.

⟫ Prevent vendor lock-in. 

⟫ Allows for a marketplace of off-the-shelf product.

⟫ Allows modular integration of products without comprising 

architecture scope.

⟫ Allows for performance improvement (quality by design)

≫ Prevent GIGO

IBPC – April 3, 2014
Prevent GIGO 

IBPC – April 3, 2014
History

2002: IrisCode 

2007: ANSI/NIST ITL-1:2007 Type 17

2009: Initiation of ISO/IEC 29794-6 

2005: : Completion of ISO/IEC 19794-6 G1 (polar + rectilinear)

 (includes an `informative’ annex on image quality

2011: : ISO/IEC 19794-6 G2

ANSI/NIST ITLS-1:2011 Type 17

2008: Initiation of NIST IREX program

2013: SP 800-76 (PIV specification)

ISO/IEC 19794-2011: Polar format was removed 

because interoperability is sensitive to correct 

determination of the iris and pupil centers. 

IBPC – April 3, 2014
Subcommittee 37 “Biometrics” 

JTC 1 SC37 ISO/IEC 19794

≫ Biometric data interchange format

• Goal: interoperability 

• Avoid vendor lock-in

≫ Multipart standard

• Part 6: Iris image : Published 2011-

09-29

• Part 1: Framework

• Parts 2(finger minutiae), 4(finger 

image), 5(face image), etc.

JTC 1 SC37 ISO/IEC 29794

≫ Biometric sample quality

• Goal: interoperable performance

• Avoid vendor lock-in

• Avoid GIGO

≫ Multipart standard

• Part 6: Iris image: Expected 2014 

• Part 1: Framework

• Part 4(finger image) + Technical 

Report Part 5(face image).

IBPC – April 3, 2014
ISO/IEC 19794-6 

Biometric data interchange format – Part 6: Iris image

• specifies iris image 

interchange formats for 

biometric enrolment, 

verification and identification 

systems. 

• Image format

• Compression format for size 

constrained applications 

• Out of scope

• requirements on the optical 

specifications of cameras, photometric properties of iris 

images, enrolment processes, 

workflow and use of iris 

equipment. 

• AMD 1: Conformance Testing

IBPC – April 3, 2014
ISO/IEC 29794-6 

Biometric sample quality – Part 6: Iris image

≫ Defines and quantifies iris image 

quality components.

≫ for a single image,

≫ for two images being compared, and

≫ for acquisition device.

≫ Considers subject, environment and 

device covariates.

≫ For each quality component, it 

specifies

≫ description, computation method, 

units, and valid values/threshold.

IBPC – April 3, 2014
IQCE :: Quantitative support

⨱ The 2nd activity under 

⨱ Funded by DHS S+T

• Project “Radical improvement in iris quality 

assessment and maturing multimodal biometric 

utilization”

⨱ An evaluation based program for development of clear, 

implementable, and interoperable iris quality standard 

ISO/IEC 29694-6.

- To establish requirements on software or 

hardware capturing iris image

⨱ A refined list of image properties affecting iris 

recognition performance 

- To established requirements on iris image 

covariates

IBPC – April 3, 2014
IQCE 

Cropped

raw image QUALITY

VECTOR

1 Scalar quality

2 .. 17 Defined (standard) quality metrics

18..32 Reserved 

33..64 Vendor-defined quality metrics

 Q 

FNMR

9 IBPC – April 3, 2014
IQCE:: determining factors affecting 

iris recognition performance

Scalar 

quality

Usable 

iris area Iris-pupil 

contrast Iris-Sclera 

contrast 

Fraction of genuine comparisons rejected

False non

-match rate

IBPC – April 3, 2014
IQCE:: determining requirement 

(Ex. usable iris area)

Usable iris area - Enrollment image – IQAA C4x

Usable iris area – verification image – IQAA C4x

IBPC – April 3, 2014
Mutual quality :: How similarity of quality between 

two images being compared affects performance?

Verification :: scalar quality

enrolment :: scalar quality 

enrolment quality :: dilation

verification quality :: dilation

IBPC – April 3, 2014
Image quality components

Required 

1. Usable iris area [70,100]

2. Iris-sclera contrast [5,100]

3. Iris pupil contrast [30,100]

4. Pupil boundary circularity

5. Grey scale utilisation [6,20] 

6. Iris radius [80,253]

7. Pupil iris ratio [20,60]

8. Iris pupil concentricity [90,100]

9. Margin adequacy [80,100]

Recommended

10. Sharpness

11. Frontal gaze-elevation

12. Frontal gaze-azimuth

13. Motion blur

Mutual quality

≫ Illumination similarity

≫ Camera interoperability

≫ Common usable iris area

≫ Dilation constancy 

IBPC – April 3, 2014
Camera quality components 

≫ Dedicated illumination

≫ Modulation transfer function

≫ modulation of more than 50% 

at 1lp/mm using appropriate 

targets. 

≫ Optical distortion

≫ Pixel aspect ratio

≫ between 0.99 and 1.01. 

≫ Sensor signal-to-noise ratio

≫ larger or equal to 36 dB. 

≫ Spatial sampling rate 

≫ at least 15.7 pixel/mm.

IBPC – April 3, 2014
Status 

Time line

• Is balloted for Draft 

International Standard.

• Open issues: 

• Computation methods for 

sharpness, gaze angle

• Computation method for 

unified quality score 

Editorial Team

Editor: Elham Tabassi (NIST)

Co-editors: 

John Daugman (Cambridge 

University + Morpho), 

Raul Sanchez-Reillo (Universidad 

Carlos III de Madrid) 

Adam Czajka (Warsaw University 

of Technology and NASK)

IBPC – April 3, 2014
Thank You.

tabassi AT nist DOT gov

301 975 5292

http://www.nist.gov/itl/iad/ig/irexii.cfm

BCC – Tampa – Sept 17, 2013
IREX I

Accuracy of 

compact iris 

images in support 

of the ISO/IEC 

19794-6 and 

ANSI/NIST Type 17 

standards

IREX II / IQCE

Image quality 

definition, 

evaluation, 

calibration 

supporting the 

ISO/IEC 29794-6 

standard

IREX III

One-to-many

Iris recognition - 

Single and two-eye 

accuracy and 

resource 

requirements

IREX IV

Minimum error 

(weighted FNIR + 

FPIR) one-to-many 

recognition; Rapid 

ID compression 

profiles

IREX V

Instructional and 

guidance materials 

for image 

collection

IREX VI

Temporal 

dependence,

Iris aging, 

template aging, 

longitudinal 

effects.

IREX VII

Abstraction layers

Encapsulating core 

iris processing 

functions

IREX (Iris Exchange)

NIST’s umbrella program for iris recognition performance, standards, and image-based interoperability

2008-2009 2010-2011 2011-2012 2012 2012-2013 2012-2013 2013- 

Test Test Test Test Best Practice 

Documents Test Best Practice Documents

BCC – Tampa – Sept 17, 2013
Technical Approach 

Identify 

gaps/outreach 

(NWIP,AMD) 

Research/(lar

ge scale) 

evaluation 

Submit comment + 

Technical 

contribution

Advocate for 

NIST/USG 

position at 

M1 and SC37

Test performance and 

interoperability of the 

standard

Development of clear, 

robust, tested, and 

implementable content 

through extensive study 

and experiments, e.g. 

IREX I + IQCE 

aimed at 

strengthening the 

science behind the 

claims or preventing 

overly prescriptive 

requirements

e.g. MINEX 04 e.g. Liveness

e.g. IREX

Editorship of 8 intl. std

Host workshops 

tabassi@nist.gov :: NRC :: 22 March 2011