MINEX II hase IV 

Request for comment on Test Design 

 atrick J Grother 

NIST, September 26, 2009 

Background 

1 MINEX II as produced two prior reports documenting t e accuracy and speed of t e matc -on-card implementations . T e 

algorit ms run on ISO/IEC 7816 conformant integrated circuit cards, and t ey matc ISO/IEC 19792-2 compact-format 

fingerprint minutiae fields. 

2

Audience 

T e document is circulated to parties interested in matc -on-card biometrics, and specifically to prospective participants in 

P ase IV of t e MINEX II test of on-card comparisons. Potential users of matc -on-card tec nologies may also be interested. 

 urpose 

T is document is circulated as a request for comments on new proposed tec nical aspects of t e MINEX II evaluation. T e 

existing evaluation is document in t e MINEX II API and CONOPS . 3

 roposed modifications in test execution and reporting 

Any party wis ing to provide opinions on t e entries in Table1 are invited to send t ese to patrick DOT grot er AT nist DOT gov 

# Area Specifics 

1. Template 

generators 

T e interoperability matrices in t e MINEX II reports ave been restricted to templates generated by 

t e following companies' implementations: 

Cogent A, Dermalog B, Bioscrypt C, Sagem Morp o D, Neurotec nologija E, Innovatrics F, NEC G, Cross Matc 

Tec nologies N, L1/Identix, Precise Biometrics 1D, XTec 1F, SecuGen 1G, BIO-key International 1J, Motorola 1L, 

Aware 1M, Sonda Tec nologies 1N, Neurotec nologija 1T, Aware 1Y, ImageWare 2A 

T ere as been a request to extend t is to use all of t ose listed ere: 

 ttp://fingerprint.nist.gov/minex/Results. tml 

Any views? 

2. DET 

reporting 

Prior MINEX II reports ave included DET c aracteristics for MOC implementations comparing minutia 

templates prepared using specific template generators. Dependencies on precisely w ic 

combination of generators as led to contention in w ic algorit m can claim to be t e "most 

accurate". 

NIST received a proposal to report a DET as follows. Use all K template generators used in t e MINEX 

evaluation (w ic do not report minutia quality values) and pool all comparison scores in t e DET 

computation. T us if t e previously reported DETs included N ~ 120,000 genuine comparisons and M 

~ 1,200,000 impostor comparisons, t e new DET would be based on KN and KM comparisons. 

4

1 T e reports document, respectively, P ases II and III, of t e MINEX II evaluation. T e reports are linked from 

 ttp://fingerprint.nist.gov/minexII 

2 W ile match- n-card is a trademarked term, it is used ere as a synonym for t e term n-card c mparis n. T e entire 

MINEX II evaluation considers standards-compliant cards and data records, and as t us far avoided proprietary data. 

3 See ttp://fingerprint.nist.gov/minexII/nistir_7485.pdf. 4 See ttp://fingerprint.nist.gov/minex 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

See Table 10 t e Marc 2006 MINEX 04 report, Perf rmance and Inter perability f the INCITS 378 Fingerprint Template 

NISTIR 7296. Linked from ttp://fingerprint.nist.gov/minex 

T is represents t e situation in w ic a MOC application is used in a federated application in w ic 

templates from K different organizations are used in equal number. T e purpose is to give a more 

robust, vendor neutral, statement of accuracy. 

T e range of accuracies [max/min/mean] could be displayed also. 

3. Zonal 

Quality 

Mask 

S ould t e record include t e regional quality mask described in Appendix A? 

Would accuracy improve? 

Would you provide a template generator t at computed zonal quality? 

Implementation: T e INCITS 378 standard does not include zonal quality masks. T e ISO/IEC 19794-2 

standard does. MINEX II would likely borrow t e ISO record structure for t e test and integrate wit 

INCITS 378. T e card DO is standardized already. 

4. T res old If t e test plan required you to state a t res old (in email to NIST) t at you believe, a priori, will -4 produce FMR less t an or equal to 10 would you be able to do so? 

5. Impostor 

distribution 

stability 

5 T e MINEX 04 test reported results for fixed t res old and s owed t at FMR as some dependency 

on t e producer of t e templates. Do you ave views on w et er impostor distribution stability 

s ould be included in MINEX II analyses? 

6. Cost model T e existing MINEX II protocol as ignored t e actual decision returned by a card executing a VERIFY 

command. Instead accuracy as been computed entirely from t e similarity scores required to be 

computed by t e card. 

T e proposal is to require participants to report similarity scores and decisions, wit t e objective of 

minimizing t e cost of ypot etical single finger financial services aut entication application. T e cost 

function would be 

C = P . CFNM . FNMR + (1-P) . CFM . FMR 

W ere 

P, t e prior probability of a genuine comparison, is set at 0.999 

CFNM, t e cost of a false non-matc , is set at 1, and 

CFM, t e cost of a false matc is set at 10000 

T is means t at an explicit matc / non-matc decision is required for eac trial. Explicit decisions are 

required because t e task of determining appropriate decision t res olds is a necessary part of any 

1:1 system. 

Comments on w et er to do t is, on t e functional form, and on t e values of t e costs and priors, 

are welcome. 

7. Properties 

of minutia 

detector 

Question to NIST: Are t ere some ot er rules w ic needs be met in order for a Ongoing MINEX 

approved extractor be considered for t e MINEX II? 

Answer: T e extractors in MINEX II differ from MINEX 04 / Ongoing MINEX in t at t ey s ould report 

minutia quality values. 

8. W ic 

extractor is 

t e default. 

Question to NIST: We are also a bit curious as to ow t e fallback extractor is c osen – t at is t e 

extractor used by matc ers submitted t at are not providing t eir own extractor. Will t is extractor 

be updated to t e next MINEX II round? 

Answer: 

T e question refers to t e minutia extractor used during t e aut entication attempt. 

In t e first public MINEX II report MX2D was used because it was t e only extractor submitted. In t e 

revision of t at report , t e MX2D (Sagem) was used, and occasionally supplemented wit MX2T 6

5 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

(Cogent). 

For t e upcoming P ase IV, t e appropriate uses of multiple extractors would be 

1. To pool t e templates as in row 2 above. 

2. To compare performance of t ose generators. 

Responses are welcome. 

Appendix A - Zonal Quality Specifications 

T e PC would make a INCITS 378 record t at augmented wit t e zonal quality structure s own in t is ISO/IEC 19794-2 

record. 

Field name and ISO/IEC 19794-2:2005 

clause numbers in parent eses 

Values Allowed Informative Remarks 

1. Format Identifier (7.3.1) 0x464D5200 i.e. ASCII "FMR\0" 

2. Version Number (7.3.2) 0x20323000 i.e. ASCII " 20\0". 

3. Record Lengt (7.3.3) 32 ≤ L ≤ 800 26 record eader + 4 view eader +2 extended 

data lengt + 6K. Max K is 128 

4. Capture Equipment Certifications (7.3.4) 0 

5. Capture Device Type ID (7.3.5) 0 

6. Size of Scanned Image in x direction (7.3.6) MIT In erited directly from input data 

7. Size of Scanned Image in y direction (7.3.7) MIT 

8. X ( orizontal) resolution (7.3.8) 197 

9. Y (vertical) resolution (7.3.9) 197 

10. Number of Finger Views (7.3.10) 1 

11. Reserved Byte (7.3.11) 0 

12. Finger Position (7.4.1.1) MIT In erited directly from input data 

13. View Number (7.4.1.2) 0 

14. Impression Type (7.4.1.3) 0 or 2 In erited directly from input data 

15. Finger Quality (7.4.1.4) MIT In erited directly from input data 

16. Number of Minutiae (7.4.1.5) 0 ≤ K ≤ 128 K minutiae data blocks 

17. Minutiae Type (7.4.2.1) 01b, 10b, or 00b 

18. Minutiae Position (7.4.2.2) MIT 

19. Minutiae Angle (7.4.2.3) MIT 

20. Minutiae Quality (7.4.2.4) 0, 1 ≤ Q ≤ 100 0 = unsupported 

21. Extended Data Block Lengt (7.5.1.1) ≥ 0 Eit er 0 for no extended data, or t e lengt of a 

zonal quality block 

22. Extended Data Area Type Code (7.5.1.2) 0x0003 Optional, only present if (7.5.1.1) is > 0. 

23. Zonal Q. Cell Widt and Heig t (7.5.4.1) 1 ≤ NPIX ≤ W Optional, only present if (7.5.1.1) is > 0. 

Zonal Q. Cell Widt and Heig t (7.5.4.1) 1 ≤ NPIX ≤ H Optional, only present if (7.5.1.1) is > 0. 

24. Zonal Q. Cell Quality Info. Dept (7.5.4.2) 1, 2, 4, 8 Optional, only present if (7.5.1.1) is > 0. 

T is value s all not be 0. 

25. Zonal Q. Cell Quality Data (7.5.4.3) Optional, only present if (7.5.1.1) is > 0. 

MIT = mandatory at time of instantiation 

T e information s own in blue would be sent to t e card as: 

6 See MINEX II Perf rmance f Fingerprint Match- n-Card Alg rithms P ase II / III Report NIST Interagency Report 7477 

(Revision I) linked at ttp://fingerprint.nist.gov/minexII/minex_report.pdf 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Table 1 – ISO/IEC 19794-2 minutiae template DO 

Tag L Value Comment 

‘7F2E’ L1 Biometric data template 

Tag L Value 

‘81’ L2 Finger minutiae data 

Field Size (bits) Valid Values 

X coordinate 8 [0,255] S 

Y coordinate 8 instances [0,255] 

Minutiae type 2 

Minutiae angle 6 [0,63] 

'94' L3 Zonal Quality Data 5+var See Table 2 0 or 1 

instances 

Table 2 – Zonal quality data 

FIeld Lengt 

(bytes) 

Values 

Allowed 

Informative Remarks 

1 Horizontal Resolution of t e Quality Map (8.4.1.1.2) 1 See Note 1 and Example 1 

2 Vertical Resolution of t e Quality Map (8.4.1.1.2) 1 

3 Quality Map Widt (8.4.1.1.3) 1 # cells in x orizontal direction 

4 Quality Map Heig t (8.4.1.1.3) 1 # cells in y vertical direction 

5 Cell Quality Information Dept (8.4.1.1.4) 1 1, 2, 4, 8 Not 0. 

6 Cell Quality Data (8.4.1.1.5) L Packed bits 

NOTE T e first draft Tec nical Corrigendum 1, SC37N2119 as one field for cell quality resolution, i.e. it assumes t e x-y resolutions 

are equal. However, t e ISO/IEC 19794-2:2005 record standard allows different cell resolutions in x and y. T erefore, if t e process of 

converting ISO/IEC 19794-2 record to compact-card templates is to become viable operationally, t en card zonal quality data needs to 

support anisotropic resolutions. 

EXAMPLE If t e orizontal cell dimension in a ISO/IEC 19794-2 zonal quality block (clause 7.5.4.1 of ISO/IEC 19794-2:2005) is 20 

pixels, and t e corresponding orizontal resolution is 197 pixels per centimeter (clause 7.3.8 of ISO/IEC 19794-2:2005), t en t e value of 

t e entry on line 1 of t is table (i.e. t e number of cells per decimeter) will be round(10 * 197 / 20) = 99, w ere t e rounding operator is 

now ere standardized.