April, 2003IKTA-88/2001 Institute of Graphology, Hexium, BMF NIK Development of an Autonomous, Reliable, High Quality Signature Verification Device Institute.

April, 2003IKTA-88/2001 Institute of Graphology, Hexium, BMF NIK

Development of an Autonomous,

Reliable, High Quality Signature Verification Device

• Institute of Graphology, Ltd.

• Hexium Ltd.

• Budapest Polytechnic, John von Neumann Faculty of Informatics

April, 2003IKTA-88/2001 Institute of Graphology, Hexium, BMF NIK

Table of contents

• Project goals

• Participants

• Preliminary results

April, 2003IKTA-88/2001 Institute of Graphology, Hexium, BMF NIK

Signature verification – project goals

• Develop a device prototype device:

• Capable of verifying signatures of individuals

• High precision, reliable

• Compact, autonomous device

• Can be used to verify both static (“off-line

verification”) and dynamic (on-line) signatures

April, 2003IKTA-88/2001 Institute of Graphology, Hexium, BMF NIK

Applications

• Money transfer

• Other bank operations

• Bank card purchases, check redemption

• Criminalistic applications

• Governmental applications

• Record office

• Verifying signatures on contracts

• Jurisdiction processes

• Supporting the work of graphology experts

April, 2003IKTA-88/2001 Institute of Graphology, Hexium, BMF NIK

Members of the consortium

• Institute of Graphology, Ltd.

(Dr. Tamás Agárdi)

• Hexium Ltd.

(Dr. Tamás Nagy)

• Budapest Polytechnic John von Neumann Faculty of

Informatics

(Dr. László Kutor)

April, 2003IKTA-88/2001 Institute of Graphology, Hexium, BMF NIK

Institute of Graphology, Ltd.

• Activities: research, education, consulting

• Topics: character analysis, vocational guidance, lie detection by graphological means, handwriting analysis, identification

• Contact information:1126 Budapest, Böszörményi út 20-22. Telephone: +36 1 201-5568Tel/Fax: +36 1 201-5569, 355-8193E-mail: [email protected]: www.grafint.hu

April, 2003IKTA-88/2001 Institute of Graphology, Hexium, BMF NIK

Hexium Ltd.

• Activities: research, development, production (hardware, software)

• Topics: security, image processing, industrial measurement and process control

• Contact information:1134 Budapest, Váci út 51/bTelephone: +36 1 320-8338Telefax: +36 1 340-8072E-mail: [email protected]

[email protected]: www.hexium.hu

April, 2003IKTA-88/2001 Institute of Graphology, Hexium, BMF NIK

• Activities: Informatics education, research, development • Topics: Signal processing, biometrics, classification

• Contact information: 1034 Budapest

Nagyszombat u. 19. Telephone: +36 1 3684 610 Telefax: +36 1 3689 632 E-mai: [email protected] WWW: www.nik.bmf.hu

Budapest Polytechnic John von Neumann Faculty of Informatics

April, 2003IKTA-88/2001 Institute of Graphology, Hexium, BMF NIK

Project Phases• Phase 1: -March, 2002

Preparation, specifications• Phase 2: -January 2003

Corpus and algorithm development• Phase 3: -March 30, 2003

Hardware, demo• Phase 4: -June 30, 2003

Demo test, documentation

April, 2003IKTA-88/2001 Institute of Graphology, Hexium, BMF NIK

Preliminary Results

• Results on dynamic (digitized) signatures

• Reliable digital signature acquisition

• Signature analyzing algorithms

• Signature database

April, 2003IKTA-88/2001 Institute of Graphology, Hexium, BMF NIK

Calibrated dynamic signature measurement

Linearity Pressure Pen angle

April, 2003IKTA-88/2001 Institute of Graphology, Hexium, BMF NIK

Calculated dynamic signature features

Measured features: - XY coordinates- pressure - pen angle

Calculated features: - signature length data - duration data- time functions

Velocity-, pressure-, pen angle functions

t t t

v p d

April, 2003IKTA-88/2001 Institute of Graphology, Hexium, BMF NIK

Personal data Biometric profile

Signature database structures

Development database Decision database

Code Static sign. Dynamic sign. Calculated static feaures Calculated dynamic features

April, 2003IKTA-88/2001 Institute of Graphology, Hexium, BMF NIK

Preliminary Results

• Results on static (scanned) signatures

• Corpus

• Algorithms

April, 2003IKTA-88/2001 Institute of Graphology, Hexium, BMF NIK

Corpus design, corpus propertiesGoal: Representativeness!

• 2000 individuals• 15 min/person• 6 signatures for registration• 19 original (varying pen, size of region,..)

• 6 forgeries/individual • (skilled, simple, random)

• Balanced experiment design (many factors)

Altogether:

40,000 signatures15,000 pages

200 GB of disk space (compressed)

April, 2003IKTA-88/2001 Institute of Graphology, Hexium, BMF NIK

Automatic processing

• Processing of forms

• Processing empty A4sheets

Example

April, 2003IKTA-88/2001 Institute of Graphology, Hexium, BMF NIK

Manual Cleaning

Clean, large, high quality corpus

April, 2003IKTA-88/2001 Institute of Graphology, Hexium, BMF NIK

Development of the Signature Verification Algorithms

• Generic scheme:

April, 2003IKTA-88/2001 Institute of Graphology, Hexium, BMF NIK

Challenges

• The system must learn with a very limited set of samples (6!)..

• .. while rejecting forgeries

• Solution:• Learn a good prior of

signatures

April, 2003IKTA-88/2001 Institute of Graphology, Hexium, BMF NIK

Results

• False rejection rate: 5%

• False acceptance rate (simple forgeries): 0.27%

• False acceptance rate (skilled forgeries): 18.99%

• Verification time: <0.5second/signature on a PIII 1GHz

• Memory requirements: <2MB (50KB/signature)

April, 2003IKTA-88/2001 Institute of Graphology, Hexium, BMF NIK

Detection-error tradeoff curves

Simple forgeries

Skilled forgeries

April, 2003IKTA-88/2001 Institute of Graphology, Hexium, BMF NIK

Comparisions

Method FRR FAR-simple

FAR-skilled

Sansone&Vento [1] (one of the best published results)

2.04% 4.29% 19.8%

Trained human subjects (recent measurement)

23% n.a. 24% (actually on skilled+simple)

Our method; version A

5% 0.27% 18.9%

Our method; version B

23% 0% 4.5%[1] Sansone & Vento: “Signature Verification: IncreasingPerformance by a Multi-Stage System”, Pattern Analysis & Applications (2000)3:169–181

April, 2003IKTA-88/2001 Institute of Graphology, Hexium, BMF NIK

1126 Budapest, Böszörményi út 20-22. Telephone: +36 1 201-5568Tel/Fax: +36 1 201-5569, 355-8193E-mail: [email protected] Edit Tóth, project leaderWWW: www.grafint.hu

Contact Information