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FEATURE

Biometric Technology Today January 2009

Facing the future with 3D facial recognition technology

A photograph – the basic requirement for facial recognition – is stored in all European pass-ports. Around 60 countries worldwide are now issuing electronic travel documents based on ICAO specifications, making the ePassport an unprecedented success model. Some countries report that already about 25% of the docu-ments submitted at their border controls are ePassports.

Image qualityCitizens have become familiar with the strict demands made on the quality of photographs used for 2D facial recognition from their applications for documents. This applies in particular to pictures of the face taken from the front. It is essential for 2D facial recogni-tion that image material is of good quality. A comprehensive set of criteria for assessing image quality has been developed in order to ensure this.

The factors that influence image quality are many and varied and it is difficult to ensure

compliance with these criteria, both when taking the pictures and when subsequently comparing them. For example, it is not unu-sual for citizens to take their own passport photographs. Even if these images meet all the quality criteria, the ensuing procedure evi-dently leads to a lot of variation. Furthermore, there is a risk that the photographs may have been manipulated using freely available image-processing software. Such images might pass quality control unhindered but they cannot be used for biometric comparison.

Another drawback to 2D procedures is the lack of liveness detection, making its use in non-supervised and automated environments challenging. In contrast, 3D facial recognition offers fundamentally better ways of recognis-ing facial images as it is more independent of pose variation. Also, the size of a facial image is never prejudiced in 3D recognition. Unlike 2D photographs, where the unspecified dis-tance between the individual and the camera can lead to differently sized images, 3D photo-graphs are metrically correct.

Advantages of 3D technologyA border control scenario in which each border control official is monitoring several automatic border-control lanes would pose an additional challenge to maintaining security standards. 3D technology offers great potential for use in this scenario since the implementation of 3D tech-nology would advance the automation of the processes involved. The ICAO, which is continu-ously enhancing standards for travel documents, is also thinking in this direction. In a Request for Information (RFI) issued in October 2007, for example, the New Technology Working Group asked companies to submit technological devel-opments that might make automated border controls possible in the future.

3D FaceThe ‘3D Face’ project team has been work-ing on answers to this challenge for some time now, and is due to conclude in March 2009. The project’s core consortial team consists of Bundesdruckerei, Sagem Sécurité and Berlin Airport, along with 13 other partners. The main aim of the project is to improve the effi-ciency of procedures to the extent that they can be used operationally for border controls or to enforce access restrictions to secure environ-ments, e.g. at airports. Within the project team, Bundesdruckerei is responsible for the elec-tronic personalisation of the data on the chip, document visualisation and verification, and for system integration of this component.

How does this work on a technical level? A facial data acquisition device was developed within the scope of the project, as were algo-rithms by the various partners. This device works with structured light and supports a scanning period of just a quarter of a second. The efficiency of the components is currently being evaluated under operating conditions, which require fast processing and concurrent operation. For this purpose, the components developed in the project have been assembled in a prototype installation offering acquisition and verification modules. In the acquisition mod-ule, the 3D biometric facial data are stored on a smart card. During verification, these data are read from the smart card and compared with the image that is made live.

Member states of the European Union have been issuing ePassports with biometric features for some time now. These features can be used to trigger and to automate sovereign verification and identification processes at border con-trol stations. Bundesdruckerei’s Björn Brecht believes 3D facial recognition will improve the efficiency of these processes by offering considerable advantages over traditional 2D recognition currently used. 3D facial recognition prototypes are being developed and their practical usefulness is being tested as part of the EU-Commission-funded research project ‘3D Face’.

Figure: Example of 3D facial recognition

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9January 2009 Biometric Technology Today

One of the highlights of the year was a US$1 billion FBI contract won by Lockheed Martin, to develop and maintain its Next Generation Identification (NGI) multi-modal biometrics system for use by state, local and federal authorities in the US. The system will expand the FBI’s fingerprint capacity, dou-bling the size of its previous database. It will also include palm prints, iris and facial recog-nition capabilities, and be able to accommo-date other biometric forms that may mature and become important to law enforcement efforts in the future.

The project relies on components developed by Bundesdruckerei for electrical person-alisation and for reading the smart card. The ‘Persotec’ software is a flexible solution for the electrical personalisation of chips in machine readable travel documents. The personal data of an individual and his or her biometric features are stored in the document in accordance with the latest ICAO specifications. The ‘Visotec’ verifier is used as the reading device, comple-mented by ‘Visocore Inspect’ as the evaluation software application for the automatic verifica-tion of travel documents. This allows for almost 100% of machine readable travel documents to be automatically checked and thus offers high-quality support in assessing the authenticity of documents.

TestingA set of features that is device-independent would currently still take up too much space to be stored on a smart card and therefore tem-plates are stored on the chip. Since the latter only require a small amount of storage space, different algorithms developed in the course of the project can be evaluated in parallel in the pilot application. The biometric reference data stored on the chip are protected from unau-thorised reading by the Basic Access Control (BAC) method known from first-generation ePassports. BAC requires the optical evaluation of the machine-readable zone before the reading device is granted access to the data stored on the chip.

The live test was carried out in cooperation with Berlin’s Schönefeld Airport. The system was installed there at a busy checkpoint

adjacent to the airfield which is open 24 hours a day, seven days a week. About 130 volunteer staff members were photographed by the 3D system for the test; smart cards with biometric reference data were then cre-ated and issued. During the three-month trial, the participants were asked to carry out biometric verification every time they passed the checkpoint. The aim was to reach as many successful verifications as possible – at least 10 000 – in order to create a conclu-sive data pool. Another 10 000 verifications are planned in another trial taking place at Salzburg airport. This project will run until the end of January 2009, and is a similar set-up to the pilot held at Schönefeld.

Although the evaluations are far from com-plete, the verification results of the test have been very promising so far. These and all the project’s other findings – particularly feature definition and data formats – will be forwarded directly to the international standardization bod-ies. Although 3D facial recognition is still in its infancy, the advantages will very likely encourage the use of facial recognition in unattended and automated environments in the future.

This feature was provided by Björn Brecht, technical account support, key account management, German Security Authorities & Public Affairs, Bundesdruckerei. He can be contacted at Tel: +49 30 2598 2204, mobile: +49 172 3227943, email: bjoern.brecht@bdr.de, Web: www.bundesdruckerei.de

3D Face project partners are:• Bundesdruckerei, Germany (electronic personalisation of the data on the chip, document

visualisation and verification, and system integration of individual components;• Sagem Défense Sécurité, France (consortium manager and project coordinator);• Fraunhofer Institute for Computer Graphics Research IGD, Germany (sub-project

management research, testing of the performance and security of the system, privacy protection, algorithm development);

• Philips Research, Netherlands (privacy protection);• Cognitec Systems, Germany (face recognition);• Viisage Technology, Germany (face recognition);• Polygon Technology GmbH, Germany (3D scanner);• Computer Graphics Center, Germany (3D data acquisition and algorithm development);• University of Kent, UK (multimodal facial features and fusion);• University Twente, Netherlands (3D data acquisition and algorithm development);• Institute of Bio-structure and Bio-images of the National Research Council of Italy (CNR,

Standardisation, cross-jurisdictional and societal aspects);• Flughafen Berlin Schönefeld, Germany (demand analysis, validation and demonstration).

Biometrics review: 2008/2009In a year that saw the credit crunch dominate the international business agenda, the biometrics industry appeared to be remarkably resilient. Government-based schemes that had been in the planning stages for some time finally went live, and even the private sector showed it still had an appetite for the technology. But there are tough times ahead. Some planned schemes are likely to be put on hold, while others may take longer than anticipated to be rolled out. However, with both govern-ment and enterprise keener than ever to combat wastage, schemes that can boost efficiency will still be in demand over the challenging months ahead. As 2009 begins, we look back at some of the issues that shaped the agenda during 2008, and examine the prospects for the industry over the next 12 months.

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