Overview
ISO/IEC TR 24722:2015 - Information technology - Biometrics - Multimodal and other multibiometric fusion is a Technical Report that describes and analyses current practices for combining multiple biometric sources. It provides high‑level explanations of multibiometric concepts and fusion approaches (for example multi‑characteristic‑type, multiinstance, multisensorial, multialgorithmic, multipresentation) without prescribing a single implementation. This guidance helps developers, integrators and standards authors understand tradeoffs in combining biometric samples, features, scores and decisions.
Key topics
- Scope and purpose
- Explains types of multibiometric systems and why fusion improves performance (accuracy, security, and reduced failure‑to‑enrol).
- Clarifies that this is a Technical Report (guidance), not a normative standard.
- Multibiometric categories
- Definitions for multi‑characteristic‑type, multiinstance, multisensorial, multialgorithmic, and multipresentation systems.
- Presentation modes
- Simultaneous vs sequential presentation of biometric samples and their impact on system design and user flow.
- Levels of fusion
- Decision‑level fusion (combining accept/reject outputs), including simple and advanced logic.
- Score‑level fusion, including score normalization and score combination methods (requires attention to genuine/impostor distributions).
- Feature‑level and image/sample fusion approaches.
- System architectures
- Concepts such as cascaded and layered systems that use thresholds and intermediate decisions to drive additional capture or processing.
- Characterisation data
- Use of data to support normalization and fusion decisions, and considerations for correlated sources.
- Practical considerations
- Correlation between sources, implementation maturity, and limitations of fusion methods given application‑dependent data.
Applications and who uses it
ISO/IEC TR 24722:2015 is targeted at:
- Biometric system architects and integrators designing multimodal authentication or identification systems.
- Vendor R&D teams developing multialgorithmic or multisensor biometric products (including AFIS implementations).
- Government agencies and system procurers evaluating biometric fusion strategies for identity, border control, and secure access.
- Researchers and standards developers seeking consistent terminology and high‑level guidance on fusion tradeoffs.
Practical benefits include improved false accept/reject tradeoffs, reduced failure‑to‑enrol (FTE) rates, greater resilience to sensor or algorithm failure, and more flexible security/usability configurations.
Related standards
- ISO/IEC 2382‑37 (biometrics terminology) - referenced for definitions and alignment.
- Work produced by ISO/IEC JTC 1/SC 37 (Biometrics) - TR 24722 provides a reference for other biometric standards and implementers.
Keywords: ISO/IEC TR 24722:2015, multimodal biometrics, multibiometric fusion, score‑level fusion, decision‑level fusion, feature‑level fusion, multialgorithmic, multisensorial, biometric systems.