ANSI INCITS 378:2019 pdf free download – for Information Technology – Finger Minutiae Format for Data Interchange
1 Scope
This Standard specifies a concept and data format for representation of fingerprints using the fundamental notion of minutiae. The data format is generic, in that it may be applied and used in a wide range of application areas where automated fingerprint recognition is involved. No application-specific requirements or features are addressed in this standard. The Standard contains definitions of relevant terms, a description of where minutiae shall be defined, a data format for containing the data, and conformance information.
2 Conformance
A system conforms to this standard for producing data interchange records if it satisfies the mandatory and implemented optional requirements herein for extraction of minutiae from a fingerprint image as specified in Clause 6 and the generation of a data interchange record as specified in Clause 7. A system conforms to this standard for using data interchange records if it can parse data interchange records that conform to Clause 7. A data record conforms to this standard if it satisfies the mandatory, and optional, if implemented, requirements for structure and content as specified in Clause 7.
3 Normative References
The following standards contain provisions which, through reference in this text, constitute provisions of this American National Standard. All standards are subject to revision, and parties to agreements based on this American National Standard are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below. ANSI/NIST-ITL 1 -2007, Standard Data Format for the Interchange of Fingerprint, Facial, & Other Biometric Information ANSI INCITS 398-2008, Common Biometric Exchange Formats Framework (CBEFF)
6.1 General
This clause defines the placement of minutiae on the fingerprint. Compatible minutiae extraction is required for interoperability between different finger matchers for the purposes of matching an individual against a previously collected and stored finger record. The interoperability is based on defining the finger minutiae extraction rules and record format that are common to many finger matchers for acceptable matching accuracy, while allowing for extended data to be attached for use with equipment that is compatible with it.
6.2 Principle
Establishment of a common feature-based representation must rest on agreement on the fundamental notion for representing a fingerprint. A significant number of technology providers follow a traditional approach of encoding a fingerprint through location of “minutiae”. These minutiae are points located at the places in the fingerprint image where friction ridges end or split into two ridges. Describing a fingerprint in terms of the location and direction of these ridge endings and splits provides sufficient information to reliably determine whether two fingerprint records are from the same finger. Fingerprint images may be represented with “dark ridges” or (less commonly) “light ridges”. The minutiae shall be located in such a way that their locations and their directions do not change when the light and dark polarity of the image is inverted. This decision not only provides for consistent data extraction regardless of image polarity, but also ensures equal behavior of ending and ridge ending points with respect to image degradations such as noise and contrast variance. The specifications of minutia location and minutia direction described below accomplish this. Figure 2 and Figure 3 are illustrations of minutia placement on a ridge ending and ridge bifurcation respectively. In Figure 2 through Figure 7, and Figure 1 0 through Figure 1 3, the shaded areas of the illustrations represent the ridges of a fingerprint.