Page 177 - Automated Fingerprint Identification Systems (AFIS)

162 AUTOMATED FINGERPRINT IDENTIFICATION SYSTEMS

number of vendors. For these reasons, there was no opportunity for informa-
tion to be exchanged electronically.
To meet the need of a framework for the interchange of fingerprint data,
ANSI and the (then) National Bureau of Standards produced the ANSI/NBS-
ICST 1-1986 Fingerprint Identification—Data Format for the Information Exchange.
This standard and subsequent standards define the content, format, and units
of measurement for the exchange of fingerprint information between AFIS
systems and an interface with IAFIS. The standard defined four types of records
and emphasized the development of a standard minutiae encoding format. The
four record types were the following:

• Type 1: Textual data transaction type, header, file content specifications,
subject descriptive and arrest data
• Type 2: Fingerprint minutiae data
• Type 3: Fingerprint images (low-resolution: 10 pixels/mm)
• Type 4: Fingerprint images (high-resolution: 20 pixels/mm)

The 1986 standard was not widely accepted, however, because the minutiae
encoding did not accommodate existing proprietary formats. The FBI National
Crime Information Center (NCIC) Advisory Policy Board (APB) recommended
that the FBI establish a new standard for electronic image communication.
Between 1990 and 1992 government and AFIS vendors worked to develop it.
Building on the 1986 standard, the new standard, ANSI/NIST-CSL 1-1993,
incorporated a user-defined text record and created separate images for binary
(black-and-white only) and grayscale fingerprint images. It also created a user-
defined image record and addressed image compression and decompression
methods.
Following the introduction of this standard, NIST began to address the need
to accommodate SMT information as well as subject photographs (mug shots).
An addendum to the 1993 standard was created with the introduction of
ANSI/NIST-ITL 1A-1997. This standard contained a total of 10 record types:

• Type 1: Transaction information
• Type 2: Descriptive text (user-defined)
• Type 3: Fingerprint image data (low-resolution grayscale)
• Type 4: Fingerprint image data (high-resolution grayscale)
• Type 5: Fingerprint image data (low-resolution binary)
• Type 6: Fingerprint image data (high-resolution binary)
• Type 7: Image data (user-defined)
• Type 8: Signature image data
• Type 9: Minutiae data
• Type 10: Facial and SMT image data