Page 123 - Automated Fingerprint Identification Systems (AFIS)

108 AUTOMATED FINGERPRINT IDENTIFICATION SYSTEMS

transposed finger images. Livescan software can also provide a standardized list
of options from pull-down menus. This speeds the process as well as makes it
more consistent. In addition to the 14 finger images (one of each of the ten
rolled fingers, one of each of the two plain thumb impressions, and one of each
of the two remaining sets of fingers), the livescan can capture images of each
of the two palms, as well as mug shots.
When the quality of the images has been approved and the data fields are
complete, the record is electronically sent to the state and/or local identifica-
tion bureaus. The record arrives at a “store and forward” server, where one
copy is retained (stored) for search by the identification agency, and one copy
is sent (forwarded) to IAFIS. The livescan device must meet the ANSI/NIST
transmission standards for the data to be electronically forwarded through
the AFIS and onto IAFIS; those agencies that are not fully compliant can
forward the records to the FBI by mail. The livescan must also meet the FBI
transmission specifications (EFTS) as well as any state or local EFTS, and it
must comply with the FBI’s wavelet scalar quantization (WSQ) grayscale
fingerprint image compression specification. NIST transmission standards
specify the record type and what is included in the record, for example, a finger
image captured at 1,000ppi. The FBI transmission specifications indicate the
fields that must accompany that record, e.g., last name, first name, etc. WSQ
specifies the compression and decompression of the image needed for elec-
tronic transmission. (Virtually all images are compressed and decompressed to
permit reasonable transmission speeds.) States may add additional fields to the
FBI EFTS in order to incorporate items of interest, such as the name of the
county.
If the finger images were taken on a physical card with ink, once completed,
either the card is sent to the state identification agency via mail or fax or the
card is scanned and the record is electronically sent to the state agency. Once
the record is received, the images can be matched to a record already created
from the OLBS information. The images and data elements are assembled elec-
tronically into a single record that is sent to the store and forward server as
described above.

5.3 AFIS NAME AND MINUTIAE SEARCHES

Once the state identification agency receives the record from the store and
forward server, it may initiate two searches: a name search, which compares the
name on the record with the names in the Master Name Index (MNI), and an
AFIS minutiae search, which is based on image characteristics (see Fig. 5.11 for
an overview). The search of the MNI produces a list of candidates and SID
numbers.