3.3 Fingerprint image acquisition

This section specifies the capture of a full set of fingerprint images for PIV registration. A subject's fingerprints shall be collected according to any of the three imaging modes enumerated in Table 1.

Table 1: Fingerprint acquisition protocols

Option 1 – Required presentations for plain live scan Combined plain impression of the four fingers on the right hand (no thumb) Combined plain impression of the four fingers on the left hand (no thumb) Combined impression of the two thumbs Option 2 – Required presentations for rolled live scan 10 separately rolled fingers Combined plain impression of the four fingers on the right hand (no thumb) Combined plain impression of the four fingers on the left hand (no thumb) Left thumb plain impression Right thumb plain impression These captures may be simultaneous (two thumbs next to each other) or sequential (one thumb at a time) Option 3 - Required presentations for rolled ink on card 10 separately rolled fingers Combined plain impression of the four fingers on the right hand (no thumb) Combined plain impression of the four fingers on the left hand (no thumb) Left thumb plain impression Right thumb plain impression These captures may be simultaneous (two thumbs next to each other) or sequential (one thumb at a time)

INFORMATIVE NOTES: 1. There is no requirement that the order specified above is the order in which the images must be acquired. 2. The combined multi-finger plain-impression images are also referred to as slaps or flats. They are obtained by simultaneous placement of multiple fingers on the imaging surface without specific rolling movement. 3. Options 2 and 3 represent existing agency practice. Although Option 1 is now acceptable to the FBI agencies may need to implement Options 2 or 3 for transmission via the Office of Personnel Management. For Options 1 and 2 the devices used for capture of the fingerprints shall have been certified by the FBI to conform to Appendix F of the FBI’s Electronic Fingerprint Transmission Specification [EFTS, Appendix F]. For Option 3, a scan of the inked card shall be performed to effect conversion to electronic form. The scanner shall be certified by the FBI as being compliant with [EFTS, Appendix F]. The scanning is needed to produce fingerprints in the digital format described in Section 3.5 and thereby Section 3.6. The FBI specifications include width and height specifications for the imaging surface. The native scanning resolution of the device shall be 197 pixels per centimeter (500 pixels per inch) in both the horizontal and vertical directions. These specifications comply with the FBI submission requirements and with the Image Acquisition Setting Level 31 of the Finger Image-Based Data Interchange Format standard, INCITS 381 [FINGSTD]. The procedure for the collection of fingerprints, presented in Table 2, shall be followed. The procedure shall employ the NIST Fingerprint Image Quality [NFIQ] algorithm to initiate any needed reacquisition of the images. An attending official shall be present at the time of fingerprint capture. The agency shall employ measures to ensure the quality of acquisition and guard against faulty presentation, whether malicious or unintentional. Such activity might be an integral function of the acquisition device or might be implemented by the attending official. In any case, the agency shall ensure that the applicant does not swap finger positions or hands, occlude fingers, or misalign or misplace the fingers. Particularly, because it is common during collection of multi-finger plain impressions for fingers 05 and 10 to not be long enough to reach the imaging platen, it is accepted practice for the hand be placed at an angle to the horizontal to ensure imaging of all four fingers. Although this is not needed with newer, large-platen, devices the official shall in all cases take care to image all fingers completely. The procedure requires segmentation of the multi-finger plain impressions; this operation may be assisted by the attending official.

Table 2: Quality control procedure for acquisition of a full set of fingerprint images

Step Action 1. Attending official should inspect fingers and require absence of foreign material. 2. Official should ensure imaging surface of the sensor, or the card, is clean. 3. Acquire fingerprints according to Option 1, 2, or 3 in Table 1. For Option 3, scan the inked card using [EFTS, Appendix F] certified scanner.

4. Segment the multi-finger plain impression images into single-finger images. Automated segmentation is recommended. Attending official should inspect the boundaries of the automatic segmentation and correct any failures, perhaps via an interactive graphical user interface. 5. Compute NFIQ value for thumbs and index fingers. If all have NFIQ values of 1, 2, or 3 (i.e., good quality) then go to step 8. 6. Repeat steps 2-5 up to three more times.

7. If after four acquisitions the index fingers and thumbs do not all have NFIQ values of 1, 2 or 3 then select that set, acquired in step 3 and segmented in step 4, for which the mean of the NFIQ values of the left index, right index, left thumb, and right thumb is minimum (i.e. of best quality). If all of the index finger and thumb quality values are unavailable (perhaps because of injury to one or more of those fingers) then use the last set from step 3 of those fingers that are available, without any application of NFIQ. 8. Prepare and store the final records per Sections 3.4, 3.5, and 3.6

Ordinarily, all ten fingerprints shall be imaged in this process; however, if one or more fingers are not available (for instance, because of amputation) then as many fingers as are available shall be imaged. When fewer than ten fingers are collected, the FBI background transaction of Section 3.4 requires (in field AMP 2.084 of an accompanying Type 2 record) the labeling of those fingers that are amputated or otherwise not imaged; see [EFTS, Appendix C].

`3.3` Fingerprint image acquisition

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Control