acknowledgements for ansi/nist-itl 1-2011 - NIST Visual Image ...

ANSI/NIST-ITL 1-2011 - UPDATE 2013 DRAFT VERSIONF.6.2Overall image characteristicsF.6.2.1 Field 9.307: EFS pattern classification / PAT instructionsThis field, described in Section 8.9.7.5 , contains fingerprint classification information for theimage. This field shall only be used for fingerprints, and shall be omitted (left empty) for otherfriction ridge impressions.The first information item, general class / GCF, is the general set of pattern classifications witha value selected from Table 32 Pattern classification codes, general class column.The second information item, subclass / SUB, is the subclass of arches and whorls selectedfrom Table 32 Pattern classification codes, subclass column. This information item shall onlybe included if the sub-classification can be determined precisely.The third information item, whorl - delta relationship / WDR (also known as Whorl Tracing)may optionally be used by a human examiner or automated system to provide the relationshipbetween the deltas in a whorl. This information item shall only be included for whorls if thesubclass is known, and only if the whorl delta relationship can be determined precisely. Thisinformation item shall be set to I (Inner), O (Outer), or M (Meeting), following the guidelinesfrom The Science of Fingerprints, p. 60 (See Section 3 Normative references ): When thedeltas have been located, the ridge emanating from the extreme left delta is traced until thepoint nearest or opposite the extreme right delta is reached. The number of ridges interveningbetween the tracing ridge and the right delta are then counted. If the ridge traced passes insideof (above) the right delta, and three or more ridges intervene between the tracing ridge and thedelta, the tracing is designated as an “inner” […] If the ridge traced passes outside of (below)the right delta, and three or more ridges intervene between the tracing ridge and the delta, thetracing is designated as an “outer” […] All other tracings are designated as “meeting.”This field may include up to seven subfields, indicating all possible pattern classifications.Classification must be conservative: if the pattern is known precisely, only a single pattern shallbe indicated; however, if there is any doubt as to the precise classification, all possible patternsshall be included. If the pattern cannot be classified, but a pattern type can be definitivelyexcluded, then that shall be indicated by including all possible patterns. For example, a latentthat contains a delta but no other pattern area information could possibly be a left loop, rightloop, whorl (of any type), or tented arch, so it would indicate 4 subfields with the followinginformation items specified:general class / GCF = LSgeneral class / GCF = RSgeneral class / GCF = WUgeneral class / GCF = AU and subclass / SUB = TA492