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Demonstration of Orthophotographic Representation and Analysis, Final Research Report, Revised November 2001

NCJ Number
Date Published
November 2001
57 pages
This report describes alternative methods of displaying crime data in the context of geographic information systems.
In a collaborative project on Orthophotographic Representation and Analysis, the University of Maryland Baltimore County and the Baltimore County Police Department sought to introduce and evaluate the use of digital aerial orthophotography as a complement to the linear and relatively featureless streets basemaps in common use in law enforcement and elsewhere. In addition, the project sought to compile, integrate, and distribute spatially-enabled data for use at the precinct level; examine the utility of global positioning systems (GPS) technology in the police department as an alternative to conventional address matching, or geocoding; and evaluate the effectiveness of orthophotos as tools, based on interviews with 24 police officers. The project resulted in several positive outcomes: (1) the practical application of digital aerial photography and associated coverages, notably building footprints, was demonstrated in the context of a large police agency; (2) this capability was supplemented with GPS technology capable of enhancing the positional accuracy of crime incident information by removing dependence on street addresses for coding and mapping incident data; (3) it showed that incident data could be enriched through improvements in the visualization of incident location and context; (4) it demonstrated that maps or photographs alone provide insufficient contextual information in combination, the benefits of synergy become apparent; (5) in a survey of a small sample of police officers, reactions to a comparison between aerial photographs and conventional digital maps generally favored the former; and (6) it demonstrated the feasibility of assembling a compendium of digital, spatially-enabled crime and collateral data that can be made accessible to anyone in a police agency either through a network or at stand-alone work stations. Figures, notes, table, appendixes

Date Published: November 1, 2001