Coverage data

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In geographic information systems, a coverage is a mapping of one aspect of data in space. It represents a "domain" (the universe of extent) in terms of characteristics expressing a range of values. For example: a satellite image derived from remote sensing might record varying degrees of light pollution. Aerial photography, land cover data, and digital elevation models are all considered coverage data.

As a contrast to coverage data we find feature data, which concentrates more on the numerous characteristics of a spot and less on its spatial surrounds.

[edit] GIS Format

"Coverage" is the term typically applied to the legacy Arc/INFO format developed by ESRI. The Coverage Model was a revolutionary concept, extending CAD formats into more spatially aware data that featured linked attributes. Coverages processed using the BUILD and CLEAN commands are 2D planar datasets that maintain topological information, e.g. a polygon "knows" which segments of its perimeter are shared with adjacent polygons. Due to the lack of processing power in computing at the time of its development, the Coverage model employs indexed binary files to store spatial and attribute data separately as opposed to utilizing a RDBMS[1].

[edit] Web Coverage Service

Coverage may also refer to WCS, a protocol for delivering coverage data.

[edit] References

  1. ^ Zeiler, Michael. Modeling Our World, The ESRI Guide to Geodatabase Design. ESRI Press, 1999. ISBN 1879102625