Vector map – Wikipedia, the free encyclopedia

The Vector Map (VMAP), also called Vector Smart Map, is a vector-based collection of geographic information system (GIS) data about Earth at various levels of detail. Level 0 (low resolution) coverage is global and entirely in the public domain. Level 1 (global coverage at medium resolution) is only partly in the public domain. Features and data attributes are tagged utilizing the international Feature and Attribute Coding Catalogue (FACC). The vector map product are usually seen as being of three different types: low resolution (level 0), medium resolution (level 1) and high resolution (level 2). Level 0 provides worldwide coverage of geo-spatial data and is equivalent to a small scale (1:1,000,000). The data are offered either on CD-ROM or as direct download, as they have been moved to the public domain. Data are structured following the Vector Product Format (VPF),[1] compliant with standards MIL-V-89039 and MIL-STD 2407 Level 1 data are equivalent to a medium scale resolution. Level 1 tiles follow the MIL-V-89033 standard. VMAP Level 1 is divided in 234 geographical tiles. Only 57 of them are currently (2006) available for download from NGA.[2] Among the available datasets, coverage can be found for parts of Costa Rica, Libya, United States, Mexico, Iraq, Russia, Panama, Colombia and Japan. Level 2 data are equivalent to a large scale resolution. Level 2 tiles follow the MIL-V-89032 standard. The USA Freedom of Information Act and the Electronic Freedom of Information Act guarantee access to virtually all GIS data created by the US government. Following the trend of the United States, much of the VMAP data has been offered to the public domain. But many countries consider mapping and cartography a state monopoly, for such countries, the VMAP Level1 data are kept out of the public domain. With the privatization of public agencies, some data are sold for a profit. Various public groups are making efforts to have all VMAP1 data moved to the public domain in accordance with FOIA [3] Further steps have been taken by the Free World Maps Foundation and others to have the data licensed under the GNU General Public License, while remaining copyrighted, as an alternative to the public domain. This is an ongoing debate (as of 2006). The U.S. government has released the data into public domain, with the following conditions imposed (quotation from VMAP0 Copyright Statement): However, all is not quite what it seems. There is a 'readme1.txt' file located in the v0eur, v0sas, and v0soa directories. This file contains information saying that layers: Boundaries Coverage and the Reference Library, are copyrighted to the Environmental Systems Research Institute. VMAP (level 0) is a slightly more detailed reiteration of the DCW. VMAP (level 1) has much higher resolution data. Source.

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Last Modified: April 23, 2016 @ 9:07 am