Vector Map

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Vector Map (VMAP), AKA Vector Smart Map, is a vector based collection of GIS data covering the earth at various detail levels. Level 0 (low resolution) coverage is global, and is entirely in the public domain. Level 1 (global coverage at medium resolution) is only partly in the public domain.

1 Description
- 1.1 Thematic data layers
2 Levels of resolution
3 Debate about availability of data
4 Copyrights
- 4.1 VMAP0
5 Tools to read and convert VMAP data
6 History
7 See also
8 References
9 External links

[edit] Description

Coordinate reference system: Geographic coordinates stored in decimal degrees with southern and western hemispheres using a negative latitude and longitude
Horizontal Datum: World Geodetic System 1984 (WGS 84).
Vertical Datum: Mean Sea Level.

[edit] Thematic data layers

Features and data attributes are tagged utilizing the international Feature and Attribute Coding Catalogue (FACC).

major road networks
railroad networks
hydrologic drainage systems
utility networks (cross-country pipelines and communication lines)
major airports
elevation contours
coastlines
international boundaries
populated places
index of geographical names

[edit] Levels of resolution

The vector map product comes in three flavors: low resolution (level 0), medium resolution (level 1) and high resolution (level 2).

[edit] Level Zero (VMAP0)

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

[edit] Data sets

The entire coverage has been divided into four data sets:

North America (NOAMER)
Europe and North Asia (EURNASIA)
South America, Africa, and Antarctica (SOAMAFR)
South Asia and Australia (SASAUS).

[edit] Level One (VMAP1)

Level 1 data are equivalent to a medium scale resolution. Level 1 tiles follow the MIL-V-89033 standard.

Horizontal accuracy: 125-500m
Vertical accuracy: 0.5-2m

[edit] Data sets

VMAP Level 1 is divided in 234 geographical tiles. Only 55 of them are currently (2006) available for download from NGA ^[2]. Amongst the available datatsets, coverage can be found for parts of:

[edit] Level Two (VMAP2)

Level 2 data are equivalent to a large scale resolution. Level 2 tiles follow the MIL-V-89032 standard.

Horizontal accuracy: 125-500m
Vertical accuracy: 0.5-2m

[edit] Debate about availability of data

The 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.

Still many countries consider mapping and cartography a state monopoly; for such countries, the VMAP Level1 data are kept off the public domain. With the privatization of public agencies, some data are sold for a profit.

Efforts are being made by various public groups towards moving all VMAP1 data to the public domain in accordance with FOIA ^[3]

Further steps have been taken (by the Free World Maps Foundation among others) to licence the data under GNU Public Licence, as an alternative to plain public domain (that can be copyrighted when slightly changed). This is an ongoing debate (as of 2006), of which the outcome is yet to be seen.

[edit] Copyrights

[edit] VMAP0

The U.S. government has released the data into public domain, with the following conditions imposed (quotation from VMAP0 Copyright Statement):

As an agency of the United States government, NIMA makes no copyright claim under Title 17 of the United States Code with respect to any copyrightable material compiled in these products, nor requires compensation for their use.

When incorporating the NIMA maps into your product, please include the following:

a. "this product was developed using materials from the United States National Imagery and Mapping Agency and are reproduced with permission",

b. "this product has neither been endorsed nor authorized by the United States National Imagery and Mapping Agency or the United States Department of Defense".

With respect to any advertising, promoting or publicizing of this product, NIMA requires that you refrain from using the agency's name, seal, or initials.

The VMAP0 download page^[4] states:

Internal data reference to the CD-ROM being "LIMITED DISTRIBUTION" should be ignored.

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, contain the intellectual property of Environmental Systems Research Institute.

If these copyrighted layers are not used there is no violation of any copyrights.

[edit] Tools to read and convert VMAP data

VPFView (V2.1) - developed by NIMA, is available from NGA or USGS (as part of the NIMAMUSE package^[5]); this tool can render simple plots and export GIS data to other GIS file formats
"OGR with ODGI driver"^[6]: this free software tool can convert VMAP format to standard GIS file formats such as SHAPE, PostGIS etc.

[edit] History

National Geospatial Intelligence Agency

1991-1993: The National Imagery and Mapping Agency (NIMA) develops the Digital Chart of the World (DCW) ^[7] for the US Defense Mapping Agency (DMA) with themes including Political/Ocean Populated Places, Railroads, Roads, Utilities, Drainage, Hypsography, Land Cover, Ocean Features, Physiography, Aeronautical, Cultural Landmarks, Transportation Structure and Vegetation. One of the sources for the data was the Operational Navigation Chart that compiles military mapping from Australia, Canada, United Kingdom, and the United States.

VMAP (level 0) is a slightly more detailed reiteration of the DCW.
VMAP (level 1) has much higher resolution data.

2004 The National Imagery and Mapping Agency (NIMA) is renamed to National Geospatial-Intelligence Agency which will incude other mapping agencies such as the Defense Mapping Agency (DMA), the Central Imagery Office (CIO) and the Defense Dissemination Program Office (DDPO). All VMAP data will subsequently be distributed through the NGA.