Sustainability of Digital Formats: Planning for Library of Congress Collections |
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Introduction | Sustainability Factors | Content Categories | Format Descriptions | Contact |
Full name | Vector Product Format (VPF) |
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Description | The Vector Product Format (VPF) is a standard data structure developed in 1996 as a U.S. Military Standard for geospatial data based on a georelational data model. It is designed to be compatible with a widevariety of applications and products and to allow application software to read data directly from computer-readable media without prior conversion to an intermediate form. VPF uses tables and indexes that permit direct access by spatial location and thematic content and is designed to be used with any digital geographic data in vector format that can be represented using nodes, edges, and faces. A VPF-compliant database product must include all mandatory tables and columns described in section 5 of the specification. The VPF data model may be considered to be layered into four structural levels. At the lowest level, a VPF database consists of feature classes. In the database, these feature classes are defined using VPF primitive and attribute tables. Feature classes make up coverages, which in turn make up libraries; and finally, a database is made up of libraries. |
Production phase | Georelational data model intended for direct use. |
LC experience or existing holdings | |
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LC preference |
Disclosure | Unclassified United States military standard. |
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Documentation | Military Standard, Vector Product Format, MIL-STD-2407 28 June 1996. Each VPF product is defined by a separate product specification referring to the RPF standard. |
Adoption |
Approved for use by all Departments and Agencies of the Department of Defense, including the US Defence Mapping Agency for the distribution of its vector data sets . National Geospatial-Intelligence Agency (NGA)'s Digital Nautical Chart is an unclassified, vector-based digital database containing maritime significant features essential for safe marine navigation produced in the standard Vector Product Format (VPF) allowing for modeling real world features in digital geographic databases. The Digital Nautical Chart database uses a table based georelational data model and supports GIS applications such as mission planning, command and control, and situational awareness. The original World Vector Shoreline (WVS) was a digital data file containing the shorelines, international boundaries, and country names of the world. The National Imagery and Mapping Agency, now the National Geospatial-Intelligence Agency (NGA)'s WVS data were processed into NGA’s Vector Product Format in 1995, resulting in the highest resolution demarcation of coastline then globally available, the World Vector Shoreline Plus. See the Vector Product Format (VPF) World Vector Shoreline (WVSPLUS) Draft Specification (MIL-PRF-89012A dated August 24, 1999) for a detailed product definition. More recent shoreline data is distributed in other formats, in particular as shapefiles (ESRI_shape). A few software applications can read VPF files, including: OGDI Vectors driver for GDAL; MapLink Pro; and ESRI ArcGIS. See Working With Vector Product Format (VPF) - APIs, etc. |
Licensing and patents | Trademarked by the National Geospatial-Intelligence Agency |
Transparency | VPF allows application software to read data directly from the storage medium without prior conversion to another format. VPF uses tables and indexes that permit direct access to thematic content. |
Self-documentation | |
External dependencies | |
Technical protection considerations |
GIS images and datasets | |
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Support for GIS metadata |
VPF provides a number of options for encoding data quality information. The information itself can be encoded at any level within the VPF structure depending upon its basic thematic and spatial characteristics. VPF data producers are encouraged to make use of the data quality table whenever possible. In instances where DQ characteristics vary spatially, the use of data quality coverages is strongly recommended. VPF contains a self-defining data dictionary that permits user understanding of features and their attributes. A VPF database may contain seven types of data quality information: source, positional accuracy, attribute accuracy, date status, logical consistency, feature completeness, and attribute completeness. , Definitions of these quality types are provided in MIL-STD-2407 appendix E. |
Tag | Value | Note |
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Filename extension | See note. | VPF uses only three types of files: directories, tables, and indexes. Certain table, directory, and filename extensions are reserved; see Notes. |
General |
VPF is a trademark of the National Geospatial-Intelligence Agency. The specification reserves certain names for tables, coverage directories, and table name extensions. These are specified in tables 13, 14, and 15 on pages 53-55. Reserved file names
Reserved directory names
Reserved table name extensions
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History |
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