Introduction
Geographic Data File ( GeographicalDataFile, GDF ) is a file format that holds geographic data for describing and Transport road networks and road related data. Compared to traditional GIS data formats, GDF provides more detailed rules for the acquisition classification of data and standard features, attributes, and relationships.
GDF is originally used in the car navigation system, but it is also very effective for other transportation and transportation applications, such as fleet management, scheduling management, road traffic analysis, traffic management, and vehicle automatic positioning.
GDF is encoded with ASCII and saves in a single file. Each GDF is divided into multiple partitions, and the partition includes an information unit and a carrier unit. The information unit includes information of the specific data in the carrier unit, and the carrier unit consists of Volume and Album, and Volume is a basic data organization unit, which is synthesized in Album.
Since the GDF format is a plain text format, it is rarely applied directly to a large geographic application, and it is often necessary to convert to a more efficient file format.
The map of some map vendors is also available in GDF format, such as Navteq and Teleatlas.
Standardized
GDF is European standards, which is drafted by the European Standards Committee (EuropeanCommitteeforstandardization, Cen). Data map manufacturers, automobiles and electronic equipment manufacturers. The results of these standardized work (CENGDF3.0) later became the main source of ISOGDF4.0 established by ISO / TC204 3rd Working Group. ISO also uses GDF as a database standard for IntelligentTransportsystems, ITSs.
However, although ISO's GDF standard already exists, most vendors use their own GDF format. As of 2007, the interoperability between these formats still has problems
-
car navigation system (En: AutomotiveNavigationSystem)
-
navigation (En: navigation)
-
Global Positioning System (GPS)
-
geographic tag Language (en: geographymarkuplanguage)
-
Keyhole Markup Language (En: KeyholeMarkUplanguage)
-
Map Resource Database Management (EN: MAPDATABASEMANAGEMENT