Point of interest

from Wikipedia, the free encyclopedia

Point of Interest (POI) ("place of interest", also "place of interest" (POI) ) is a term used in connection with navigation systems and route planners .

POIs are point-like geographic objects that could be important for the user of a map or a navigation system. The corresponding objects in the real world have been generalized into points for simplified representation and more economical data processing . Usually, the user is offered a large number of items on various subject areas, so-called categories. The data density and spatial coverage as well as the number of different categories depend on the type of application and the needs of the user. POI categories can be oriented towards the satisfaction of daily needs or deal with travel-specific needs, such as: B. gastronomy, accommodation, petrol stations, ATMs or parking garages. Other categories can offer points of interest to points of contact in urgent situations, such as car repair shops, pharmacies or hospitals, or they represent tourist attractions and leisure activities, including cinemas, sports stadiums, museums and other sights .

Since its position on the earth's surface is precisely described by a geographic coordinate , a point of interest can be displayed as an icon on a map . In addition, additional information such as a description, opening times, postal address and telephone number can be stored for each POI. The points can also be enhanced with multimedia information such as photos, audio files and video clips. Depending on the equipment, navigation systems offer additional options to indicate such places visually or acoustically when you approach them.

Particularly prominent points are called landmarks and are used for orientation.

File formats

There are many different file formats for storing POI data, even if the same underlying coordinate system ( WGS84 ) is used. Some of the reasons why so many variations exist to store the same data are:

  • a lack of standards in this area ( GPX is a noteworthy attempt to create such a standard),
  • the attempt by some software providers to conceal their data in order to make unlawful use by third parties more difficult,
  • Licensing issues that prevent the file specifications from being used by competitors,
  • Storage problems, e.g. B. by converting floating point number coordinates (latitude and longitude) into smaller integer values,
  • Speed ​​and battery life (displaying longitude and latitude as an integer is less CPU intensive than a floating point number),
  • the need to append own attribute fields to the data.

File formats that are used to exchange POI data:

Other providers provide converters that can convert the POI file formats into one another (e.g. GPSBabel ).

Web links

  • Wikipedia POI Thematic compilation of Wikipedia POI (source: Wikipedia lists of pyramids, racetracks, football stadiums, ...)