Point of interest

point of interest , or POI , is a specific location that someone may find useful or interesting. An example is a spot on the Earth Representing the rental of the Space Needle , gold is no one Mar. Representing the rental of the mountain , Olympus Mons . Most users use the term when referring to hotels, campsites, fuel stations or any other categories used in modern (automotive) navigation systems . In medical fields such as histology / pathology / histopathology , points of interest are selected from the general background in a field of view ; For example,

A region of interest (ROI) and a volume of interest (VOI) are similar in concept, denoting a region or a volume.

The term is widely used in cartography , especially in electronic variants including GIS , and GPS navigation software . In this context the synonym waypoint is common.

A GPS point of interest specifies, at minimum, the latitude and longitude of the POI, assuming a certain map datum . A name or description for the POI is usually included, and other information may also be attached. GPS applications typically use icons to represent different categories of POI on a map graphically. [1]

POI collections

Custom speed camera POI overlaid on a BMW navigation map

Digital maps for modern GPS devices typically include a basic selection of POIs for the map area. [2]

HOWEVER websites exist That specialize in the collection, verification, management and distribution of POIs qui end-users can load onto Their devices to replace or supplement the Existing POIs. [3] [4] While some of these websites are generic, and will collect and categorize GPS devices (eg TomTom / Garmin ). End-users also have the ability to create their own custom collections.

Commercial POI collections, Especially Those That ship with digital maps, are sold or That was subscription basis are usually protected by copyright . HOWEVER, there are aussi Many websites from qui royalty-free POI collections Can Be Obtained, eg PBMD – Smart Points of Interest , qui est distributed under ODbL license. [5]


The applications for POI are extensive. As GPS-enabled devices as well as software applications that use digital maps become more available, so too the applications for POI are also expanding. Newer digital cameras for example can automatically tag a photograph using Exif with the GPS rental WHERE a picture was taken; Then thesis pictures can be overlaid as POI was digital map or satellite imagery Such As Google Earth . Geocaching applications are built around POI collections. In Vehicle Tracking Systems POIs are used to mark points and / or offices to users of GPS tracking software .

File formats

Many different file formats , including proprietary formats , are used to store WGS84 system is used.

Reasons for variations to store the same data include:

  • A lack of standards in this area ( GPX is a notable attempt to address this).
  • Attempts by some software vendors to protect their data through obfuscation .
  • Licensing Issues that prevent companies from using competitor’s file specifications.
  • Memory saving, for example, by converting floating point latitude and longitude co-ordinates into smaller integer values.
  • Speed ​​and battery life (operations using integer latitude and longitude values ​​are CPU- intensive than those that use floating point values).
  • Requirements to add custom fields to the data.
  • Use of older reference systems That predate GPS (for example UTM or the British national grid reference system )
  • Readability / possibility to edit (plain text files are human-readable and may be edited)

The Following are the file formats Reviews some of used by different vendors and devices to exchange POI (and In Some boxes aussi tracks navigation ):

  • ASCII Text (.asc .txt .csv .plt)
  • Topografix GPX (.gpx)
  • Garmin Mapsource (.gdb)
  • Google Earth Keyhole Markup Language (.kml .kmz)
  • Pocket Street Pushpins (.psp)
  • Maptech Marks (.msf)
  • Maptech Waypoint (.mxf)
  • Microsoft MapPoint Pushpin (.csv)
  • OziExplorer (.wpt)
  • TomTom Overlay (.ov2) and TomTom plain text format (.asc)
  • OpenStreetMap data (.osm)

Third party and vendor-supplied utilities are available to convert the point of interest data [6] entre different formats to allow ’em to be Exchanged entre Otherwise compatible GPS devices or systems. [7] In addition , many applications will support the generic ASCII text file format, although this format is more prone to error due to its loose structure as well as the co-ordinates can be represented (eg decimal vs degree / minute / second). (KML to GPX converters) and KML2OV2 (KML to OV2 converts).

See also

  • Automotive navigation system
  • Geocoded photograph
  • Map database management
  • OpenLR
  • Tourist attraction
  • World Geodetic System (Used to represent GPS co-ordinates)


  1. Jump up^ “Garmin POI Loader” . Garmin . Retrieved 2008-01-17 .
  2. Jump up^ “TomTom Points of Interest” . POI66.
  3. Jump up^ “Waypointer – online POI manager” . Waypointer.
  4. Jump up^ “Pintica – online POI manager” . Pintica.
  5. Jump up^ Čerba, Otakar (23 February 2016). “SPOI” (PDF) . SDI4Apps. p. 4 . Retrieved 28 March 2016 .
  6. Jump up^ CamperVanNZ. “Convert POI (Online)” .
  7. Jump up^ RJ Davies. “POIConverter” . Retrieved 2008-01-18 .

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