Product Code Database
Geotagging, or GeoTagging, is the process of adding geographical identification metadata to various media such as a geotagged photograph or video, websites, SMS messages, QR Codes or RSS
Geotagging can help users find a wide variety of location-specific information from a device. For instance, someone can find images taken near a given location by entering latitude and longitude coordinates into a suitable image search engine. Geotagging-enabled information services can also potentially be used to find location-based news, websites, or other resources. Geotagging can tell users the location of the content of a given picture or other media or the point of view, and conversely on some media platforms show media relevant to a given location.
The geographical location data used in geotagging can, in almost every case, be derived from the global positioning system, and based on a latitude/longitude-coordinate system that presents each location on the earth from 180° west through 180° east along the Equator and 90° north through 90° south along the prime meridian.
The related term geocoding refers to the process of taking non-coordinate-based geographical identifiers, such as a street address, and finding associated geographic coordinates (or vice versa for reverse geocoding). Such techniques can be used together with geotagging to provide alternative search techniques.
Facebook users can geotag photos that can be added to the page of the location they are tagging. Users may also use a feature that allows them to find nearby Facebook friends by generating a list of people according to the location tracker in their mobile devices.
Instagram uses a map feature that allows users to geotag photos. The map layout pin points specific photos that the user has taken on a world map.
In order to capture GPS data at the time the photograph is captured, the user must have a camera with built in GPS or a standalone GPS along with a digital camera. Because of the requirement for wireless service providers in United States to supply more precise location information for 911 calls by September 11, 2012, more and more cell phones have built-in GPS chips. Most smart phones already use a GPS chip along with built-in cameras to allow users to automatically geotag photos. Others may have the GPS chip and camera but do not have internal software needed to embed the GPS information within the picture. A few digital cameras also have built-on or built-in GPS that allow for automatic geotagging.
Devices use GPS, A-GPS or both. Assisted GPS can be faster getting an initial fix if within range of a cell phone tower, and may work better inside buildings. Traditional GPS does not need cell phone towers and uses standard GPS signals outside of urban areas. Traditional GPS tends to use more battery power. Almost any digital camera can be coupled with a stand-alone GPS and post processed with photo mapping software, to write the location information to the image's exif header.
GEO_LOCATION=(decimal latitude);(decimal longitude);([optional]elevation in meters)
for example:
GEO_LOCATION=35.1592;-98.4422;410
The similar Geotag format allows the addition of place name and region tags:
50.167958;
-97.133185
A proposal has been developed to extend Geo to cover other bodies, such as Mars and the Moon.
An example is the Flickr photo-sharing Web site, which provides geographic data for any geotagged photo in all of the above-mentioned formats.
geotagged
geo:lat=57.64911
geo:lon=10.40744
This describes the geographic coordinates of a particular location in terms of latitude (<nowiki></nowiki>) and longitude (<nowiki></nowiki>). These are expressed in decimal degrees in the WGS84 datum, which has become something of a default geodetic datum with the advent of GPS.
Using three tags works within the constraint of having tags that can only be single 'words'. Identifying geotagged information resources on sites like Flickr and del.icio.us is done by searching for the 'geotagged' tag, since the tags beginning <nowiki></nowiki> and <nowiki></nowiki> are necessarily very variable.
Another option is to tag with a Geohash:
geo:hash=u4pruydqqvj
A further convention proposed by FlickrFly adds tags to specify the suggested viewing angle and range when the geotagged location is viewed in Google Earth:
ge:head=225.00
ge:tilt=45.00
ge:range=560.00
These three tags would indicate that the camera is pointed heading 225° (south west), has a 45° tilt and is 560 metres from the subject.
Where the above methods are in use, their coordinates may differ from those specified by the photo's internal Exif data, for example because of a correction or a difference between the camera's location and the subject's.
In order to integrate geotags in social media and enhance text readability or oral use, the concept of 'meetag' or tag-to-meet has been proposed. Differing from hashtag construction, meetag includes the geolocation information after an underscore. A meetag is therefore a word or an unspaced phrase prefixed with an underscore ("_"). Words in messages on microblogging and social networking services may be tagged by putting "_" before them, either as they appear in a sentence, (e.g. "There is a concert going _montreuxjazzfestival", "the world wide web was invented _cern _geneve", ...) or appended to it.
The progression of GPS technology, along with the development of various online applications, has fueled the popularity of such tagged blogging, and the combination of and GSM localization, has led to the , where blog posts are tagged with exact position of the user. Real-time geotagging relays automatically geotagged media such as photos or video to be published and shared immediately.
For better integration and readability of geotags into blog texts, the meetag syntax has been proposed, which transforms any word, sentence, or precise geolocalization coordinates prefixed with an underscore into a 'meetag'. It not only lets one express a precise location but also takes in account dynamically changing geolocations.
The 2009 app Cyclopedia works relatively well showing geotagged Wikipedia articles located within several miles of ones location, integrated with a street-view mode, and 360-degree mode.
The app Respotter Wiki, launched in 2009, claims to feature Wikipedia searching via a map, also allowing users to interact with people around them, via messaging and reviews, etc. The app, in its current function, however, seems to give only geotagged photo results.
As of 2017, the Wikipedia-World Project provides a simple map search tool which can display tagged articles near to a particular location, as well as a variety of more sophisticated tools integrated with external mapping services.
In 2007, four United States Army Apache helicopters were destroyed on the ground by Iraqi insurgent mortar fire; the insurgents had made use of embedded coordinates in web-published photographs (geotagging) taken of the helicopters by soldiers.
Another newly realized danger of geotagging is the location information provided to criminal gangs and poachers on the whereabouts of often endangered animals. This can effectively make tourists scouts for these poachers, so geotagging should be turned off when photographing these animals. According to Chinoitezvi Honour, some phones automatically geotag pictures hence location should be turned off when taking pictures.
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