Geo tagging means adding geographical location information to a photograph or video or any other data. The geographical information will be the latitude and longitude coordinates of the location where the photo graph was taken or a video was shot.
In addition to the latitude and longitude values of the location, altitude and the direction in which the photo or video was shot can also be added. The concept can be implemented as follows,
Capture device or Camera: First of all we will need a camera which will capture a picture or video. The camera chosen should provide an easy interface to access and edit the captured image/video files. The interface can be a SDCARD/USB/Serial interface.
Processor: To add the geographical location information we need to edit the captured image/video files, so we will need a processor which can read the captured data and add the geo-information to the files. We can use any good microcontroller with an camera interface(SDCARD/USB/Serial Interface). You can get a CMOS camera for this purpose.
Getting location information(GPS): We can get the location information from a Global Positioning System device abbreviated GPS. The GPS device acquires the locations information from GPS satellites in the form of latitude and longitude values and gives to the processing device.
Getting the altitude information: The height or altitude information can be got from a altitude meter or altimeter which measures the altitude of any particular location on earth with respect to the sea level. The altimeter measures the atmospheric pressure at any particular location with respect to seal level and converts it to altitude.
Getting the direction(e-Compass): The direction in which the photograph was taken can be added with the help of a magnetic compass. Electronic MEMS based compasses are available which can provide the direction information.