Understanding Geotagging In Photos

When you take photos with your smartphone camera, you are not only capturing the image. In fact, you are also capturing data that contains plenty of information about the image. This is called the metadata, and is contained in your image’s file called EXIF (Exchangeable Image File Format). The EXIF contains information about details of your photo, like the following:

  • Date and Time
  • Name of the file
  • Size of the file
  • Image resolution
  • Smartphone model
  • Aperture
  • Shutter speed
  • Focal length
  • ISO

Now those are the basic information recorded. Another thing the EXIF metadata can store is the location of where you took that photo. This uses the GPS coordinates of latitude and longitude taken from your smartphone. When you set your smartphone (whether it is using Android or iOS) to track your location, then it will use the GPS system to record your coordinates. Certain apps make use of this information, including social media.

When you enable Location Services on your smartphone (Android)

Certain DSLR and mirrorless cameras can also record GPS coordinates if they have access to a GPS network. The smartphone has the capability to connect to a GPS network like GALILEO or A-GPS. These make use of both terrestrial and satellite radio transmission to send information back to the smartphone that contains the latitude and longitude of the location where the photo was taken.

For example, if you want to visit the exact location on a navigation system you would have to either type the name or to be more exact enter the GPS coordinates like so:

34.013627, -118.493787 (Decimal Degrees)

34°00'49.058"N 118°29'37.632"W (Degrees, Minutes, Seconds)

This can also be searched using a map application for GPS. This is the type of metadata smartphones can record on an image that is stored in the file’s EXIF. You can easily see this by checking your file’s properties by right-clicking in Windows and selecting ‘Properties’ or selecting the image file and clicking with two-fingers and the ‘Get Info’ option.

An example of EXIF metadata using Adobe Photoshop.

The process of including GPS coordinates of the image is called geotagging. This is actually useful for tagging locations in social media apps and a way for any smartphone app to track a user’s whereabouts for things like check-in and perhaps to determine the most optimal server to connect to. Facebook and Instagram are examples of social media apps that make use of this feature.

Now what about photos that you upload that don’t contain GPS coordinates, but how does the app you are using still determine the location?

I have an example of this, because it is actually still possible to get that information even though it wasn’t recorded as metadata on the image. Instead, the app you are using is the one that gets the location for you. So my example for this would be Google.

Here is a copy of the image I took with a smartphone.

Here is the metadata information of the photo, on a MacOS.

EXIF metadata of the image.

Notice that there are no GPS coordinates stored anywhere in the metadata. Now here is the image details when uploaded to Google photo gallery.

So there is a ‘Location’ section that gives the approximate location of where the photo was taken, and it is correct.

How is this possible?

No cause for alarm. There are 3 ways Google knows the location of your photos:

1.Your camera’s GPS saves your location.

2. Google Photos might estimate a location using information such as your Google Location History (if turned on), which is stored in your Google Account. Check your Google Location History. You can edit or remove a location that was estimated by Google Photos.

3. You added a location.

I neither used GPS on the smartphone to save the coordinates nor did I add the location myself. That leaves option 2, which is Google Photos estimated the location based on Location History, which I had enabled on the phone. This was how it got geotagged when uploaded to Google Photos.

If this is a security concern, especially if you are publicly sharing photos, you can stop Google Photos from including the location. Follow these steps:

  1. On your Android phone or tablet, open the Google Photos app.
  2. Tap Menu -> Settings
  3. Remove geo location. Anything that you share using a link won’t have a location.

Note:

  • If you share a photo or video in a different way, for example, downloading and emailing it to someone, it may still have the location.
  • If you’ve already shared the photo or video using a link before you changed this setting, it will still show the location.

Geotagging can be helpful if you want to document your travels. Travel photographers, smartphone or DSLR, can enable GPS coordinates to recorded as metadata in their files. When it comes to privacy concerns, it may not be required. You can also stop your devices or apps from recording your location.

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Vincent Tabora

Vincent Tabora

Editor HD-PRO, DevOps Trusterras (Cybersecurity, Blockchain, Software Development, Engineering, Photography, Technology)