Posts Tagged ‘gps’
The GPS Map app can turn an Android device into a handy tool for keeping track of locations you’ve already photographed or plan to photograph later. The app allows you to add so-called placemarks to the map, and you can use photos stored on your Android device as markers.
Adding a placemark in GPS Map requires several steps, but ultimately it’s a rather straightforward thing to do. Long-tap on the desired location on the map and tap Yes. Tap then Marker → Import Image. To import an existing photo, tap Gallery (or Browse) and select the desired photo.
If the selected photo contains geographical coordinates, you can attach the photo to the current placemark using the Import Image button, or you can import the photo as a new placemark by tapping on Import Image & Placemark.
Once you’ve attached the photo to the placemark, return to the Placemark Edit screen, modify the default description is necessary and tap the Confirm button to add the placemark. You should then see the placemark with a tiny thumbnail of the attached photo on the map. You can create as many placemarks as you need and use the Settings → Placemarks screen to manage existing placemarks.
GPS Map’s interface is somewhat unpolished, and the app can be slow at times, but if you are looking for a tool that can help you to track locations in an efficient manner, then the app is just the ticket.
Need to quickly geotag a bunch of photos taken at a specific location? ExifTool is your friend. Using this powerful command-line tool, you can geotag multiple photos with a single command. Before you proceed, make sure that ExifTool is installed on your machine. To install ExifTool on Ubuntu, execute the sudo apt-get install libimage-exiftool-perl command. Next, you have to obtain the longitude and latitude of the desired geographical location, and feed the coordinates to ExifTool as follows:
exiftool -GPSLongitudeRef=E -GPSLongitude=139.7513889 -GPSLatitudeRef=N -GPSLatitude=35.685 *.jpg
This command will geotag all JPEG images in the current directory. If you are running Windows, download the latest version of the ExifTool executable and rename it as in the example below:
exiftool (-GPSLongitudeRef=E -GPSLongitude=139.7513889 -GPSLatitudeRef=N -GPSLatitude=35.685).exe
Drag and drop the photos you want to geotag onto the executable and ExifTools will do the rest. Besides GPSLongitudeRef, GPSLongitude, GPSLatitudeRef, and GPSLatitude, ExifTools supports a number of other tags. Check the GPS Tags page for further info.
You don’t need a fancy camera with a built-in GPS receiver to geotag your photos. An Android device with the Open GPS Tracker app and digiKam can do the job just fine. The app lets you track your route and save it as a GPX file which you can then use to geocorrelate your photos in digiKam.
Geocorrelation is a relatively simple process which assigns geographical coordinates from the GPX file to the photos based on their time stamps. So for this technique to work its magic, you must sync the time on your Android device with your camera. When you head for a photo walk, launch Open GPS Tracker on your Android device and start a new tracking session. When you are back home, stop the tracking session, and use the Share Track button in Open GPS Tracker to save the recorded track in the GPX format on the SD card or send it via email to your machine.
Offload then the photos from your camera to digiKam, select them, and choose Image » Geolocation » Correlator. Press the Load GPX File button and select the GPX file. digiKam should then automatically assign geographical coordinates to the photos. By default, digiKam can tolerate a 30-second gap between the time settings of the camera and the GPX track. If the gap is longer, the application may fail to assign geographical coordinates to some of the photos. In this case, you can increase the time gap in the Max time gap field. Press then the Correlate button to refresh the geographical coordinates. This makes geocorrelation less precise, but you can use the Edit button to adjust the coordinates manually. Once you’re satisfied with the result, press the Apply button to save the assigned coordinates in the photos’ metadata, and you are done.