Quick-and-Dirty Geotagging with a Bash Script

Dmitri Popov

Productivity Sauce

Mar 22, 2016 GMT
Dmitri Popov

When you need to quickly geotag a bunch of photos with an approximate location (e.g., city and country), a simple Bash shell script can help you to do it much faster than a heavy-weight application like digiKam. The script uses the Nominatim service to perform forward geocoding (i.e., obtain the geographical coordinates of a given place name) and a combination of curl, jq and tr tools to extract the latitude and longitude values. It then uses the ExifTool to write the obtained coordinates to all JPEG files in the current directory. To install jq and ExifTool on Debian and Ubuntu-based distributions, run the apt-get install curl jq libimage-exiftool-perl command as root.

To deploy the script, copy and paste the code below into a new text file and save it under the geotag name.

lat=$(curl "http://nominatim.openstreetmap.org/search?city=$1&country=$2&format=json" | jq '.[0] | .lat' | tr -d '"')
lon=$(curl "http://nominatim.openstreetmap.org/search?city=$1&country=$2&format=json" | jq '.[0] | .lon' | tr -d '"')
exiftool -GPSLongitude=$lon -GPSLatitude=$lat -ext jpg .

Copy the script to the /usr/sbin directory, and change the script's permissions to make it executable:

sudo cp geotag /usr/local/bin/
sudo chown root:root /usr/local/bin/geotag
sudo chmod 755 /usr/local/bin/geotag

To geotag photos using the script, run the geotag command followed by the desired city and country, for example: geotag tokyo japan

Here is how the script works. The curl tool uses a HTTP request to fetch geographical data for the specified city in the JSON format. Sometimes this request returns an array of places that match the specified criteria. In most cases, the first item in the array is the relevant one. So when the JSON output is piped to the jq command, it extracts the latitude and longitude values from the first item in the array. The tr tool then strips quotes around the latitude and longitude values, and the ExifTool writes them into all JPEG photos in the current directory.

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