Format your data
First you need a file formatted with the same headings and information as the following table. It should then be saved as a comma-separated-value file.
It's important to make sure your latitude and longitude have eight decimal places of precision, to ensure that your geotagged photos can be accurately located.
There must be a column named "SourceFile" in the CSV which includes the names of the images including their file extension.
If your file names don't include the file extension, you can add it using a program like excel:
- With your file names in column A, insert two extra columns next to column A with the original file names.
- In the new column B, enter ".JPG" if the file extension is JPG.
- In the new column C, enter "=CONCAT(A1, A2)".
- Copy column C
- "Paste Special" into column C selecting the text only option. This should replace the formulas in column C with the concatenated text.
- Rename column C "SourceFile"
- Delete the original column A and column B.
- Save the file as a CSV
The other columns must have the same names as columns in the example below, to match the command line arguments required by the conversion software. These column names correspond to valid EXIF header tags. The conversion software reads the column names and matches them to a valid EXIF header tag.
Download the conversion software
The conversion software to use is exiftool. You can download it from http://www.sno.phy.queensu.ca/~phil/exiftool/.
Run the command line program
Once downloaded, the command line argument to run is:
exiftool -GPSLatitude -GPSLongitude -GPSAltitude -GPSLatitudeRef -GPSLongitudeRef -GPSAltitudeRef -csv="path-to-the-csv.csv" -o output/ path-to-images/
Each -GPS* flag tells exiftool to read a column by the same name from the CSV file and add that information to the exif data of each photo.
The "-o geotag_output" flag and argument create a new directory called "geotag_output" and puts all the newly geotagged photos inside that new directory, preserving your original photographs.
If you run simply exiftool you will see the help text for the program.