pictool is a command line program for manipulating and altering images. It's mostly useful for image metadata manipulation. Here's the currently available commands:

$ pictool  -h
usage: pictool [-h]
               {md-tag-list,image-region-add,image-region-remove,gps-set,gps-get,location-set,face- normalize,gps-get-from-query} ...

Working with images and image metadata

optional arguments:
  -h, --help            show this help message and exit

sub-command help:
  {md-tag-list,image-region-add,image-region-remove,gps-set,gps-get,location-set,face-normalize,gps-get-from-query}
    md-tag-list         List all metadata tags for the given picture(s)
    image-region-add    Add image metadata region to the given picture(s)
    image-region-remove
                        Remove image metadata region
    gps-set             Modify GPS data for the given picture(s). This does not set the GPS data if the picture(s) already contains GPS data.
    gps-get             Show GPS location
    location-set        Set location info based on the available GPS data for the given picture(s). This sets tags like Iptc.Application2.CountryCode
    face-normalize      Normalize faces from images and store results in new images
    gps-get-from-query  Get the GPS coords from a given (address) query. This command does *not* use any picture(s). It is just a helper.It uses the nominatim service from openstreetmap

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