exiftool

 exiftool  is THE most comprehensive image EXIF (and other metadata) extraction utility. It's written in Perl and works as a regular, *nix command line tool.

Usage examples
extracting common values in JSON format:

The # at the end of GPSLongitude and GPSLatitude will force it to return the decimal format (eg. 53.115584 instead of 53 deg 6' 56.10" N).