Extractor is a simple Ruby binding for libextractor. It allows you to read metadata from a wide number of file types. You may install it by typing
gem install extractor
or by downloading it manually here.
To use extractor try something like this:
require 'extractor'
metadata = Extractor.extract('happy.mp3')
puts metadata['mimetype']
puts metadata['artist']
Sometimes there will be more than one entry for a metadata type. For example, an mp3 may have two artists. If this is the case then you might have
metadata['artist'] == ['Puff Daddy', 'The Family']