How can I add extra data to a file field? I am using Drupal 7's core module, file.

The file field array looks like this:

[field_game] =&gt; Array
    (
        [und] =&gt; Array
            (
                [0] =&gt; Array
                    (
                        [fid] =&gt; 57
                        [display] =&gt; 1
                        [description] =&gt; the-pyro-guy.swf
                        [uid] =&gt; 0
                        [filename] =&gt; the-pyro-guy.swf
                        [uri] =&gt; public://swf/the-pyro-guy_2.swf
                        [filemime] =&gt; application/x-shockwave-flash
                        [filesize] =&gt; 5506729
                        [status] =&gt; 1
                        [timestamp] =&gt; 1346017444
                        [rdf_mapping] =&gt; Array
                            (
                            )
                    )
            )
    )


In addition to the above data, I want to store keys containing the game's height and width in this same file field. Can I do this, preferably in code?
You can't by default, but check out the File Entity module.


  This module extends the core file entity, making it a full fledged
  entity, allowing for fields, display formatters, and more.


This allows you to add fields (such as a height/width field) to files in the same way that you add fields any other fieldable entity (nodes, terms etc...).