Imagefield additional attributes

I have a feature on a site I’m working on where it would be easiest to add an extra field attribute (along with alt and title) to the image field. Ideally a select list with a few different options (think categories for the uploaded image). Doing this goes beyond the scope of what I’m *used* to doing within Drupal.

Can you point me in the right direction on where to look in order to accomplish this, or if you’re familiar with a pre-existing module that might already accomplish this, that would be awesome as well!

Thanks in advance

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