Those that have seen the moodstream tool at gettyimages.com might have expected that there are better image classification and management tools than what is currently available in Adobe Creative Suite or other commercial or open source graphics programs. Even the Google search by image tool that allows you to upload an image and find similar images is quite impressive, although it is not possible for the users to modify some of the criteria that Google is obviously using to process and match to return the results.
Is there an accepted classification scheme for photos, other than based on their physical qualities (e.g. dimensions, colour/BW, orientation)? I am thinking in terms of metadata such as the colour style, mood, etc?