It's called  Meta data I believe

It should be used more I think it is hidden within the image not visible but when someone takes an image and opens it in Paint Shop or Photoshop it will be in Image information.

I know you can lock information like this to be read  only and not alterable but I do not remember how.
I think  it might help identify images better because even if the file name has been changed if you kept the original name or creator info locked in to the meta file...that would be recoverable.

Just a thought.