Get the URL of a HotLinked image

[eluser]webthink[/eluser]
You have a controller which is responsible for file-reading the images and then serves the image data via the header correct? and presumably you have links on other pages which point to that page. If I understand you correctly you're interested in knowing which links are being clicked to access you image serving script. So in the image serving controller you check HTTP_REFERER and if it's set you have the referring page to do what you want with. If it isn't you know that an attempt was made to access the page directly.

Perhaps a better description of your requirements would help.