Is it possible to tell the type of image just from a remote path?

I'm working on what is effectively a watermarking system, where the user has a URL something like this.

http://ift.tt/1PR8eEH

I'm wondering if the users image_path is something like http://ift.tt/1zjDCkJ, there's no extension in the url, so I can't tell what type of file the image is.

Is there anyway I can get what the file type is just from a remote path?