Regex to get a filename from a url

I am trying to write a regex to get the filename from a url if it exists.

This is what I have so far:

(?:[^/][\d\w\.]+)+$

So from the url http://www.foo.com/bar/baz/filename.jpg, I should match filename.jpg

Unfortunately, I match anything after the last /.

How can I tighten it up so it only grabs it if it looks like a filename?