How to determine if a given URL link is a video or image?

Question

I\'m trying to take a given URL entered by user and determine if the URL is pointing to a image or a video.

Example use case:

When a user paste in the URL o

Answer 1

Hit the link and inspect the content type header? If the result is a HTML page you could look for the largest image or embedded flash file on the page and choose to display that?