title: javascript/jquery check whether an image exists?
body: <p>Given an image url below
  <a href="http://www.bikewalls.com/pictures/abc.jpg" rel="nofollow">http://www.bikewalls.com/pictures/abc.jpg</a> (does not load)</p>
  
  <p>I need a javascript/jquery function/code to alert saying the above url is valid or not.These urls will be passed as parameters. Taking the case of above example will be very helpful.</p>