AS3 URLRequest XSS?

Question

Im basically working on an image analyser that downloads images from another server. I have no control over the server but I only want to scan images not html pages.

would something like this work?

new URLRequest('http://otherserver.com/someimage.jpg');

Or would I have to use a PHP script to act as a proxy for my script and have the swf look up that php script with parameters instead?

new URLRequest('http://myserver.com/proxy.php?image=someimage.jpg');

I only ask because I remembered AJAX requests wont work cross domain so I wondered if the same thing affects AS3 aswell.