ios-same image detection?
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I am making a basic app that uses Flickr's API. If the image requested doesn't exist Flickr returns with this image: http://l.yimg.com/g/images/photo_unavailable.gif 

I would like my program to detect that Flickr has returned this image instead of the one requested. Is there any way I can include this image in my project then check it against the photo returned? If not are there any other ways of detecting that Flickr returned this image instead of the one requested?

Thanks for the help!

Shredder