HOW TO differentiate between GIFs & animated GIFs programmatically

"There are 2 kinds of people on the Web - voyeurs and exhibitionists."
Michael Detouzos, MIT

In my Classic ASP days, I managed a portal that was free for all. During this period I understood how important it is to monitor the website continously to stay ahead of smart-alecky visitors who try to attract attention with suggestive usernames or doing something whacky. A common prank that is played is to harass nice folks in the online community by creating a username with a underscore prefixed to some other nice guy's name (the underscore is hardly noticeable if the word is hyperlinked) & misusing his identity. And if a website offers members to upload any files, you can be assured that some vandals will be upto some mischief. All file uploads should ideally be validated & published only after moderation.

Ok, now let me cut to the chase :-). There was a question recently on the ASP.NET Forums that struck a chord. A poster wanted to know whether it was possible to programmatically find if a image being uploaded by the user was a plain GIF or a animated GIF so that he could prevent animated images. After a little searching with my custom search-engine, I found a nice article with C# code to determine if an image contains animation frames.

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