Damn! There goes my one patentable idea I've had since working at Go Daddy. I wasn't going to have any noise and basically make it look like a static image. But the idea is now decimated by prior art.
My implementation was going to be better because my plan was to fragment the CAPTCHA text randomly. Each piece would then be a separate frame in the animated GIF with a minimal delay between frames. To the human eye, it would look like a fixed image and would be incredibly easy to recognize. To the automated CAPTCHA bot, the interpolation required would make defeat not worthwhile. As bots became more sophisticated, tweaks could be done to add randomness to the slicing or noise elements.
I realize, of course, that I could still make this and release it as open-source but my motivation's been sapped. Lazy Web, enjoy.
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