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Check your user is human. Have him retype a word in a graphic Archive captcha technology , you can display a graphic with some text on what's basically a login page, then have your human user type that text back in. It's very difficult indeed for automata to recognise the text, and can be doubly so if you vary the background, change fonts between characters and change text colour, scale, rotation. Mind you, you can make it pretty tough for the human too.Try my demo here Show source code of main demo Show source code of graphic generator
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