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Breaking captcha is bad, mkay :)
If you're using a CAPTCHA, you're doing it wrong already.
What's the replacement? Tying every account to a mobile phone or credit card?
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If you're using a CAPTCHA, you're doing it wrong already.
Yeah, all these CAPTCHA stories are definitely making me think there's no refuge left of simple tasks humans can do that machines can't. What's the replacement? Tying every account to a mobile phone or credit card?
That's a stupid idea, based on some weird assumption that it's somehow safe to give access to your system for a user, but not for a robot. If the only thing stopping people from messing your system is automation, you should rethink it from the get go.
For those interested, the minteye captcha has been broken by other methods as well. Speech recognition: https://gist.github.com/4520930 Laplace: https://gist.github.com/4564489 Fourier transform: http://nbviewer.ipython.org/urls/raw.github.com/rjw57/mintey...
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It's totally sarcasm
Not sure it's sarcasm, more like some blackhat SEO who wants to exploit it.
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Yeah, all these CAPTCHA stories are definitely making me think there's no refuge left of simple tasks humans can do that machines can't. What's the replacement? Tying every account to a mobile phone or credit card?
The thing is, CAPTCHAs are used to validate it's a human operating the interface, not a robot. That's a stupid idea, based on some weird assumption that it's somehow safe to give access to your system for a user, but not for a robot. If the only thing stopping people from messing your system is automation, you should rethink it from the get go.
Nice point.
> If the only thing stopping people from messing your system is automation, you should rethink it from the get go.
Are there systems that can't be abused through automation, or where that's much less of a concern? (Serious question, not intended as snark.)
Maybe throttling activity is a better approach... it's volume that is harmful to the system, not interactions with programs per se.
Don't know how you throttle spammers distributing activity across a number of accounts and IP addresses though...
Hhahahaha, comment on the blog "Please post the Visual Basic codes for this. The language you post in the article is not Visual Basic. Thank you." xD God !
It really makes me wish for some kind of federated comments system or unique username so I can go out and find more of his work!
Hhahahaha, comment on the blog "Please post the Visual Basic codes for this. The language you post in the article is not Visual Basic. Thank you." xD God !
If it is sarcasm this guy nailed it. Looks like half my inbox.
For those interested, the minteye captcha has been broken by other methods as well. Speech recognition: https://gist.github.com/4520930 Laplace: https://gist.github.com/4564489 Fourier transform: http://nbviewer.ipython.org/urls/raw.github.com/rjw57/mintey...
Could someone explain the general idea behind using FFT in these situations (excusing my ignorance)? I recall it from my university days but that was completely out of context. I know you can use it to decompose audio signals into frequency components, I don't understand how it applies to images though.
Sharp edges in an image have high frequency components, just like a sharp transition in an audio signal. Filtering the high frequencies will blur the image, while filtering low frequencies will enhance edges.
This is very oversimplified, but will hopefully give you a bit of an idea. I encourage people to learn more about Fourier theory, because it explains a lot.
One introductory page that you may find useful is: http://cns-alumni.bu.edu/~slehar/fourier/fourier.html
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Could someone explain the general idea behind using FFT in these situations (excusing my ignorance)? I recall it from my university days but that was completely out of context. I know you can use it to decompose audio signals into frequency components, I don't understand how it applies to images though.
The basic idea is that just as an audio signal can be decomposed into frequency components, an image can be decomposed into frequency components, but in two dimensions. (Imagine stripes of varying frequency and direction instead of sine waves of various frequencies.) Sharp edges in an image have high frequency components, just like a sharp transition in an audio signal. Filtering the high frequencies will blur the im…