Aren’t captchas supposed to be human readable?

I have been having increasing problems reading the captchas that now permeate everything we do on the web. I realise they are supposed to be hard for bots to read, but it is rather defeating the point if humans can’t read them either. Here are two particularly impressive specimens from yesterday:

twitter capcha

twitter captcha

In each case my tired old eyes can just about make out what the first word says, but I haven’t a clue what the second word is. Do you? The above might be slightly lower resolutions than the originals, but not much. Try some more.

In any case, captchas don’t seem to work that well. Most can be cracked by image recognition software and those that can’t can always be beaten by crowdsourcing and free porn. I guess the last hope for captchas is that masturbation really does makes you go blind.

12 thoughts on “Aren’t captchas supposed to be human readable?

  1. Karl

    Wanna know a secret? Those are reCAPTCHA’s. The word that you can make out is a computer-generated word. The blurry one is a scan from a random book that the computer couldn’t translate. Since the computer doesn’t even know what the second word is, you can just make it up. Seriously. You could have typed “abated ifuckrabbits” and the computer would have assumed you were human.

  2. Anonymous

    No, I’m pretty sure both are scanned words. It’s just that one is known. And you don’t know which one it is.

    Also, the first one is “Lucia” and the second one is a mis-scan, which is why there is a button to request new words.

  3. Karl

    But you _do_ know which word is “known.” The one that appears clearer is the known word. The computer has an easier time with the clear word, just like the reader. Therefore, the one that is harder to make out must be the unknown word.

  4. Joannes Vermorel

    In my experience, many people need help when it comes to captcha. I have been frequently asked for help by friends or family to “pass” the GMail captcha at registration for example. People give a first try, fails, and then they are not confident enough to keep trying.

  5. Andy Brice Post author

    >The blurry one is a scan from a random book that the computer couldn’t translate.

    Which they then use to translate the word? I was being crowdsourced and I didn’t even realise it? Clever, but sneaky. That would explain a lot if it is true.

  6. Chuck Brooks

    We’ve moved to small Flex surfaces, with an SSL backend connection that requires a POST and an encrypted user-agent heading. The big advantage is that a visitor doesn’t have make another entry, and even better that none of the Flex controls are readable by the ‘bots as yet.
    Chuck Brooks
    FutureWare SCG

  7. RichardM

    Karl is correct – you are being crowdsourced. You can find more details on how reCaptchas work here:

    “Each new word that cannot be read correctly by OCR is given to a user in conjunction with another word for which the answer is already known. The user is then asked to read both words. If they solve the one for which the answer is known, the system assumes their answer is correct for the new one. The system then gives the new image to a number of other people to determine, with higher confidence, whether the original answer was correct.”

  8. Pingback: Chuck Brooks For FutureWare » Blog Archive » Flex A Little To Get Rid Of CAPTCHAs

  9. Chris

    Whatever the reason, or the origin of the examples, it’s an excellent point. How many times a day do all of us use CAPTCHA now? Plenty. Have any viable alternatives been mooted of late? I’ve not seen any.

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