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Google's Street View computer vision can beat reCAPTCHA with 99% accuracy

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Re: Google's Street View computer vision can beat reCAPTCHA with 99% accuracy

#141

Post by [deleted] »

willvarfar wrote: post #131
slacka wrote: post #121

Earlier quoted context omitted.

Like Deep Blue, Watson represented a major advance in the state of weak AI. However at its core, it's still just a text-based statistical search engine. It has no ability to "learn" new abilities. Its algorithms will use previous answers to adjust ranking of answers, but once a category is finished, that data is lost. For new data, its database needs to be re-indexed. For new behavior like recognizing pictures or pla…

Yes its interesting; you can easily imagine that the following trends are detected: * "home and safe" "safe as houses" etc * "safe in bed" "safely tucked up in bed" etc * "volcano" ... no clear data. Certainly dangerous being a volcanologist, but that'd be great AI googlefu * "pensioner attacked in park" .. "our parks are not safe" etc... Hmm, Parks are the most dangerous. Because frequency of local newspaper reports…

[deleted]

Re: Google's Street View computer vision can beat reCAPTCHA with 99% accuracy

#142

Post by msvan »

Here's a captcha idea: make people write a 100-word essay on a specific topic. If it's good, you're accepted and you won't have to do it again. If it's bad, you're either a computer or cheap Nigerian labor. When we get to the point where we can't distinguish a computer from a human, we'll just let them be a part of the community.

Re: Google's Street View computer vision can beat reCAPTCHA with 99% accuracy

#143

Post by schrodinger »

PeterisP wrote: post #75
Lambdanaut wrote: post #60

Earlier quoted context omitted.

The suggestion to "go to a physical location to get a trusted government signature" has deeper flaws as well. What's to stop a bot writer from getting a signature and plugging it into his bot?

1. Unlike e-mail accounts or such, a botwriter wouldn't be able to get thousands of such signatures to go on as soon as the first one is identified and blocked; if he puts his own key in the bot - bam, you (and everyone else you know) can exclude him from your services permanently, and he wouldn't be able to come back with a fresh account unlinked to that one, ever. 2. The signature is linked to a specific person, so…

If multiple signatures from the same key are recognizably the same person, wouldn't this have the unfortunate implication that your identity can be linked across different services? There'd be no way to have multiple email addresses anonymously without being able to trust the provider.

Re: Google's Street View computer vision can beat reCAPTCHA with 99% accuracy

#144

Post by vfclists »

Google are getting too creepy for any sensible persons liking. Addresses which are off the street in apartment complexes are now getting recognized as well.

Whenever I see these kind of captchas I switch to audio captchas. It is rather unethical for Google to use recaptchas in this way.

Re: Google's Street View computer vision can beat reCAPTCHA with 99% accuracy

#145

Post by michaelt »

BoppreH wrote: post #122
zwegner wrote: post #45

This particular issue (AI performance on captchas) is really quite fascinating. It's an arms race, but the problem is, only one side can win. Google is claiming they have improved their system in some (understandably) unspecified way, but there's only so far this can go. Captchas need to detect whether someone is human, but it has to work for everyone, ideally, even those with disabilities. Any simple task a human ca…

All captchas I have seen were used to stop spam. The problem with spam is that 1) it's noise and 2) appears in large amounts. Captchas approach the problem 1), by assuring only people can post and then hopefully increase the signal quality. It sucks because it requires mental effort, is hard on people with disabilities, blocks potentially useful bots (see reddit bots) and leads to an arms race. What if we tried to so…

Isn't most spamming done by botnets these days, to avoid IP bans? So they have a plentiful supply of CPU cycles?

Also, regular users who visited your site without wouldn't install any software, so they'd be running the proof-of-work as slow javascript, while spammers could use GPU or even ASIC acceleration if proof-of-work became widespread.

Re: Google's Street View computer vision can beat reCAPTCHA with 99% accuracy

#146

Post by Theodores »

zwegner wrote: post #45

This particular issue (AI performance on captchas) is really quite fascinating. It's an arms race, but the problem is, only one side can win. Google is claiming they have improved their system in some (understandably) unspecified way, but there's only so far this can go. Captchas need to detect whether someone is human, but it has to work for everyone, ideally, even those with disabilities. Any simple task a human ca…

> The street address/book scan approach that Google uses is interesting in that the exact solution is not known, so they presumably have to be somewhat forgiving in accepting answers (as their machine learning might have gotten it wrong).

In the original captcha algorithm there are two images shown, one where the answer is known and one where the answer is not known. The unknown - the street sign or that extract from an old newspaper - is guessed at by those filling in the captcha.

If 90 people say it looks like '11' and 5 people say it looks like '71' and another 5 say it looks like '77' then you can be 90% certain that it is '11'. The machine has therefore 'learned' what that number is, it is '11'. This can continue being used in the captcha however, now that it is known, people will have to type '11' for it.

That is how it fundamentally works and why the two snippets of information 'to get right'. You can try it for yourself, get the first one of the street sign deliberately wrong and see if it lets you through.

Re: Google's Street View computer vision can beat reCAPTCHA with 99% accuracy

#148

Post by epi8 »

msvan wrote: post #142

Here's a captcha idea: make people write a 100-word essay on a specific topic. If it's good, you're accepted and you won't have to do it again. If it's bad, you're either a computer or cheap Nigerian labor. When we get to the point where we can't distinguish a computer from a human, we'll just let them be a part of the community.

Who judges if the essay is good?
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