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What's up, bot? Google tries new Captcha method

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Re: What's up, bot? Google tries new Captcha method

#31

Post by stevenrace »

henning wrote: post #11
amix wrote: post #7

I have implemented something similar called "Visual captcha", where the user has to pick the cat out from 6 randomized Flickr pictures. The code is freely available and should not be hard to integrate into your own projects. Read more on: http://amix.dk/blog/viewEntry/19338

Is that really effective? Just take some face detection code and have it learn what cat fur looks like instead.

There is actually a 'Google Tech Talk' on detecting cats (versus other shapes) from images:

http://www.youtube.com/watch?v=-w72_VwSj6A

  Is it really that easy?  I would think flagging for texture would be difficult, as it's
 likely indistinguishable from noise (data, shadows, clothing..).  Approximating shape/avg.
 contour is likely easier than looking for fur patterns.

  Any suggestions on books/papers/etc on image recognition?

Re: What's up, bot? Google tries new Captcha method

#32

Post by jrp »

rarestnews wrote: post #24
snprbob86 wrote: post #18

Earlier quoted context omitted.

The truth of the whole thing is that Google primarily relies on _behavior_ to detect bots. Captures are just an added layer of defense and serve as a pretty good way of seeding the behavior database. If some user appears to be a bot, serve them a captcha. If they fail, then that behavior was bot-like. Google is using captchas as a way to learn image recognition as well as bot behavior patterns. They know full well th…

Actually I'm really tired of that Google's attempts. The other day I tried to find a something like a .txt file containing all the verbs. I tired searching for "finding resting searching" without quotes, Google kept giving me "find rest search", so I tried quoting it: " "finding" "resting" "searching" ", and adding more and more. Most of those were in anchors, not in text, I added: "allintext:"finding" ..." and here…

http://wiki.answers.com/Q/Is_there_any_text_file_containing_... http://www.apsaulters.net/downloads.html

Re: What's up, bot? Google tries new Captcha method

#33

Post by Hexstream »

omarchowdhury wrote: post #5

A lot of spam operations use humans to solve captchas, so this isn't much of a change for them (actually could make it easier for them).

Yes, however spammers are known to operate on very tight margins (they make a few pennies per million users or something) so even slight additional operating costs can seriously affect their bottom line, possibly sending a profitable operation into the red.

So eventually forcing spammers to employ humans instead of bots is not for naught.

Re: What's up, bot? Google tries new Captcha method

#34

Post by omarchowdhury »

Hexstream wrote: post #33
omarchowdhury wrote: post #5

A lot of spam operations use humans to solve captchas, so this isn't much of a change for them (actually could make it easier for them).

Yes, however spammers are known to operate on very tight margins (they make a few pennies per million users or something) so even slight additional operating costs can seriously affect their bottom line, possibly sending a profitable operation into the red. So eventually forcing spammers to employ humans instead of bots is not for naught.

This is not true.

It depends on what type of spam we're talking about.

The obvious here is social network spam (you don't enter captchas to send emails), which is where captchas are most used against spammers, can be very profitable ($xxx per x,xxx-xx,xxx users).

Re: What's up, bot? Google tries new Captcha method

#35

Post by lacker »

nebula wrote: post #30
rarestnews wrote: post #24

Earlier quoted context omitted.

Actually I'm really tired of that Google's attempts. The other day I tried to find a something like a .txt file containing all the verbs. I tired searching for "finding resting searching" without quotes, Google kept giving me "find rest search", so I tried quoting it: " "finding" "resting" "searching" ", and adding more and more. Most of those were in anchors, not in text, I added: "allintext:"finding" ..." and here…

Dear God, what's wrong with a query like 'allintext:"finding"' ? I got curious and tried just this query, and sure enough Google said that the query looks like an automated one. It means it's not the pattern of the queries that you have sent that triggered this 'you are a bot' response from Google. It's just the one query allintext:"finding". Removing quotes allowed it to be processed. I thought it might have to do w…

Actually when a single word is quoted in a google search it does something - it turns off the matching of words against similar words.

For example if you search for the misspelled [netflixs] you will still get netflix.com, but you can turn that off by quoting the word with the query ["netflixs"]. The plus sign works similarly.

Compare:

http://www.google.com/search?q=netflixs

http://www.google.com/search?&q=%22netflixs%22

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