6 ms·

A longtime standing solution to hard-to-read captchas are easy to read (but hard to process) captchas. E.g. show a picture of an animal or a shape and ask what

A longtime standing solution to hard-to-read captchas are easy to read (but hard to process) captchas. E.g. show a picture of an animal or a shape and ask what it is, or even just ask a simple math problem or riddle in writing. Problem with those are that they need to be constantly updated from a reliable source, or else, once the solution becomes popular, the spammer can bruteforce it in linear time (no matter how high N is, there are only N possible patterns). This seems to be an attempt at fixing this. Ads are often relatively short lived so by the time the spammer has them bruteforced, it might be out of circulation - and more importantly, there are new ads in. It's an armsrace, and this is a way to pay our troops. Also, it's trivial for advertisers to make many different variations (e.g. one for each sales bulletpoint), so there are many variations in circulation. Since there's often more textual content than the password in the ad, they're not prone to simple OCR, while still easy to comprehend for the user. Obvious shortcomings are if ads are not so shortlived, and if it's easy to identify and break classes of ads (e.g. if it's yellow and has the IE logo in position X, OCR area Y, done). Also, it's a bit of a dealbreaker if I'm forced to open and visit a website to get the password.

olegk 16y ago
You have no idea what you're talking about. > show a picture of an animal or a shape and ask what it is, Ok, so let's say you come up with pictures of 20 different animals. A spam script that picks the same answer every time will have a 5% success rate. > or even just ask a simple math problem or riddle in writing. Computers are way better at solving most math problems than people.
- mseebach 16y ago
  Please read my post. Specifically the second paragraph where exactly this issue is addressed.
  - olegk 16y ago
    Still doesn't make sense. If you display 10 random animals (or shapes), and ask a user to pick the right one, a dumb spam script would have a 10% success rate. If you display one image of an animal and give 10 possible answers, a dumb spam script would have a 10% success rate.
    - mseebach 16y ago
      So if I have a library of 10s of thousands of images of animals, shapes, things etc. that are all easily recognisable to English speakers -- e.g. cat, dog, house, drum, road, tree, book, horse -- and ask them to write in what is it, AND I constantly update that library and retire pictures that's been used many time -- what is your dumb script's success rate? What if I combine three pictures in each challenge - e.g. "cat house triangle"?
      - olegk 16y ago
        My spam script would always answer "cat", so among 8 options (cat, dog, house, drum, road, tree, book, horse), I'd get a 12.5% success rate. Plus you constantly have to update your image library, which a huge pain. Also, recognizing 10,000 images will take me around one day and less than $1000 with Amazon turk, thus giving me a perfect 100% success rate. After that you would have to completely renew your image database.
        mseebach 16y ago
        sigh .. etc. There would be more than 8 options, many more. YES, it would be a pain to update the library, which is why I'm commending this particular concept for solving that problem ...
        StavrosK 16y ago
        You aren't getting it. The probability is 1/<number of options you present to the user>. If you show the user 100 images and ask them to select one, a bot will have a 1% probability to find the right one, but the user will tell you to get lost. If you present 10 images (still a stretch), bots will have 10% success rate just answering randomly. EDIT: Wait, from what I see you mean that the user will have to write "cat" or "dog" or whatever? That's better, yes. Communication, however, is hard, which is why me the GP didn't understand what you meant.
        Ilovepee 16y ago
- raganwald 16y ago
  You have no idea what you're talking about. Please be careful. It could be that his thoughts are excellent but his communication is flawed. It could also be that he has a great deal of general expertise in the subject but is mistaken in this specific statement. Thus, a general statement about him could be false is also aggressively ad hominem. You might want to consider focusing on the statement itself rather than the speaker, such as: "Your suggestion is entirely wrong." JM2C of course, and it is possible that I don't know what I'm talking about. I am not a psychologist or a logician.
pedalpete 16y ago
Your argument is somewhat flawed from a technical level as Olegk mentioned, but also from a business marketing stand-point. Specific ads may be in circulation for a short time, or there may be many running concurrently, but it is the message that the advertiser is trying to get across, the tagline, and it would be of most benefit to the advertiser to get the user to associate their brand with a single concept. Using the example in the article, Subaru may want to be associated with "outback", not "four wheel drive" or "comfy" or "sporty". Businesses who try to target too many things or too wide an audience end up not getting their message across. I'm not saying that what Solve Media is trying to do isn't a great idea. I think it has lots of potential, but they clearly still have more to work on.
shalmanese 16y ago
This was the process used by the Microsoft Research project ASSIRA (http://research.microsoft.com/en-us/um/redmond/projects/asirra/ http://research.microsoft.com/en-us/um/redmond/projects/asir...) which used images of kittens and puppies put up for adoption as a constant fresh source of input data. This was later, awesomely riffed on by HotCaptcha (http://valleywag.gawker.com/246656/a-face-only-a-bot-could-love http://valleywag.gawker.com/246656/a-face-only-a-bot-could-l...) which pulled HotOrNot data and asked you to select the 3 hot women out of 9. Sadly, the site is down now but I remember trying it and it was remarkably useful and a hell of a lot more fun than word captchas.

olegk 16y ago

You have no idea what you're talking about. > show a picture of an animal or a shape and ask what it is, Ok, so let's say you come up with pictures of 20 different animals. A spam script that picks the same answer every time will have a 5% success rate. > or even just ask a simple math problem or riddle in writing. Computers are way better at solving most math problems than people.

mseebach 16y ago
Please read my post. Specifically the second paragraph where exactly this issue is addressed.
- olegk 16y ago
  Still doesn't make sense. If you display 10 random animals (or shapes), and ask a user to pick the right one, a dumb spam script would have a 10% success rate. If you display one image of an animal and give 10 possible answers, a dumb spam script would have a 10% success rate.
  - mseebach 16y ago
    So if I have a library of 10s of thousands of images of animals, shapes, things etc. that are all easily recognisable to English speakers -- e.g. cat, dog, house, drum, road, tree, book, horse -- and ask them to write in what is it, AND I constantly update that library and retire pictures that's been used many time -- what is your dumb script's success rate? What if I combine three pictures in each challenge - e.g. "cat house triangle"?
    - olegk 16y ago
      My spam script would always answer "cat", so among 8 options (cat, dog, house, drum, road, tree, book, horse), I'd get a 12.5% success rate. Plus you constantly have to update your image library, which a huge pain. Also, recognizing 10,000 images will take me around one day and less than $1000 with Amazon turk, thus giving me a perfect 100% success rate. After that you would have to completely renew your image database.
      - mseebach 16y ago
        sigh .. etc. There would be more than 8 options, many more. YES, it would be a pain to update the library, which is why I'm commending this particular concept for solving that problem ...
        StavrosK 16y ago
        You aren't getting it. The probability is 1/<number of options you present to the user>. If you show the user 100 images and ask them to select one, a bot will have a 1% probability to find the right one, but the user will tell you to get lost. If you present 10 images (still a stretch), bots will have 10% success rate just answering randomly. EDIT: Wait, from what I see you mean that the user will have to write "cat" or "dog" or whatever? That's better, yes. Communication, however, is hard, which is why me the GP didn't understand what you meant.
        Ilovepee 16y ago
raganwald 16y ago
You have no idea what you're talking about. Please be careful. It could be that his thoughts are excellent but his communication is flawed. It could also be that he has a great deal of general expertise in the subject but is mistaken in this specific statement. Thus, a general statement about him could be false is also aggressively ad hominem. You might want to consider focusing on the statement itself rather than the speaker, such as: "Your suggestion is entirely wrong." JM2C of course, and it is possible that I don't know what I'm talking about. I am not a psychologist or a logician.

pedalpete 16y ago

Your argument is somewhat flawed from a technical level as Olegk mentioned, but also from a business marketing stand-point. Specific ads may be in circulation for a short time, or there may be many running concurrently, but it is the message that the advertiser is trying to get across, the tagline, and it would be of most benefit to the advertiser to get the user to associate their brand with a single concept. Using the example in the article, Subaru may want to be associated with "outback", not "four wheel drive" or "comfy" or "sporty". Businesses who try to target too many things or too wide an audience end up not getting their message across. I'm not saying that what Solve Media is trying to do isn't a great idea. I think it has lots of potential, but they clearly still have more to work on.

shalmanese 16y ago

This was the process used by the Microsoft Research project ASSIRA (http://research.microsoft.com/en-us/um/redmond/projects/asirra/ http://research.microsoft.com/en-us/um/redmond/projects/asir...) which used images of kittens and puppies put up for adoption as a constant fresh source of input data. This was later, awesomely riffed on by HotCaptcha (http://valleywag.gawker.com/246656/a-face-only-a-bot-could-love http://valleywag.gawker.com/246656/a-face-only-a-bot-could-l...) which pulled HotOrNot data and asked you to select the 3 hot women out of 9. Sadly, the site is down now but I remember trying it and it was remarkably useful and a hell of a lot more fun than word captchas.