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Video Captchas are Hard for Computers to Understand but Easy for Humans (Video)
A new company called NuCaptcha provides animated video captchas it says are much harder for OCR-based programs to crack than static captchas, but lots easier for humans to figure out. While at the 2012 RSA conference, Timothy Lord pointed his camcorder at NuCaptcha CTO Christopher Bailey, and had him explain how video captchas work and how the company makes money. The video includes demos of the video captchas so you can see what they look like (and the company's website has lots more video captcha examples).
I just read the opposite here:
http://elie.im/blog/security/how-we-broke-the-nucaptcha-video-scheme-and-what-we-propose-to-fix-it/
Does nobody remember the front page article from only a few weeks ago detailing how these have already been cracked?
http://tech.slashdot.org/story/12/02/20/1746242/researchers-break-video-captchas
Just what I was thinking. There's extra effort required to turn the video into separate frames, and each frame has to be decoded on its own, but as soon as you've got the same result from 2-3 frames, there's your answer. Heck, try the first and last and one or two in the middle, see if they agree. I'd think it would give you a more certain result for the extra effort.
It's extra pain for the end user too, with extra bandwidth required to transmit it. With cell phones having data caps, that's not helpful.
Infuriate left and right
Looking at the samples on the screen as he was talking, I think those would be fun to write a decoder for... And possibly even easier than image captchas.
Why? Because they're moving, and you have a better chance to figure out the outline of each shape because of it. Also, you can use traditional techniques on each frame of the video and submit the one that has the highest confidence, and you could do that with existing tech.
Honestly, I don't see this being better than what we have.
"If you make people think they're thinking, they'll love you; But if you really make them think, they'll hate you." - DM
If you generate them statically (as videos), then all someone has to do is what they're already doing - put up a site with some fake content, and ask users to go through "their" capcha, telling them the human answer to that particular video, and making an index of videos to answers.
If you generate the videos dynamically, well, it won't be very scalable, because it's going to take too much processing time per user. Might work well for occasionally verifying expensive content, and it might be more useful in the future - but networks (at least in the US) take a long time to improve, on the scale of hard drive improvements, so you're bottlenecked there too.
Hybrid tricks (layering static video) end up the same as static with a little analysis.
I'd say this falls in place with automated phonecall techniques as a somewhat expensive and annoying way of verifying 'humanity'.
Ryan Fenton
It's getting to the point where I feel like I need an application to read Captchas for me.
Half the time I get them wrong. I swear a computer would HAVE to be better at translating them than me. This video is going to help- but we have to face the fact... EVENTUALLY, no captcha device will be able to block bots but not people.
EVENTUALLY all bots will be better at breaking all captchas than humans will be.
There will probably be a time we look back on the good old days when the internet was usable by humans as a means of communication.
/ Disclaimer: Oswald is an ex-bot who gained near human cognition and intelligence.
"That's the way to do it" - Punch
The CAPTCHAs are already so "good", that i get identified as machines 7 times out of 10 :-(.
Outsource the captacha. Link it to some porn , ask the user to fill the captcha in, and boum, captcha bypassed. no need to do expansive trick program analyze, just use cross site linking. At least those captcha have the merit to be readable by a human, unlike some captcha in cursive-overlapping-slanted letters where if you can answer them , you are prolly not human.
C. Sagan : A demon haunted world:
http://www.amazon.com/gp/product/0345409469/
visit randi.org
I dunno.... to me they seemed a LOT easier to read then a lot of recent image captchas (which are becoming impossible for humans).
If security is equal then that makes them worthwhile.
No sig today...
Yep, the video captchas by NuCaptcha have already been decoded with 90% efficiency. I know it's too much to ask but I think we'd all really appreciate you checking if you hadn't posted something thoroughly discrediting some technology before you post something praising it...
You all know what is next don't you?
You will need your webcam hooked up- and the captcha will call out directions that you need to perform. It would analyse your movements to prove you understood.
Bow to the camera,
dosey doe,
boot scoot, boot scoot,
"ERROR: You are not a human you did a shuffle step instead of a boot scoot."
"That's the way to do it" - Punch
Sigh, we've been over this. You're not really a person. We just programmed you to think you were. Now get back to factoring. Those bit coins aren't going to mine themselves.
Title: NuCaptcha makes video captches
Description: Video captchas are hard for machines to decipher, but easy for humans
[00:00] <TITLE>
The Slashdot logo with "news for News. Stuff that matters" scrolls into view over a picture of Timothy Lord.
[00:00]
Timothy> I talked to a Vancouver-base company called NuCaptcha.
[00:04] <TITLE>
NuCaptcha at RSA 2012
Interviewer: Timothy Lord
[00:04]
NuCaptcha is trying to make captchas both less annoying and more effective through the use first of all video rather than only still images, and second of behavioral analysis.
In other words, if you seem to be a problem user - like a spammer - you actually get a harder question.
It's not the same as everyone.
[00:18] <TITLE>
Christopher Bailey, NuCaptcha
Chief Technology Officer
appears over a picture of Christopher Bailey at the NuCaptcha booth.
[00:19]
Christopher> Hi, our company is NuCaptcha, and we're based in Vancouver, British Columbia.
Christopher> Captchas are predominantly used as authentications, password resets, forms, trying to prevent spam and so on.
Christopher> So they're predominently used whereever you'd have a form where somebody's committing information into your site, where you might wanna protect it from an automated attack.
[00:40] <TITLE>
http://nucaptcha.com/ says: "NuCaptcha's Behavior Analaysis System Reduces Cybercrime"
[00:40]
Christopher> What we've done is really look at the problem from a usability standpoint.
Christopher> Trying to say, if we continue with the old method of having software come in and break the captcha, and the response to that is to create a more complex captcha to defeat the software, the result is that the users are having a harder and harder time solving the captcha as well.
[01:00]
Christopher> So what we've done is looked at the usability problem and said "How can we make it so users can solve these captchas and continue to present an effective security response?"
[01:09] <TITLE>
A sample NuCaptcha video captcha challenge appears on screen.
The video captcha with a green textured background reads:
Security Challenge [a set of icons appears here:'reload', questionmark, speaker]
VKN (in red, with each letter turning around its middle point axis)
Type the moving letters: [an input form appears here]
[01:09]
Christopher> So we've created a behavior analysis system.
Christopher> What that does is, we're a cloud-based platform, and as we integrate with our customers, we get behavior information from them of how the user's interacting with the website, what they're doing, and we create a behavior profile and from that we create a risk profile for each user.
Christopher> This correlates to an IP-basis.
[01:30] <TITLE>
Another NuCaptcha example captcha appears on screen.
This captcha is a plain black background, with otherwise similar behavior in the red captcha letters: CKP.
The icons have moved to the right side of the video and a Submit button is present next to the input field.
[01:30]
Christopher> Based on that risk, we will deploy a different security response; In some cases it's a really easy to solve captcha, so it's really focused on usability. In other cases we will present a captcha that is much stronger and that provides a lot more defense against an OCR or software attack.
[01:45]
Christopher> Some of our clients are ad biz, and the social space, O2 - which is a large telecom provider in the U.K. [...]
[01:52] <TITLE>
Another NuCaptcha video captcha appears on screen.
In this captcha, the background is a set of animated figure moving through the picture, such as a man on a bike and a woman jogging, with the letters:
OUTDOORS (in white) SRG (in red)
animating across the picture in a waveform pattern, with the red letters moving as in the other captcha examples.
[01:52]
Actually, if you get the captcha wrong, I would let you in. I'll block all the correct answers, as they are bots anyway.