Video CAPTCHAs target cyberbaddies NuCaptcha has extended its video-based CAPTCHA service that it claims will make things easier for users while making life more difficult for spammers and other cyber-baddies. The technology, which is customisable, involves asking users to identify moving text in an animation against a video background. NuCaptcha is positioned …
Looking at their demo, if you consider that a video is basically just lots of frames then each frame looks easier to solve than most typical CAPTCHAs, and if you can't identify the text try again with the next frame which helpfully gives you the same letters but a slightly different arrangement so your OCR should have better luck!
The only reason I suspect a system like this might work is security by obscurity, if any major sites start using it then I expect it to be added to automated tools in no time, with a far higher solving success rate than most existing CAPTCHAs
On the other hand I was able to read it, which does put it one better than most of the things - have you tried solving googles account signup one? (they have the best system with recaptcha, which they don't use themselves for their own services?? and don't even get me started on the "visually impaired" version!)
This looks to be easier for computers to interpret.
Automated CAPTCHA interpreters attempt to separate the words/letters from the background and interpret them. With the current static CAPTCHA they only get one image to work with.
With an animated CAPTCHA they can interpret each individual frame and come up with an "average" interpretation which will be more accurate than a single frame. Additionally, since it is an animation, the images can be interpreted as a sequence and the different animation elements separated and interpreted.
Overall, animating the CAPTCHA will provide to much extra information for the automated interpreters.
Why not just isolate the video clip background? It should be the /exact same/ each time, unless it too is randomized (such as the bubbles example).
Either way, the high contrast and wildly different colors vs the background should make any program that is intelligent enough to pull individual frames out of the animation easily able to figure out the characters.
http://www.nucaptcha.com/resources/security-features
"We're often asked how NuCaptcha is displayed. One common assumption is that it is rendered in Adobe Flash. NuCaptcha is displayed as an H.264 MPEG-4 Video Stream that is rendered in your browser in a variety of ways."
It uses Flash in my Firefox 5 and Chrome 12. Presumably that's because I have Flash plugins installed. Didn't Google announce they were ending support for native H.264?
Natural language and/or maths CAPTCHAs work for me.
We need to just work out an alternative to captcha's full stop, not just 'improve' them. They are horrible things. Pretty much every time I come across one these days I sit here reload the damn thing until I can get one I can actually read.
I concur with the above about Google's Account captcha's too, I sadly work with a lot of these.
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