Pictcha is an experiment designed to improve security over typical text-based CAPTCHAs and enhance image search.
CAPTCHA is an acronym for completely automated public turing test to tell computers and people apart. It ensures that an online transaction is being performed by a human rather than a computer.
CAPTCHAs have been successfully used to distinguish people from computers by challenging users to decipher distorted text, a task that is relative easy for people but quite difficult for computers.
However, with the improvement of machine-learning algorithms, CAPTCHAs must be regularly updated to thwart would-be spammers.
In the Pictcha experiment, we show users a randomly selected Web image and challenge them to provide two descriptive labels.
Passing the test requires that at least one of the user-provided labels matches a known tag for the image. The collection of known tags is generated by previous users who have tagged the same image.
Pictcha was created by the Economics and Social Systems group.
Try it is not working . Is it really working for any one ?Comment by Hari K T (July 6, 2009, 2:52 am)
"Try It" button not taking anywhere.Comment by Rajbir Singh Jawanda (July 13, 2009, 2:18 pm)
how is accessibility addressed within the Pictcha Project concerning blind and visually impaired Internet users? Thank you.Comment by Solona (July 18, 2009, 10:47 am)
What plans does Yahoo! have in place to ensure that web sites protected by PICTCHA are accessible to blind and visually impaired users?Comment by Darrell Shandrow (July 18, 2009, 12:54 pm)
Hey! I liked the concept. Should be used very helpful for photo sharing/social networking websites. However, what about users who work in text only (low end PCs) environment.Comment by Aman (July 22, 2009, 10:00 am)
Hi. My name is Rob Bendtzen. I am a totally blind person who has found it very difficult to use Captcha sites suchas Yahoo. The reason is simply because the letters/numbers displayed on the screen are invisible to me as a blind person. I would always have to have sighted assistance. Quite often, when I do enter the captcha, it's not the right one I have to get another set of characters to enter. At any rate, if you are thinking about replacing Captcha with Pictcha, may I suggest making it accessible for disabled people? Please let me know. Thank you very much. Rob BendtzenComment by Rob Bendtzen (July 26, 2009, 6:40 pm)