Current Captchas are based on distorted alphanumeric characters (text based Captcha) displayed to user before registration to all kind of online platforms such as forums, blogs and sharing knowledge websites like wikipedia or Yahoo! Answers. After the user has deciphered the Captcha, he may continue to contribute a comment or any other action he is interested in.
Unfortunately, automated hackers become more and more sophisticated these days, but the more they become sophisticated – the more Captcha becomes difficult. Consequently, more human users give up login to sites with difficult Captchas, not to mention disabled users with cognitive problems such as dyslexia, or physical disabilities such as blind persons – they are denied access to Captcha right from the beginning!
Image based Captcha is the latest alternative to current text based Captcha. It’s based on a set of images easier to be recognized and classified by human users than traditional textual Captcha, yet at the same time, much more difficult for robot hackers.
How does it work?
Very easy. It only takes a few steps to be solved. First, a set of images with letters above are displayed. The user is being required to identify and click on a sequence of images. After he completes correctly the test and is verified as a human – he is allowed to carry on his online session. It’s easy, funny, not boring as a text based Captcha.
VidooCAPTCHA is an example to an image based Captcha.
Click here to read about 3D images captcha.
