If you have not read our previous article on reading smartphone text messages, then go ahead and read that first before continuing to read this article. Researchers at Stanford University have come up with a technique that can decipher text-based CAPTCHA used by many websites.
CAPTCHA was developed to tell the difference between computers and human interaction. Most people have seen or used CAPTCHA when trying to register or set up a new online account or even to leave a comment on a blog. I find them irritating and don’t use them on any of my websites. They can be an effective tool, but I just think they turn off readers or customers. They are primarily used to block spambots that automate the process of setting up an account or for leaving comments on a website or blog.
The Stanford researchers have developed methods where the backgrounds on CAPTCHA, that make it really hard to read the letters, are cleaned up to make it easier for an automated system to read the text. Also, the researchers developed methods that break the text string into individual letters allowing easier viewing. They developed a program to do this called Decaptcha.
Surprisingly, Decaptcha was successful as high as 70 percent of the time on the websites they tested it against. The only site where it was not successful was Google. Google uses reCAPTCHA which they bought from Carnegie Mellon a few years back.
If you already have a Google Account, you can get reCAPTCHA by going to the reCAPTCHA and signing up. Also, if you have a WordPress website, you can use the reCAPTCHA plugin. The one downside of the WordPress plugin is that is has had no updates since April of 2011 and states that it is only good up to WordPress 2.9.2. Some of the users of the plugin,however, do state that it works on the current version of WordPress, version 3.2.1.
If you use CAPTCHA on your website, you may want to look at monitoring its use and see if spam bots are beating the system. If so, look at switching to a more effective version of it such as reCAPTCHA.
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