Asirra (Animal Species Image Recognition for Restricting Access) is a new HIP (Human Interactive Proof) test released by Microsoft Research. It asks users to identify pictures of cats and dogs, as opposed to numbers and letters that the familiar CAPTCHA (Completely Automated Public Turing test to tell Computers and Humans Apart) systems use. HIP is in essence a challenge to say are you a human or a machine?
CAPTCH can be somewhat difficult for people to navigate correctly. The “tougher” you make the image, i.e. more resistant to automation and attack, the harder it is for humans to use. I use it on this blog to help prevent comment “robots” that would fill my blog with advertising and other unwanted content.
There has been a lot of pro and con talk about CAPTCHA in the development and user communities, but the simple truth is that other than CAPTCHA there has not been a really good alternative… until now!
The premise of Asirra is to display several pictures and ask the user to identify the species of the animals shown. The approach is not unique, other attempts have been seen, but they have all suffered from a common weakness, namely a relatively small database of images to draw from.
Asirra uses the Petfinder.com database which contains @ 3 million images. So this should not be an issue, at least for awhile!
Check out the web site, the system is free, and there is example code and connection info available. I am going to take a look at implementing it on my own blog.
Cheers,
Robert Porter