Identicon - Get unique avatar for your website users
Users login in to the Websites, Blogs, Forum and adding their content, comments, asking or answering the questions etc. If user has added his photo then it will get displayed besides his content but not everyone provides his photo image to the sites. Most of the sites used to display a common avatar image for those who have not provided their image. When we read the content, it may be odd to see the same image representation for all users. Identicon comes for the rescue.
Few sites use the services from Gravatar, which could display the photo image using their email address or ip address but again if the photo image is not added, it will give a common avatar image. If you visit Stackoverflow, you might notice the unique image for every user. How this is possible? The answer is Identicon.
Identicon generates a unique image for the User using their hash value of their connecting IP address. Don Park created this idea and he also implemented in Java.
Wikipedia description of Identicon.
An Identicon is a visual representation of a hash value, usually of the IP address, serving to identify a user of a computer system. The Identicon graphic is relatively unique since it's based on the user's IP, but it is not possible to recover the IP by looking at the Identicon.
There are open source libraries available in Java
to generate identicons.
Identicons gives unique image for the user but still keeps them anonymous.