A study on e-mail image spam filtering techniques

Spam filters are the most used software tool used by businesses and individual to block spam mails entering into their mail boxes. Until recently, majority of research effort was expended on controlling text-based spam emails. However, the past few years have envisaged a novel approach, where the spammers embed the text message into an image. Thus, the anti-spam filtering research is forced to move from text-based techniques to image-based techniques. Spam and the spam blockers designed to combat it have spawned an upsurge in creativity and innovation. Many software developers are developing new and every more effective spam filtering software. All the methods have a common dream that is to eliminate 100% of the spam, which is still not a reality. To reduce the gap between this reality and dream, researchers have proposed many different types of spam filters and this paper provides a review of them.