Visual and OCR-Based Features for Detecting Image Spam

The presence of unsolicited bulk emails, commonly known as spam, can seriously compromise normal user activities, forcing them to navigate through mailboxes to find the - relatively few - interesting emails. Even if a quite huge variety of spam filters has been developed until now, this problem is far to be resolved since spammers continuously modify their malicious techniques in order to bypass filters. In particular, in the last years spammers have begun vehiculating unsolicited commercial messages by means of images attached to emails whose textual part appears perfectly legitimate.