My face is mine: fighting unpermitted tagging on personal/group photos in social media

In social media such as Facebook, the sharing of photos among users is common and enjoyable but also very dangerous when the uploader posts photo online without the consents from other participants in the same photo. As a solution, recent research has developed a fine-grained access control on social media photos. Every participant will be tagged by the uploader and notified through internal messages to initialise their own access control strategies. The appearance of participants will be blurred if they want to preserve their own privacy in a photo. However, these methods highly depend on the uploader’s reputation of tagging behaviours. Adversaries can easily manipulate unpermitted tagging processes and then publish photos, which should have kept confidential to the public in social media. In order to solve this critical problem, we propose developing a participant-free tagging system for social media photos. This system excludes potential adversaries through automatic tagging processes over two cascading stages: (1) participants are tagged through internal searching which is based on the portrait samples collected in initialisation stage for every new user; (2) the remaining untagged participants will be identified cooperatively through tagged users. In the evaluation, we carried out a series of experiments to validate our system’s efficiency and effectiveness. All the results demonstrate the tagging efficiency and effectiveness in protecting users’ privacy.