CCTV Footage De-identification for Privacy Protection: A Comprehensive Survey

Privacy preservation is a significant concern in our data-driven society, both in the social and political spheres. These concerns are amplified by the continuous emergence of technologies and services, expanding the boundaries of what is possible in our modern era. Technologies, such as audio-video surveillance, play an essential role in security and law enforcement but can potentially lead to privacy breaches. One of the approaches for privacy preservation in still images and video is de-identification which involves replacing or concealing personal identifiers to prevent unauthorized, unintended use or disclosure of personal information. This paper comprehensively reviews privacy and security issues in closed-circuit television (CCTV) data streams, representative state-of-the-art de-identification techniques for privacy protection. We also present a service scenario in which a MEC-enabled distributed system is used for CCTV footage de-identification and re-identification for individuals' privacy protection. Finally, we highlight open research challenges and future directions for privacy protection in CCTV footage.