  At present, more than a billion closed-circuit television (CCTV) cameras are
watching the world. These cameras garner a lot of visual information that is
often processed and stored in remote and centralized cloud servers. Multiple
occasions have revealed that this traditional approach is plagued with security
and privacy breaches. The breaches could be the interception of raw videos
while in transit to distant surveillance analytics centers (SAC), infiltration
to cameras and network video records (NVR), or abuse of cameras and stored
videos. Hence, the traditional video surveillance system (VSS) cannot guarantee
the protection of the privacy of individuals caught on CCTV cameras. Wherefore,
this paper proposes a Secure and Privacy-preserving Stored surveillance video
sharing (SePriS) mechanism for authorized users/nodes based on smart contracts,
blockchain (BC), and the enciphering of video frames using DAB, a mechanism
developed based on discrete cosine transform (DCT), advanced encryption
standard (AES), and block shuffling (BS) algorithm. The BC-based solution
creates an environment auspicious for creating decentralized, reliable SACs and
storage sites with secure and privacy-aware sharing of stored surveillance
videos across SAC nodes and by law enforcers, police departments, and courts
securely connected to the SAC nodes. The experiments and analyses validate that
the proposed BC-based SePriS solution achieves the design purpose.
