Enabling search over encrypted multimedia databases

Performing information retrieval tasks while preserving data confidentiality is a desirable capability when adatabase is stored on a server maintained by a third-party service provider. This paper addresses the problem
of enabling content-based retrieval over encrypted multimedia databases. Search indexes, along with multimedia
documents, are first encrypted by the content owner and then stored onto the server. Through jointly apply-
ing cryptographic techniques, such as order preserving encryption and randomized hash functions, with image
processing and information retrieval techniques, secure indexing schemes are designed to provide both privacy
protection and rank-ordered search capability. Retrieval results on an encrypted color image database and se-
curity analysis of the secure indexing schemes under different attack models show that data confidentiality can
be preserved while retaining very good retrieval performance. This work has promising applications in secure
multimedia management.