CryptFine: Towards secure cloud based filtering in encrypted domain

Cloud computing is a shift towards increasing the capabilities dynamically without investing in new infrastructure. Enormous storage of data and high-speed computing to customers over the internet can be accomplished using cloud. Security of data in cloud is one of the chief concerns which acts as an obstacle in the realization of cloud computing. Along with quick expansion and application of cloud computing, users concern more and more regarding security and privacy issues involved in these techniques. An efficient method to perform privacy preserving image filtering operations in encrypted domain over cloud is proposed in this paper. The proposed method provides facility for distributed secure processing and storage of the secret image using Shamir's secret sharing method and Chinese remainder theorem. The plain secret image is divided into number of shares in a manner that each share by itself does not reveal any meaningful information about the original image, while collectively, they retain all the information. Two secret keys are used to avail security of image shares and without knowledge of such keys, one cannot restore the secret image back. Hence, the proposed scheme is highly secured and the image can be processed without revealing any information at the cloud data center. Experimental results demonstrate that number of image filtering procedures for enhancement can be carried out efficiently in encrypted domain using the proposed method.