Blockchain-Based Encrypted Image Storage and Search in Cloud Computing

In the traditional cloud computing system, existing ranked image search mechanisms will leak the similarity of search results, even cannot prevent malicious cloud servers from tampering with or forging results. Therefore, with the help of blockchain technology, we propose an encrypted image storage and search system. A threshold encryption method based on the matrix similarity transformation theory is designed to protect the similarity of search results. Besides, a hybrid storage structure based on blockchain and cloud server is designed to ensure the correctness and completeness of search results. Finally, we implement the prototype in Python and Solidity, and conduct performance evaluations on local Ethereum client. The theoretical analysis and performance evaluations using the real-world dataset demonstrate that our proposed system is secure and feasible.