Designing Secure Sparse Coding via Multiple Random Unitary Transforms

In this paper, we propose a design method of secure sparse coding via multiple random unitary transforms (RUTs). The proposed method operates as an Encryption-then-Compression (EtC) system. The multiple RUTs will increase the security strength of the secure sparse coding. Despite the improvement in security strength, the rate-distortion performance does not deteriorate. It provides the same rate-distortion performance as that of sparse coding without encryption. We demonstrate its performance via simulation.