Separable Reversible Data Hiding in Encrypted VQ-Encoded Images

In this paper, a reversible data-hiding scheme in encrypted, vector quantization (VQ) encoded images is proposed. During image encryption, VQ-encoded image, including codebook and index table, encrypted by content owner with stream-cipher permutation to protect the privacy of contents. As for additional-data embedding, baseline method first proposed its corresponding optimized then given. By grouping one high-occurrence or multiple low-occurrence indices, series groups are constructed. Thus, modifying within same group according current to-be-embedded bits, data embedding can be realized. The optimal hiding capacity obtained optimizing coefficient different types groups. Separable operations extraction, decryption, recovery achieved on receiver side based availability encryption keys. Experimental results show that our achieve high satisfactory directly decrypted quality guarantee security reversibility simultaneously.