A Robust Watermarking Algorithm for Exchange Ciphers Using Homomorphic Encryption
Haibo Jin, Siyu Shang · 2022
With the continuous development of cloud technology, multimedia information can be stored and calculated on the cloud server, bringing convenience and privacy leakage. In order to protect the copyright of digital images, a robust watermarking algorithm based on homomorphic encryption in a cloud environment was proposed by combining homomorphic encryption technology with digital watermarking technology. Firstly, the user uses the Paillier encryption system to encrypt the original image and the watermark information related to the user's identity to obtain the encryption image and encryption watermark, which are uploaded to the cloud server for watermark embedding; In the encryption domain, the non-standard wavelet S-transform and the homomorphism of Paillier encryption system are used to embed the encryption watermark. In the image retrieval stage, users can directly extract the watermark in the encryption domain or extract the plaintext watermark information from the decrypted plaintext image with the watermark. The experimental results show that the decrypted image with a watermark has good transparency, and the embedded watermark has strong robustness to common image processing operations.