A Robust Watermarking Scheme for Encrypted JPEG Bitstreams with Format-Compliant Encryption

Abstract

JPEG is a very popular image compression standard in Internet. To simultaneously provide image content protection and copyright protection, in this paper, we provide a robust watermarking scheme for encrypted JPEG bitstreams. The JPEG bitstream is enciphered with a format-compliant encryption to produce another JPEG bitstream with meaningless image content. The watermark embedder can directly embed the message into the encrypted JPEG stream by modifying the quantized DC coefficients without performing decryption or decompression in advanced. As for the watermark extraction, anyone who has the embedding key can extract the watermark from the encrypted watermarked JPEG bitstream and the decrypted watermarked JPEG bitstream. All the watermark embedding and extraction procedures are performed in the compressed domain. We conduct the experiments to verify the effectiveness of the proposed JPEG encryption and watermarking algorithms. Our experimental results also show that the decrypted watermarked images have high visual fidelity, and the watermarking scheme is robust against some common watermarking attacks.