Self-embedding Fragile Watermarking Scheme Combined Average with VQ Encoding

摘要

Combined average encoding with vector quantization (VQ) encoding, a new self-embedding fragile watermarking scheme is proposed. To take into account watermark payload, localization accuracy and recovery quality, the 6-bit average-watermark of a 2 × 2 original block and the 8-bit VQ-watermark of a 4 × 4 block of image high-frequency component are generated and hidden in the corresponding mapping blocks of them based on secret key, respectively. To improve the tamper detection performance, the validity of a 2 × 2 block is determined by combining the average-watermark with the VQ-watermark. The average, VQ and inpainting recovery operations are executed in sequence to improve the recovery quality especially for a larger tampering ratio. Simulation results demonstrate that the proposed scheme not only provides a better invisibility and security against the known counterfeiting attacks, but also allows image recovery with an acceptable visual quality up to 70% tampering ratios.