Sequential quantization strategy for data embedding and integrity verification

Quantization-based embedding has been used for integrity verification in semi-fragile watermarking. However, some of the illegal modifications cannot be detected in the normal quantization-based methods, especially when the host values (i.e., the values chosen in a host signal for data embedding) are independent from each other. In this paper, a sequential quantization strategy (SQS) is proposed to make the modulation of a host value dependent on a certain number of the previous ones. Therefore, a balance between security improvement and tamper localization can be achieved for integrity verification. Furthermore, the proposed SQS is incorporated with a reversible data hiding mechanism. A new watermarking algorithm is then generated for mesh authentication. The experimental results show that the chance to detect illegal modifications is increased by adopting the SQS while the property of reversibility is achieved.