Research on Watermark Tampering Blind Recognition Algorithm Based on Recognition Factor

As an important protection method of digital copyright, whether digital watermarking technology can effectively identify tampering attacks and protect watermark information is an important research topic in the field of digital copyright. In this paper, a dual watermarking algorithm based on discrete cosine transform and discrete wavelet transform in gray space is designed. The algorithm embeds a kind of identification factor while embedding a robust watermark, which can intuitively judge the attack mode of the image and has good robustness. Simulation experiments show that the algorithm can effectively protect the watermark information after being subjected to different tampering and attack, and solves the problem that a single watermark cannot have two characteristics.