ADAPTIVE ROBUST WATERMARKING ALGORITHM BASED ON DCT-DOMAIN

Since current DCT-domain watermarking algorithm is poor self-adaptive, a new digital watermarking algorithm that combines encryption with adaptability is proposed. Before been embedding, it need to be Arnold transformed so that it can break the correlation of watermark's inter-related data, greatly increase the security of watermarking and reduce the errors may be caused in the watermark image transmission and extraction process. It can adaptively and dynamically adjust the strength of embedded watermark and coordinate the effectiveness and hidden character in the embedding process. Moreover, with data encryption technology, it can ensure the security of embedded information. The experiment shows that the algorithm has good robustness to median filtering, image shearing, salt-pepper noise and JPEG compression and other kinds of attack.