Digital Watermarking Authentication and Restoration for Chinese Calligraphy Images

In this paper, a semi-fragile watemiarking method for authentication and automatic restoration of Chinese calligraphy images is proposed using the pinned sine transform (PST). The watermarking system can locate the content of image that has been tampered maliciously with high accuracy. In particular, the watermarking scheme is very sensitive to any texture alteration in the watemiarked images, which is crucial for calligraphy image analysis. The tampered portions could be approximately restored. Results of simulation experiments are presented to demonstrate the effectiveness of the proposed method.