1.引言多媒体数据的数字化为多媒体信息的存取提供了极大的便利,也极大地提高了信息表达的效率和准确性。同时随着网络的日益普及,网络发布形式逐渐成为多媒体信息交流的一种重要形式,伴随而来的是多媒体数据的安全问题,即版权保护问题。数字水印技术,作为信息隐藏技术的一种重要应用,为实现有效的信 1. Introduction The digitization of multimedia data provides great convenience for the access of multimedia information and greatly improves the efficiency and accuracy of information expression. At the same time, with the increasing popularity of the Internet, the form of network publishing has gradually become an important form of multimedia information exchange, accompanied by the security of multimedia data, that is, the issue of copyright protection. Digital watermarking technology, as an important application of information hiding technology, in order to achieve effective letter