如何达到健壮性和透明性之间的平衡是数字水印技术最大难题。二者此消则彼长。 本文将零水印概念具体贯彻到工程图产权保护领域。算法基于ObjectARX 技术,取出原始工程图的特征参数得到数字条形码序列,检测时以之与被测图数据比较,计算相关系数,判断水印有无。实验结果表明,该算法在保证完美透明性的前提下,具备相当的健壮性。 关键词 计算机应用数字水印 相关系数 健壮性 Abstract: The tradeoff between robustness and invisibility remains the bottleneck in digital watermarking technology. To solve this problem, a new concept, null-watermark technique, is introduced and instanced in this paper. The eigenvector is extracted from the original drawing and kept in some certain database in accordance with digital watermarking security system. While detecting the eigenvector is compared with data of tested drawing to evaluate the correlation coefficient, on which a judgment of watermark existence will be made. Experiments verify the robustness of this approach. Key words: computer application ; digital watermark; correlation coefficient; robustness