基于DCT的自适应盲数字水印.PDFVIP

包 装 工 程 第38 卷 第3 期 ·192 · PACKAGING ENGINEERING 2017 年2 月 基于 DCT 的自适应盲数字水印 周晓娟，孙建召 （河南经贸职业学院，郑州 450018 ） 摘要：目的 为提高彩色图像数字水印的抗攻击性能，提出一种新的、鲁棒性强的DCT 自适应水印算法。 方法 算法中利用 Arnold 变换对水印图像进行预处理，自适应选择强度因子。根据DCT 变换原理，并 利用其DC 系数的形成过程，不需进行DCT 变换，在空域中便可计算出8 ×8 分块的DC 系数。根据DC 系数修改量的分布特点，直接在空域中完成水印的嵌入。结果 该数字水印算法具有良好的透明性和稳 健性，同时对涂抹、旋转、剪切、叠加噪声等常见攻击具有较强的鲁棒性。结论 该算法在保证水印隐 蔽性的同时能够抵抗一定程度的攻击，满足版权保护和数字防伪的需要。 关键词：彩色图像；数字水印；Arnold 变换；DCT 变换 中图分类号：TP391 文献标识码：A 文章编号： 1001-3563(2017)03-0192-05 Self-Adaptive Blind Digital Watermarking Based on DCT ZHOU Xiao-juan, SUN Jian-zhao (Henan Institute of Economics and Trade, Zhengzhou 450018, China) ABSTRACT: The work aims to put forward a new DCT self-adaptive watermarking algorithm with strong robustness to improve the anti-attack performance of color image digital watermarking. In the algorithm, Arnold transform was used to preprocess the watermark image, and the intensity factor was adaptively selected. According to the principle of DCT transform and by means of the formation process of its DC coefficient, DCT transform was not required and 8×8 blocked DC coefficient could be calculated in the spatial domain. According to the distribution characteristics of DC coefficient modifiers, the watermark embedding was directly completed in the spatial domain. The digital watermarking algorithm had good transparency and robustness, and it also had strong robustness regarding painting, rotation, cutting, superim- posed noise and other common assaults. The algorithm can ensur