【摘要】 提出了一种基于傅立叶描述子的二维工程图的数字水印方法。该方法通过从工程图中提取特定顶点构造出复值信号量再进行傅立叶变换,通过对变换后的傅立叶变换系数幅值进行调制,嵌入符合N(0,1)分布的伪随机水印序列。通过实验确定水印检测中相关测试的阀值,从而根据相关值检测水印的存在与否。实验结果证明这种方法对平移、旋转、添加及删除部分实体等攻击具有良好的鲁棒性。更多还原

【Abstract】 A Fourier descriptor based digital watermarking method is proposed for 2-dimensional Engineering drawings.The specific coordinates of vertices in the 2D engineering drawings are extracted to construct correspondence complex signal which is in turn transformed by Fourier transformation.By modifying the FFT magnitude coefficients,the N(0,1) distribution pseudo random watermark sequence is embedded into the 2D engineering drawings.The algorithm detects the watermark by a specific correlation coefficient threshold,which is determined by threshold correlation experiments.The experimental results show that the proposed algorithm is robust to the attack of rotation,translation,entities addition and deletion.更多还原