公开(公告)号：KR100453683B1

公开(公告)日：2004-10-20

申请号：KR1020020014114

申请日：2002-03-15

Applicant: 한국전자통신연구원

Inventor： 김진호 ,  장호욱 ,  문경애 ,  김명준 ,  황영하

IPC: H04N1/387

CPC classification number: G06T1/0057 ,  G06T2201/0051 ,  G06T2201/0083 ,  H04N1/32203 ,  H04N1/32208 ,  H04N2201/3281

Abstract: Disclosed is a method for embedding and extracting a spatial domain blind watermark using a sample expansion. The sample expansion method using a sample expansion coefficient is introduced to basically improve a common disadvantage of the conventional watermarking method based on the patchwork method, for instance, the watermark is not robust against a compression attack such as JPEG. By applying the sample expansion to a sample group, the embedded watermark comes to contain a low frequency component more larger than ever, so that radio frequency component decreases as much. Thus, although the radio frequency component of the watermark is damaged by the image compression such as JPEG, it is possible to relatively reduce the damage of the watermark. Also, an adaptive watermark embedding method can be considered such that the embedded watermark value is proportional to an average value of the pixel. In order to overcome non-robustness that is a common disadvantage of the conventional methods based on the conventional patchwork method or the conventional modified patchwork method, not a single pixel but sample-expanded pixel is chosen, and there is proposed a spatial domain blind watermarking method using a watermark value that is proportional to an average value of pixel every tile.

Abstract translation: 公开了一种使用样本扩展来嵌入和提取空间域盲水印的方法。 引入使用样本展开系数的样本展开方法基本上改进了基于拼凑方法的传统水印方法的普遍缺点，例如，水印对于诸如JPEG的压缩攻击不具有鲁棒性。 通过将样本扩展应用于样本组，嵌入的水印会包含比以往更大的低频分量，使射频分量减少得更多。 因此，虽然水印的射频分量被诸如JPEG的图像压缩损坏，但可以相对减少水印的损害。 而且，可以考虑自适应水印嵌入方法，使得嵌入的水印值与像素的平均值成比例。 为了克服基于传统拼接方法或传统修改拼接方法的常规方法的普遍缺点的非鲁棒性，选择不是单个像素而是样本膨胀像素，并且提出了空间域盲水印 方法使用与每个像素的像素的平均值成比例的水印值。

公开(公告)号：KR100449803B1

公开(公告)日：2004-09-22

申请号：KR1020020037023

申请日：2002-06-28

Applicant: 한국전자통신연구원

Inventor： 황영하 ,  이기륭 ,  문경애 ,  김명준

IPC: G06T1/00

CPC classification number: G06T1/005 ,  G06T2201/0052 ,  G06T2201/0065 ,  H04N1/32149 ,  H04N1/3232

Abstract: Disclosed a method of designing a watermark having the power spectral density optimized so that the detection performance can be improved by employing the whitening filtered detection after the Wiener attack. The power spectral density of the watermark is designed using an optimization method that can improve the entire detection performance by reflecting the gain of the whitening filter after the Wiener attack. A higher detection gain is obtained using the whitening filter after the Wiener attack, and the expected value of the difference between test statistics of the two hypotheses that the watermark exists and the watermark does not exist, respectively, is maximized to optimize the detection performance. Regarding the expected value of the difference between the test statistics as an objective function, the power spectral density of the watermark, which corresponds to a maximum differentiated value of the power spectral density of the watermark using the Lagrange multiplier method, is obtained.

Abstract translation: 公开了一种设计具有优化的功率谱密度的水印的方法，以便通过在维纳攻击之后采用白化滤波检测来提高检测性能。 利用优化方法设计水印的功率谱密度，该方法通过反映Wiener攻击后白化滤波器的增益来提高整个检测性能。 在Wiener攻击之后使用白化滤波器获得更高的检测增益，并且分别存在水印存在和水印不存在的两个假设的测试统计量之间的期望值被最大化以优化检测性能。 关于作为目标函数的测试统计之间的差异的期望值，获得了与使用拉格朗日乘子法的水印的功率谱密度的最大微分值对应的水印的功率谱密度。

公开(公告)号：KR1020040001710A

公开(公告)日：2004-01-07

申请号：KR1020020037023

申请日：2002-06-28

Applicant: 한국전자통신연구원

Inventor： 황영하 ,  이기륭 ,  문경애 ,  김명준

IPC: G06T1/00

CPC classification number: G06T1/005 ,  G06T2201/0052 ,  G06T2201/0065 ,  H04N1/32149 ,  H04N1/3232

Abstract: PURPOSE: A method for designing a watermark considering a wiener attack and whitening filter detection is provided to improve the detection performance by using a watermark having power distribution density optimized by considering a wiener attack and whitening filter. CONSTITUTION: An expectation of a difference between test statistics of a hypothesis with a watermark and another hypothesis without a watermark is defined as a target function of the optimized method for improving the performance of detecting a watermark. The target function of the optimized method for improving performance of detecting a watermark is calculated by an expression using power distribution density of the original signal and power distribution density of the watermark. The power distribution density of the optimized watermark is obtained from the target function by using a Lagrange multiplier method.

Abstract translation: 目的：提出一种考虑到维纳攻击和白化滤波器检测的水印设计方法，通过使用具有通过考虑维纳攻击和增白滤波器优化的功率分布密度的水印来提高检测性能。 构成：假设水印的测试统计与水印的另一假设之间的差异的期望被定义为用于提高水印检测性能的优化方法的目标函数。 通过使用原始信号的功率分布密度和水印的功率分布密度的表达式来计算用于提高水印检测性能的优化方法的目标函数。 通过使用拉格朗日乘数法从目标函数获得优化水印的功率分布密度。

公开(公告)号：KR1020030075030A

公开(公告)日：2003-09-22

申请号：KR1020020014114

申请日：2002-03-15

Applicant: 한국전자통신연구원

Inventor： 김진호 ,  장호욱 ,  문경애 ,  김명준 ,  황영하

IPC: H04N1/387

CPC classification number: G06T1/0057 ,  G06T2201/0051 ,  G06T2201/0083 ,  H04N1/32203 ,  H04N1/32208 ,  H04N2201/3281

Abstract: PURPOSE: A method for inserting and detecting a spatial domain blind watermark using a sample expansion is provided to reduce damages of the watermark by restraining high frequency components of the watermark according to the sample expansion. CONSTITUTION: Pseudo binary random number blocks having certain size in row and column direction are generated, and a pair of samples according to the generated pseudo binary random number blocks are selected. The pseudo binary random number blocks are expanded in row and column direction according to the set sample pair. The expanded sample pair blocks are made to tiles in a certain number. A watermark bit corresponding to each tile is generated and the polarity of each tile is converted according to watermark bit information. The mean pixel value is multiplied by watermark insertion strength by tiles to calculate a watermark value to be inserted. Watermarks are inserted into the pixels of the tiles respectively and partial images to which the watermarks are inserted are gathered to obtain the finally watermarked image.

Abstract translation: 目的：提供一种使用样本展开来插入和检测空间域盲水印的方法，以通过根据样本扩展抑制水印的高频分量来减少水印的损害。 构成：生成在行和列方向上具有一定大小的伪二进制随机数块，并且根据生成的伪二进制随机数块块选择一对样本。 伪二进制随机数块根据设定的采样对在行和列方向上扩展。 扩展的样品对块被制成一定数量的瓷砖。 生成对应于每个瓦片的水印位，并且根据水印位信息来转换每个瓦片的极性。 平均像素值乘以瓦片的水印插入强度，以计算要插入的水印值。 将水印分别插入到瓦片的像素中，并收集插入水印的部分图像以获得最终加水印的图像。