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文章在小波频域高阶统计矩图象隐写分析基础上,将隐写分析问题扩充为多类问题,针对CorelDraw图象库5种常用的隐写方法进行了实验,结果表明该文方法不仅能检测出图象是否隐含数据,还能指出所用的隐写方法,识别率在90%以上。还提出了多类“类内类间分布图”,对于高维可分性好低维可分性差的图示问题,指导特征以及分类器的选择,具有很高的价值。 相似文献
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Robustness is one of the most important requirements of digital watermarking for many applications. Spread-spectrum based methods are not effective enough to ensure their robustness. By modeling digital watermarking as digital communications, several researchers proposed using error correcting coding (ECC) to improve robustness. However, an important fact that has long been neglected is that due to the imperceptibility requirement, the redundancy introduced by ECC will lead to a decrease of the magnitude of watermark signal. Therefore, a problem arises naturally: Could the usage of ECC effectively improve the robustness of watermarking? This paper addresses this problem from the perspectives of both theoretical analysis and experimental investigation. Our investigation shows that ECC cannot effectively improve the robustness of watermarking against a great majority of various attacks except for cropping and jitter attacks. Hence, ECC should not be considered as a universal measure that can be employed to enhance robustness of watermarking. 相似文献
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文章提出了一种基于小波域压缩扩展技术的无损图象数据隐藏方法。该方法先对图象作整数小波变换;随后使用压缩扩展技术在小波高频子带系数上嵌入数据。小波高频系数的拉普拉斯分布特性不但便利了压缩扩展函数的选择,而且使嵌入较大容量数据后的水印图象仍保持良好的视觉效果。实验结果表明,该方法无论在嵌入容量上还是嵌入数据后的图象视觉效果上,均达到当前世界上最好水平。 相似文献