针对基于局部熵进行加密图像视觉安全性评估存在块效应的局限性,引入图像的边缘特征,通过共有边缘来衡量加密图像与原始图像的边缘相似度,消除了块效应。由于局部熵对加密等级低的图像不敏感,边缘相似度对加密等级高的图像不敏感,将两...针对基于局部熵进行加密图像视觉安全性评估存在块效应的局限性,引入图像的边缘特征,通过共有边缘来衡量加密图像与原始图像的边缘相似度,消除了块效应。由于局部熵对加密等级低的图像不敏感,边缘相似度对加密等级高的图像不敏感,将两个评估方法进行自适应融合,提出SLEES(Local Entropy and Edge Similarity,SLEES)指标。通过改变图像像素位置和图像像素值的加密方式处理图像和视频帧进行测试,实验结果表明,SLEES指标相比传统评估指标有更好的鲁棒性,评估范围更广。展开更多
A paper information anti-fake and tamper-proofing method based on human visual characteristics and morphol-ogy screen coding technology is proposed. Through controlling the distribution of mathematical morphology of s...A paper information anti-fake and tamper-proofing method based on human visual characteristics and morphol-ogy screen coding technology is proposed. Through controlling the distribution of mathematical morphology of screen dot-matrix,warning mark and information are hidden in the background texture. Because of the differ-ences between human vision and the duplicate characteristics of copy machine,warning mark which can not be discriminated by human eyes will emerge after copy. Tampered or fake certificates can be verified by compar-ing embedded information which is extracted from scanned image of certificate with plain text printed on the certificate. This method is applied in many bills and certificates. Experimental results show that the identifica-tion accuracy is above 98%展开更多
文摘针对基于局部熵进行加密图像视觉安全性评估存在块效应的局限性,引入图像的边缘特征,通过共有边缘来衡量加密图像与原始图像的边缘相似度,消除了块效应。由于局部熵对加密等级低的图像不敏感,边缘相似度对加密等级高的图像不敏感,将两个评估方法进行自适应融合,提出SLEES(Local Entropy and Edge Similarity,SLEES)指标。通过改变图像像素位置和图像像素值的加密方式处理图像和视频帧进行测试,实验结果表明,SLEES指标相比传统评估指标有更好的鲁棒性,评估范围更广。
基金key scientific and technological project foundation of Tianjin
文摘A paper information anti-fake and tamper-proofing method based on human visual characteristics and morphol-ogy screen coding technology is proposed. Through controlling the distribution of mathematical morphology of screen dot-matrix,warning mark and information are hidden in the background texture. Because of the differ-ences between human vision and the duplicate characteristics of copy machine,warning mark which can not be discriminated by human eyes will emerge after copy. Tampered or fake certificates can be verified by compar-ing embedded information which is extracted from scanned image of certificate with plain text printed on the certificate. This method is applied in many bills and certificates. Experimental results show that the identifica-tion accuracy is above 98%
