基于差分信噪比的图像置乱效果评价研究

Study on image scrambling effect based on mean square signal-to-noise rate of difference image

针对基于均方信噪比的置乱程度评价法不能客观地反映图像置乱效果好坏的不足,首先对置乱前后的图像进行差分运算并得到其相应的差分图像,其次计算两差分图像之间的均方信噪比值作为图像置乱效果评价的新准则,提出了基于差分图像和均方信噪比相结合的图像置乱效果评价新方法。实验结果表明,该方法能够有效地描述图像的置乱程度,能够反映出置乱次数与置乱程度之间的关系,并且与人的视觉感知基本一致。

Considering that the mean square signal-to-noise rate based image scrambling degree evaluation method has not been capable of reflecting the image scrambling result good or bad in actual fact. First, the difference images of the original image and scrambled image is obtained by means of difference operation on two images, then the mean square signal-to-noise rate of two difference images is acted as the new criteria of image scrambling effect evaluation. New image scrambling effect evaluation method based on difference image combined with the mean square signal-to-noise rate is proposed. Experimental results show that the proposed method is effective to describe the relation between the scrambling effect and the number of iterations in the scrambling techniques, which largely consists with human vision.