The Study Of Digital Image Scrambling Algorithm Based On Bézier Curve

Digital image scrambling as a pretreatment method for image encryption methods or information hiding has been widely used and highly valued. In recent years, many random scrambling methods have played an active role in research and application. But overall they still have the shortcomings, such as single criterion in algorithm, strict requirement in image's geometric configuration or bad in scrambling images statistical attack ability.According to the Bezier curve equation, this paper put forward a concept of Bézier blending on element (including Bézier blending on element and Bézier blending on sequence), discussed the related quality of Bézier blending and applied Bézier blending to digital image scrambling. To enrich digital image scrambling's contents and methods and to make a beneficial attempt to combine the theory and method of Computational Geometry with digital image processing, the methods and properties of Bezier curve were applied to Digital image scrambling in this paper.In this paper, many works has been done in the following aspects:1. This paper put forward a definition of Bézier blending(including Bézier blending on element and Bézier blending on sequence), and analyzed the properties and characteristics of Bézier blending combining the theory of cryptology.2. This paper put forward digital image hashing algorithm and unified image hashing algorithm based on position of the space and image hashing algorithm based on gray space images. And the algorithm has no differences in image scrambling process for square and off-square image.3. Based on rate of change of histogram of digital image, this paper put forward an evaluation method of the image scrambling effect and the evaluation method is proved reliable.4. This paper deeply analyzed the correlation of the parameters of digital image hashing algorithm based on Bézier blending and their influence on the result of the scrambling.Finally, this paper describes the prospects of the future, points out the future research and improvement, and indicates several hopeful exploration areas and direction.