Zhang Jian

A Chaotic Algorithm of Image Encryption Based on Dispersion Sampling

Through the analysis of relationship between chaotic characteristics and cryptology, putting forward a chaotic algorithm of image encryption with double keys. Using the discrete Logistic map to produce the chaotic sequence, the original value of the sequence is regarded as the secret key. Then using the discrete Logistic map to produce the corresponding scrambling sequence, in order to utilize it to carry out the gray scrambling and location scrambling on the pixels that getting discretely from the image, so as to realize the image encryption. Finally using Matlab to actualize the simulation experiment, and the result indicates that this algorithm has widest secret keys space, and the ability of resisting statistic attack.

Image Hiding Algorithm Based on Displacement Block on Odd-Even Layer

Base on the thought of shifting histogram, a new reversible data hiding algorithm is proposed. This method utilizes two adjacent pixels of which difference is 1 to hide information, for the sake of improving payload, odd-even layer adopt different block mode and modification methods for gray values. Plenty of experimental results show that, comparing with other algorithm, the proposed method has advantages of large hiding capacity and high quality of carrier image after hiding information.