Abstract Recently, two chaotic image encryption schemes have been proposed, in which shuffling the positions and changing the grey values of image pixels are combined. This paper provides the chosen plaintext attack to recover the corresponding plaintext of a given ciphertext. Furthermore, it points out that the two schemes are not sufficiently sensitive to small changes of the plaintext. Based on the given analysis, it proposes an improved algorithm which includes two rounds of substitution and one round of permutation to strengthen the overall performance.
Received: 10 March 2008
Revised: 20 March 2008
Accepted manuscript online:
PACS:
05.45.Gg
(Control of chaos, applications of chaos)
Fund: Project supported by the Natural
Science Foundation of Shandong
Province, China (Grant No Y2007G43).
Cite this article:
Yang Su-Xiang (徐淑奖), Xu Shu-Jiang (王继志), Wang Ji-Zhi (杨素香) An improved image encryption algorithm based on chaotic maps 2008 Chin. Phys. B 17 4027
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