Information Technology Journal1812-56381812-5646Asian Network for Scientific Information10.3923/itj.2010.680.685YangXue YuXiaoyang ZouQifeng JiaJiaying 4201094Image encryption is essential to assure information security. Universal modular transformation is a widely applied encryption method, but it has some disadvantages such as a relatively small quantity of keys and insecurity. A uniform block encryption method is proposed in this study to improve the image entropy of encryption and an image is encrypted with the universal modular transform combined with a chaotic mapping. Experimental results show that this algorithm can provide good encryption quality and reach high safety. Moreover, the proposed algorithm is robust to shear attack and noise attack.]]>Zou, W. and H. Liu,20079133135Huang, L. and D. Xiao,20092474476Chen, M.,20061235237Zou, J., X. Tang and G. Li,2000031316Kwok, H.S. and W.K.S. Tang,20073215181529Fan, C. and C. Jiang,200412179184Huang, F. and Y. Feng,20071510961103Ren, H., Z. Shang and J. Zhang,2008814801483