Secure transmission of images based on chaotic systems and cipher block chaining

The ever-growing penetration of communication networks, digital and Internet technologies in our everyday lives has the transmission of text data, as well as multimedia data such as images and videos, possible. Digital images have a vast usage in a number of applications, including medicine and providing security authentication, for example. This applicability becomes evident when images, such as walking or people's facial features, are utilized in their identification. Considering the required security level and the properties of images, different algorithms may be used. After key generation using logistic chaos signals, a scrambling function is utilized for image agitation in both horizontal and vertical axes, and then a block-chaining mode of operation may be applied to encrypt the resultant image. The results demonstrate that using the proposed method drastically degrades the correlation between the image components and also the entropy is increased to an acceptable level. Therefore, the image will become greatly resistant to differential attacks. However, the increasing scrambling rounds and the decreasing number of bits of the blocks result in increasing the entropy and decreasing the correlation. (C) 2013 SPIE and IS&T [DOI:10.1117/1.JEI.22.1.013025]