Measurement of Encryption Quality of Bitmap Images with RC6, and two modified version Block Cipher


With the fast evolution of digital data exchange, security informationbecomes much important in data storage and transmission. Due to the increasinguse of images in industrial process, it is essential to protect the confidential imagedata from unauthorized access. In this paper, RC6 with two modified version 512bit RC6 and 640 bit RC6-Cascade encryption algorithms will be analyzed toinvestigate the encryption efficiency for them to digital images and providing anew mathematical measure for encryption efficiency. Detailed results in terms ofsecurity analysis and implementation are given. Comparative study with threeversions of RC6 encryption algorithms is shown the superiority of the modifiedalgorithms. Three measuring quality factors will be considered to evaluate andcompare between the three encryption algorithms RC6, 512 RC6, and 640 RC6-Cascaded. These measuring factors are the maximum deviation, the correlationcoefficient and irregular deviation.