Title: A NOVEL METHOD FOR SECURE IMAGE DELIVERY OVER MOBILE NETWORKS BASED ON ORTHOGONAL TRANSFORMS AND SCRAMBLING ALGORITHMS

Year of Publication: 2013
Page Numbers: 37- 41
Authors: Mohammad Malakooti, Vahid Saffari, Tawfik Saeed Zeki
Conference Name: The Third International Conference on Digital Information Processing and Communications (ICDIPC2013)
- United Arab Emirates

Abstract:


We have presented a novel method for secure image delivery over the mobile networks. Our method is based an Orthogonal Transform, Malakooti Orthogonal Transform (MOT), as well as Malakooti-Saffari Scrambling Algorithm (MSSA) to apply multiple levels of security on the image files prior to delivery. The image scrambling and Encryption techniques are applied to provide the sufficient security and to reduce the risk of any attack during the delivery over the mobile networks. Our method can be divided into four steps as following: First, the image file is converted into RGB color space, and then the MSSA algorithm is applied on each layer of RGB, Red, Green, and Blue Matrices in order to scramble the image pixels and to provide the first level of security. In the second step, scrambled, R, G, B matrices are divided into smaller blocks and then MOT, Discrete Cosine Transform (DCT), or Walsh-Hadamard Transform (WHT) is applied on each sub-block to provide second level of security on the image. In the third step, we have generated sequences of secret keys (key) by using Malakooti Randomized Key Generator (MRKG) Algorithm and XOR operation is applied on the elements of the sub-block and the elements of the secret keys to provide third level of security on the image. Finally, the scrambled and encrypted sub-blocks of three layers, R, G, B matrices are combined together to build a highly secured scrambled and encrypted image ready to be transferred over the mobile networks. Once the scrambled and encrypted image is transferred over the mobile networks, the reverse operation is applied to retrieve the original image. We applied our model on several different images and also calculated the MSE to show the efficiency and accuracy of our method over the existing ones. Since the mobile devices and wireless networks have a lot of limitations for the real time processing of the multimedia information, we have applied a fast orthogonal transform (MOT) and compared its result with DCT and WHT.