Image encryption based on pixel transposition and Lehmer Pseudo random number generation
Ranjan Kumar H S, Safeeriya S. P. Fathimath, Surendra Shetty, Ganesh Aithal · 2017
With the increased cryptanalysis, securing multimedia data against different types of attacks is a challenging task. This can be avoided by using multimedia encryption. The paper introduces a unique technique to encrypt images in two-stages using pixel transposition and Lehmer randomization concept. In the first stage, a standard sorting algorithm is applied on pixel of original image. Duplicate pixel values are eliminated to generate initial transposed image. Image pixel position values are used as unique security attribute and are fetched from the image with respect to initial transposed image and are written as text file. The second stage provides an extra level of security to position values (security attributes) and initial transposed image. Security attribute is further secured by encrypting using logarithmic operation and cipher image is produced by swapping pixels of initial transposed image with the sequence of pseudo random numbers generated with the aid of Lehmer Random Number Generator. The size of generated cipher image is several times smaller than that of original image. The analysis shows that the algorithm is resistant to statistical and differential attacks.