War Optimization Method for Image Encryption Algorithm Based on A Chaotic Bit-Plane Decomposition

Abstract

In this paper, develop image encryption algorithm based on a chaotic bit-plane decomposition and optimization algorithm of a War
Optimization Algorithm (WOA). Initially, utilization of SHA-256 hash algorithm for computing the plaintext images hash parameter as
initial parameter of the fractional Lorenz hyperchaotic system after the process. Use the chaotic sequence for permuting plaintext image in
a bit plane to achieve the scrambled images. After that, block the scrambles image into four sub images of similar size and count the hash
parameter of every row of every block through the SHA-256 hash algorithm as the initial parameter of the Sine-Tent Logistic chaotic system.
Utilize the achieved chaotic sequence to substitute the images. After that, the four sub-block images to get the last encrypted image and the
population can be achieved. At last, utilization information entropy of ciphertext images as the fitness function of WOA. Choose the
ciphertext image with the optimal information entropy of ciphertext images as the fitness function of the WOA. Select the ciphertext image
with the best information entropy from the population as the optimal encrypted image, and then, return the position value of the best war
source meanwhile. The proposed method is implemented in MATLAB and performance is analyzed with performance metrices. The
proposed method is compared with the conventional techniques.