Image Encryption Based on Pixel Decomposition

Decomposing an image into smaller elements for encryption can make the image encryption algorithm more complex, resulting in better encryption effects. This paper proposes an image encryption algorithm based on image decomposition. The proposed algorithm decomposes the pixel values of the plain image into smaller units and performs scrambling and diffusion operations based on them. For an image of size, M × N, the algorithm first decomposes the image pixel values with a bit depth of 8 into two 4-bit binary bits, which are then converted into two integers between 0 and 15, so the original M × Nsized image matrix is transformed into an M × 2N-sized data matrix. Then, the data matrix is scrambled using the Zigzag transform and subjected to XOR diffusion operations. Finally, the scrambled matrix is reversely transformed into a matrix with M×N size, and another round of diffusion operation is performed to obtain the cipher image. Experiments were conducted on three classic images. Experiment results showed that the proposed algorithm has good security and high effective ness, meeting the requirements of secure transmission of images in networks. © (2024) All rights reserved.