A Fast and Secure Diffusion Key-Based Colour Image Encryptions Using One-Dimensional Chaotic Maps

Images are a highly valuable medium for communicating data, as they possess the unique capability to visually represent information and convey a multitude of messages. Unfortunately, there is currently a deficiency in the development and research of rapid encryption methods specifically designed for colour images. This paper proposes a rapid and reliable scheme for encrypting colour images through the utilisation of one-dimensional (1D) chaotic maps in diffusion key-based encryption. The proposed technique involves an initial step of separating the three parts, namely blue, green, and red. Following this, the three components are horizontally concatenated. Chaotic key-based diffusion operations are performed on individual pixels that have been selected by indexing sequences based on chaotic maps. This process is repeated for each selected pixel. The diffused output is partitioned into three constituents and merged to produce the cipher images. The proposed method is deemed to be efficient due to its utilisation of a straightforward and effective colour image encryption procedure, coupled with the repeated use of a single 1D chaotic map. This approach results in a notably fast encryption process. The security of the proposed method is attributed to the utilisation of individual pixel diffusion operations based on chaotic keys. Based on the computer simulations and analysis on security, it has been determined that the suggested scheme is both efficient and secure in its ability to encrypt colour images of varying dimensions.