Algorithm 4 A step-by-step image encryption scheme.

Input: Plain image $P_i$. Output: Cipher image $C_i$. Begin  Examine the dimensions of $P_i$ (i.e., M, N, grayscale or RGB color image) and Change it into a 1-D vector of pixels (length $=M\times N$ or $3\times M\times N$ for grayscale and color images, respectively)  Alter the intensity values into the range $(0,1)$ by mathematical operation included into the arrangement as the state values of the proposed mapping.  Split$P_i$ into two vectors ($P_1$ and $P_2$ of lengths $M\times N/2$ each.  Generate the chaotic sequence by selecting two of the proposed maps (e.g., Execute Equations (1) and (2))  Change the chaotic sequence (different maps in Figure 2 can be used for each half of $P_i$).  Iterate the chaotic sequence for $P_1$ for scrambling $P_{1p}$ row by row and column by column (starting from the first row and the first column).  Compute the next quantized chaotic pair using the 2nd proposed map to scramble $P_{2p}$ for $P_2$ with the second chaotic sequence, and reiterate this step n times1  Combine the two encrypted image halves (each half has its own encryption parameters) and mix the pixels of the combined image.  Permute $S_{k_i}$ using the 3rd proposed map for the secret key.  Construct the new vector of mistook pixels $S_{P_i}=S_{K_i}$ (index, size = $M\times N$).  Adjust and changes the vector $S_{P_i}$ realizing that every component of level gray ranges in [0,255] utilizing the 4-th proposed chaotic map and the accompanying condition: $S_{P_i}\left(i\right)=\mathrm{mod}(\mathrm{round}\left({10}^{12}{S}_{P_i}\left(i\right)\right),256)$, where $1\le i\le M\times N$.  Create the diffused vector $S_{D_i}=S_{P_i}\oplus S_{K_i}$, where ⊕ denotes the bit-wise exclusive OR  Create the final matrix with cipher image C${}_i$ = reshape ($S_{D_i}$, M, N)  Determine the encryption image matrix and spare as $C_i$. End