Quantum Colour Image Encryption Algorithm Based on Chaotic Systems

To enhance the security of image data, the incorporation of a chaotic system with quantum image encryption was proposed. Bitwise XOR operation was performed on a test image by applying the Chen chaotic system, and the obtained colour image was expressed as a quantum superposition state. The unitary matrix generated by the logistic chaotic sequence was then employed for scrambling the quantum image. In addition, to achieve the objective of quantum image encryption, another chaotic sequence was generated for randomly interchanging the red, green, and blue colour components of each pixel in the quantum image. Results obtained from simulation experiments conducted on a classical computer demonstrate that the grey histogram of the encrypted image is smooth, and the pixel intensity range is distributed uniformly between the values of 0 to 255. The correlation between adjacent pixels is found to be low, with the correlation coefficient values being 0.001 6, 0.001 7, and 0.003 8 for the red, green, and blue channels, respectively. Furthermore, the high key sensitivity of the proposed algorithm can effectively resist high intensity, exhaustive, and statistical attacks. Hence, the proposed algorithm can feasibly provide the required security for image data.