Multi-image Dual Chaotic Compression Encryption Method for Interferenceless Coded Aperture Correlation Holography

To improve the security and efficiency of multi-image encryption, this paper proposes a hybrid encryption method that combines Interferenceless Coded Aperture Correlation Holography (I-COACH) with chaotic modulation and compressed sensing techniques. The method constructs a dual-layer encryption framework, integrating optical and digital processing to overcome the limitations of single-domain schemes.In the optical layer, I-COACH is employed to encode multiple input images by recording their point spread holograms without interference, providing initial encryption and resistance against physical attacks. The resulting hologram is then processed using block-wise Discrete Cosine Transform (DCT) to achieve sparsity. Dual chaotic sequences perturb DCT coefficients to enhance key sensitivity and randomness. Finally, compressed sensing is applied to achieve secondary encryption while reducing the data volume by 30%, enabling efficient and secure storage or transmission. Experimental results demonstrate that the proposed method achieves an average Number of Pixels Change Rate (NPCR) of 99.44% and a Unified Average Changing Intensity (UACI) of 33.04% against differential attacks, with a ciphertext entropy of 7.9996 bit. Moreover, it exhibits excellent encryption performance in terms of key sensitivity, robustness, and resistance to statistical analysis. This method provides a practical solution for secure image application scenarios such as medical imaging and surveillance.