Experimental analysis of classical and quantum-assisted lattice encryption for secure image communication

The rapid growth of digital image sharing has increased the need for secure image encryption methods. Existing classical image encryption techniques can protect images effectively, but their performance reduces when handling large multimedia data or facing advanced statistical and differential attacks. Moreover, many classical approaches are not designed to resist future quantum threats. This gap motivated us to explore lattice-based encryption, which is known for efficiency and post-quantum security. This work proposes a trapdoor-based image encryption scheme using lattice structures. The image pixels are first transformed into lattice vectors using a reverse lattice mapping process. A trapdoor mechanism is then applied to ensure secure encryption and exact decryption. To further strengthen security, quantum-assisted techniques are integrated into the lattice framework. The method is evaluated on sample images. The results show high PSNR, low MSE and strong SSIM values, confirming perfect image reconstruction. Additionally, improved entropy, number of pixels change rate (NPCR) and unified average changing intensity (UACI) values demonstrate enhanced resistance against statistical and differential attacks. The method achieves lossless encryption with improved security for post-quantum image applications.