Yang Na, Gao Qiankun, Shi Yishi
Opt Express. 2018 Nov 26;26(24):31995-32006. doi: 10.1364/OE.26.031995.
In this paper, we propose a visual-cryptographic image hiding method based on visual cryptography (VC) and volume grating optics. The secret image is converted to the encrypted visual keys (VKs) according to the normal VC algorithm. Then the VKs are further embellished to the QR-code-like appearance and hidden as the holographic optical elements (HOEs), which are fabricated by the holographic exposure of photopolymer. In the decryption process, the fabricated HOE-VKs are illuminated with the laser beam. The reconstructed VKs are overlaid to extract the hidden information directly in the optical facility, without additional computation. Optical experiments verify that the VKs in HOE mode improves the system with high security and good robustness on the random noise attack. Besides, the volume grating nature also enlarges the system bandwidth by using the multiplexing technique. The proposed method may provide a promising potential for the practical image hiding systems.
在本文中，我们提出了一种基于视觉密码术（VC）和体光栅光学的视觉加密图像隐藏方法。根据常规的VC算法，将秘密图像转换为加密的视觉密钥（VK）。然后，将这些VK进一步修饰成类似二维码的外观，并作为全息光学元件（HOE）隐藏起来，这些元件是通过光聚合物的全息曝光制造的。在解密过程中，用激光束照射制造好的HOE-VK。将重建的VK叠加起来，可直接在光学设备中提取隐藏信息，无需额外计算。光学实验表明，HOE模式下的VK提高了系统的安全性，并且在随机噪声攻击下具有良好的鲁棒性。此外，体光栅特性还通过复用技术扩大了系统带宽。所提出的方法可能为实际的图像隐藏系统提供有前景的潜力。
