Multi-image hiding and decoding method based on invisible visual password

The invention discloses a multi-image hiding and decoding method based on an invisible visual password, and relates to the field of visual passwords. The hiding method comprises the following steps: acquiring a plurality of secret images; performing coding processing on each secret image by adopting a visual password coding principle to obtain a plurality of visual keys and a public key; and hiding the plurality of visual keys in a pure phase mask by adopting a phase recovery algorithm under different diffraction distances to obtain a plurality of phase keys. According to the method, multi-image hiding is realized through invisible visual passwords, and the hidden information capacity is greatly improved while the security in multiple aspects is ensured, so that the hiding and transmission efficiency is improved. 本发明公开一种基于不可见视觉密码的多图像隐藏和解码方法，涉及视觉密码领域；该隐藏方法包括：获取多张秘密图像；采用视觉密码编码原理对每一张秘密图像进行编码处理，得到多张视觉密钥和一张公共密钥；在不同的衍射距离下，采用相位恢复算法将多张所述视觉密钥隐藏到纯相位掩膜中，得到多张相位密钥。本发明通过不可见视觉密码实现多图像隐藏，可在保证多方面安全性的同时又大大提高了隐藏信息容量，从而提高隐藏和传输效率。