This study proposes two methods of optical watermarking based on multiplexed time-varying signals for computational ghost imaging using the Hadamard matrices. The proposed methods can realize image fusion and dual optical encryption. The time-varying signal is encoded into a specific Hadamard coefficient in advance and hidden in the light source of the transmitting end as a multiplicative factor or loaded at the receiving end as an additive factor. Theory and experiments confirm the feasibility of this scheme. Moreover, the scheme is highly scalable and has potential applications in multispectral single-pixel imaging.

中文翻译：

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具有多重时变信号的计算重影成像

这项研究提出了两种基于多时变信号的光学水印技术，用于使用Hadamard矩阵进行计算重影。所提出的方法可以实现图像融合和双重光学加密。随时间变化的信号被预先编码为特定的Hadamard系数，并作为乘法因子隐藏在发送端的光源中，或者作为加法因子隐藏在接收端。理论和实验证实了该方案的可行性。此外，该方案具有高度可扩展性，并且在多光谱单像素成像中具有潜在的应用。