Secure facial imaging and non-contact heart rate measurement via computational ghost imaging

The secure transmission of image information is a crucial issue in communication, and facial information is a vital component of personal privacy. This paper proposes a remote photoplethysmography (rPPG) system with computational ghost imaging (CGI) optical encryption, offering the characteristic advantages of end-to-end encryption and non-contact heart rate (HR) measurement. Compared to rPPG methods based on array sensors, such as cameras, this method enables encryption to be performed simultaneously with imaging, rather than imaging first and then encrypting, which avoids the risk of leaking plaintext information during processing. This method only requires calculations when generating the coded patterns, which is advantageous over traditional encryption methods that require encryption after each imaging due to their lower computational requirement. Numerical simulations and experiments verify the feasibility and robustness of this method. The method proposed in this paper offers a fresh framework for robust, affordable, and secure facial imaging and HR measurement.