Interdisciplinary Integration and Engineering Applications
ZHOU Yunliang, HE Yuanxia, FENG Ziqi, ZHENG Naiyi, XU Xiaogang, XU Guanlei, CHEN Shaohui
Blood pressure is a key indicator of cardiovascular health. To monitor daily blood pressure at home, researchers continue to use non-end-to-end measurement methods, such as combining multiple physiological signals, in addition to traditional blood pressure meters. These methods present some disadvantages: collecting multiple physiological signals is difficult and expensive, and maintaining the time synchronization of signal collection is challenging. Currently, the end-to-end method, which uses face videos to predict blood pressure, has widened the application areas to an extent; however, in most methods, selecting the areas of interest and limited prediction accuracy remain unresolved issues. To solve these problems, this paper proposes a remote blood pressure prediction method based on a multi-scale attention structure in visible light, called EBP-Net. First, each face video candidate window is classified, the effective skin region is extracted by regression, the remote Photoplethysmography (rPPG) signal is extracted from the continuous effective face region by optical flow-based technology, and the complete rPPG signal is filtered by wavelet transform. Robust rPPG signals are extracted using methods such as detrending. Second, EBP-Net introduces a new Efficient Multi-scale Attention (EMA) module and Multi-Scale Fusion (MSF) module, which can enhance the features of depth vision representation without reducing the channel dimension and significantly improve the model's ability to understand and predict physiological signals by capturing and hierarchically expressing multi-scale features. In experiments, Systolic Blood Pressure (SBP) is categorized as grade C according to the British Hypertension Society (BHS) on both datasets, while Diastolic Blood Pressure (DBP) is categorized as grade B. The Mean Absolute Error (MAE) values are 6.82 and 5.17 mmHg for systolic and DBP, respectively, which are lower than those in recent comparable studies. Compared with other models, this method has better generalization ability, a lower error rate, and provides effective methods and suggestions for the detection blood pressure level from face videos.