A non-contact heart rate measurement method resistant to illumination changes based on fast wavelet transform and second-order blind identification in far-field environments

Heart rate is a key parameter for evaluating a person's physiological condition. In recent years, there have been many researches on remote heart rate measurement. However, these methods are mostly conducted in close-range scenarios, making them inapplicable in many scenarios. Remote photoplethysmography provides more possibilities for heart rate measurement in far-field environments. Moreover, the performance of heart rate measurement will be significantly reduced when the subject's movement and the illumination changing. We propose a rPPG framework for heart rate detection, which selects a larger region of interest using feature point tracking in far-field environments. The combination of fast wavelet transform and second-order blind identification is used to resist illumination interference and most of the motion interference. Singular spectrum analysis is then used to resist residual motion interference. In addition, we collected a database of illumination changes in far-field environments and tested our framework with it. The results show that our method is superior to all previous methods.