Remote photoplethysmography (rPPG) is a noncontact heart rate (HR) measurement technique. The current heart rate measurement methods based on rPPG all require ideal lighting conditions, but the lighting in real scenes is complicated, Therefore, this article proposes a robust heart rate measurement method when unstable light (time-varying light and uneven spatial illumination) exists. First, the method locates the ROI(Region of Interest) area of ​​the face, divides it into blocks, and uses the color signals of different sub-blocks to establish a three-dimensional rPPG model. Second, the method performs logarithmic operations on each frame of the image to convert the relationship between the illumination component and the reflection component from a product to a sum so that the reflected component and noise can be separated in the frequency domain. Then, the ensemble empirical mode decomposition (EEMD) is used to decompose the reflected component, and the obtained intrinsic mode function (IMF) is applied to obtain the waveform reflecting the change in the heart rate. Finally, the signal quality (SQ) of each ROI sub-block is calculated, and the high-quality signals are combined to reconstruct the heart rate signal.

远程光电容积描记法（rPPG）是一种非接触式心率（HR）测量技术。当前基于rPPG的心率测量方法都需要理想的照明条件，但实际场景中的照明比较复杂，因此，本文提出了一种在存在不稳定光（时光变化和空间照度不均匀）的情况下鲁棒的心率测量方法。首先，该方法定位人脸的ROI（感兴趣区域）区域，将其划分为块，然后使用不同子块的颜色信号建立三维rPPG模型。其次，该方法对图像的每一帧执行对数运算，以将照明分量和反射分量之间的关系从乘积转换为总和，从而可以在频域中分离反射分量和噪声。然后，使用集合经验模式分解（EEMD）分解反射分量，并应用获得的固有模式函数（IMF）获得反映心率变化的波形。最后，计算每个ROI子块的信号质量（SQ），并且将高质量信号组合以重建心率信号。