Fig. 11
From: Spatio-temporal and -spectral feature maps in photoplethysmography imaging and infrared thermography
Adult face video w/o (top) and w/ movement (bottom): mean intensity mapping of 10-s segments. The round optical markers are doubled due to movement. Furthermore, motion blur reduces the detail in the facial region. The movement of the arm is not visible due to the temporal low-pass effect (bottom). The ROIs marked for evaluation were manually chosen and correspond to the background (\(ROI_\text {BG}\); blue) and to a region that was expected to show pulsatility (\(ROI_\text {PULSE}\); red)