Fig. 3
From: Camera-based photoplethysmography in an intraoperative setting
Program structure of the presented ROI detection and tracking algorithm. a ROI detector which (initially) detects the skin, finds the ROI and registers and adapts the result for the NIR image. b Simplified flowchart of the whole program (detection and tracking) which runs separately for the RGB and NIR video. For some transitions between the program blocks, the data types are given (I: image, \(\tilde{I}\): adjusted image, \(\Omega _{...}^{...}\): image region, \({k}\): frame number). * pause after ROI reselection