Fig. 6.

Heart Rate measurement with the smartphone-based hyperspectral imaging system. (a) One frame extracted from the RGB mode video in facial skin monitoring with the smartphone camera under flashlight illumination. (b) The derived map of blood absorption information (coded according to the color bar shown in the right) overlaid with the raw grey-scale RGB image in (a). (c) Black curve: The frequency spectrum of temporal profile of blood absorption information content. Red curve: The heart rate reference from the PowerLab pulse sensor.