Figure 6. a) to e) Representative image frames of a white 2 x 2 pixel square moving from left to right at 50 ms per frame and being b) partially to c) completely occluded by a crossing 2 x 2 pixel red rectangle. f) VOC response of our proof-of-concept 20-pixel sensor tracking this moving occluded square. Red vertical dashed lines indicates the time periods of partial b) and complete occlusion c).