A snapshot from the pedestrian tracking application. In the filter overview, to the left, the walkway network and the sensor footprint are illustrated. The pedestrians are represented with particle mixtures. Six pedestrians have been detected, but just three are detected in the current frame, seen in the image to the right. Those detections are marked by rays from the sensor location to each target in the filter overview. One target is outside the field-of-view and its particle cloud is more outspread.