Design and Initial Evaluation of Acoustic Vehicle Count System utilizing Dynamic Time Warping

Vehicle counting is one of the fundamental tasks in the intelligent transportation systems (ITS). Although automatic vehicle counters have been proposed to retrieve realtime traffic data, current automatic vehicle counters are suffered from high deployment costs, resulting in limited number of deployments. In this paper, we present a vehicle counter using sidewalk microphones that are easily deployed at a low cost. Our vehicle counter only relies on two microphones and counts vehicles using sound map, which is a timedifference map of vehicle sound on the two microphones. We developed a vehicle count algorithm using sound map. Our vehicle count algorithm performs template matching utilizing dynamic time warping (DTW) to adapt to vehicle speed variation. We herein describe the design and implementation of our vehicle count system. Experimental evaluations reveal that our vehicle count system successfully counted vehicles with a precision of 0.92.