Due to a spread of electronic toll collection system (ETC), drivers are at increased risk of accidents around booths of a tollway, such as a cross traffic between a vehicle with ETC and another vehicle. Thus, it is important to analyze a traffic flow around tollgates. In this paper, we propose a novel tracking method for vehicles which go through the tollgate using monitoring cameras installed at a roof of the tollgate. Using the proposed method, we perform experiments of a traffic flow analysis in several tollgates, and investigate an influence of the number and the location of booths, which are different in each tollgate, on the traffic flow around the tollgate.%ITSにおけるマシンビジョン技術と従来の諸研究を概観すると，これまでの環境センシングは，超音波やミリ波レーダのようなセンサを用いて交通流量の計測や危険車両の検知など多くの局面で実用化されてきたが，検知範囲は局所的であり，得られる情報量が乏しいという欠点がある.一方，カメラを用いるマシンビジョンでは検知範囲が非常に広く情報量に富むため複雑な交通状態の詳細な解析に有効であると期待されている.
展开▼
