基於影像式事件偵測技術應用於PTZ攝影機

Abstract

本研究目的是利用影像處理技術來實現交通監控系統。系統由四大單元所構成，分別是「自動背景取得與更新」、「車輛偵測及追蹤」、「事件偵測」及「PTZ攝影機控制」。透過自動背景取得與更新單元，系統可以在車流影像中分析出背景並在長時運轉下更新背景，使背景會隨著天色改變隨之更新，保持車輛偵測的正確性；利用車輛偵測及追蹤單元進行交通影像分析，不僅可以獲得佔有率與交通流量等資訊外，還可以應用於事件偵測單元以偵測出異常停止車輛、車輛壅塞、逆行車輛、行人違規闖入與散落物等事件的發生；系統在事件發生同時會透過PTZ攝影機控制模組，命令PTZ攝影機轉至定位並放大合適倍率，提供較清楚之影像，如違規停止車事件，由事件偵測模組將事件由畫面中定位，再經由PTZ攝影機控制模組計算轉換出控制命令，使攝影機移至定位並完成拍照動作，可做為交通執法人員取締之影像，節省相當多的人力，一般交通錄影取締是藉由全時錄影，再經由人工瀏覽錄影畫面把違規之車輛挑選出來，本研究以自動化技術實現違規取締，不僅節省人力亦可提高效率。

The goal of this study is using image processing technologies to implement the traffic monitoring system. The system is composed of four units which are background image extraction and update unit (BEUU), vehicle detection and tracking unit (VDTU), incident detection unit (IDU) and PTZ camera control unit (PTZCU). The system gets an accurate background image and updates it by BEUU despite of vehicle passing through and weather changing.; The information provided by VDTU contain not only the traffic parameters but also the trajectories of the vehicles. IDU will reference the given information to detect incidents such as stopped vehicles, degree of traffic congestion, Wrong Way, Pedestrian Detection and Debris Detection. Meanwhile, PTZCU converts a control command with the position provided by IDU. PTZ camera will move to a suitable position, and get a clear image. Such as a stopped vehicle is detected by IDU, and IDU calculates a position of the vehicle. PTZCU converts the position to a control command. Next, the PTZ camera moves to the exact potion and take a picture. The picture can be an evidence for traffic enforcement officer. It can save much manpower. In usual, traffic enforcement officers find out traffic violations 一by full-time recording of enforce camera. It will save manpower and Improve efficiency with the automatic technique.