Research On Road Traffic Monitoring Method Based On Aerial Image

The vehicle detection and tracking based on UAV aerial images has become a research hotspot in the field of intelligent transportation.It can provide effective,complete and accurate real-time traffic status information for urban traffic management and control.It can reduce traffic pressure,reduce traffic accidents and improve traffic Operational efficiency.However,there are many limitations based on the current monitoring systems.Firstly,the range of traditional road traffic monitoring is restricted to the sensor's distributions,such as induction loops,radar sensors and traffic cameras.According to the sparse distribution of the current traffic monitory system,there are many blind regions on a city road network.Secondly,most traffic sensors are designed to collect traffic information on a fixed road section or with a limited road length.As a result,it is convenient to obtain traffic data at lane's level,including each lane's average speed,density and flow,but it is hard to obtain traffic data at vehicle's level based on these discretely distributed sensors,such as vehicle's trajectory data.In order to solve the above two problems,this paper proposes a vehicle detection and tracking algorithm based on UAV aerial video..It is divided into three parts: aerial image road extraction,vehicle detection based on UAV video and vehicle tracking.The main contributions of this paper are as follows:(1)In order to solve the problem of disturbing external factors such as vehicles,buildings,shading,light,weather and so on in aerial image road detection,a road extraction algorithm composed by several methods was proposed.First,a image analysis technology was used to analyze the connectivity feature and width feature of road based on a color model.Then,the road pixels were extracted thought the method of Hough transform.Next,the intersection processing method was used to eliminate the noise in the image.At last,the road was extracted from the complex aerial images through the road shadow color analysis,noise classification processing and road renovation technology quickly and efficiently.(2)This paper introduces a new vehicle detecting and tracking system based on image data collected by UAV.This system uses consecutive frames to generate vehicle's dynamic information,such aspositions and velocities.Four major modules have been developed: image registration,image feature extraction,vehicle shape detecting,and vehicle tracking.Some unique features have been introduced into this system to customizethe vehicle and traffic flow and to jointly use them in multiple consecutive images to increase the system accuracy of detecting and tracking vehicles.Field tests demonstrate that the present system exhibits high accuracy in traffic information acquisition at different UAV altitudes with different view scopes,which can be used in future traffic monitoring and control in metropolitan areas.