Road traffic island extraction from high resolution aerial imagery using active contours

Traffic islands are important features of mapped road networks in topographic databases. The modelling of these, however, is generally not explicit in most approaches to road extraction from aerial imagery. Traffic islands can be considered as elements of road junctions and in this paper an active contourbased approach is proposed for their automatic extraction. The road junction outline and vector data is first provided so attention can be focussed on specific locations. In order to distinguish traffic islands from other features such as cars, constraints are introduced. A brief review of the active contour model adopted is first presented, after which the traffic island extraction approach is described. An account is then given of experimental testing of the developed method, which utilised aerial images of 0.1 m ground resolution, over both suburban and rural areas. Experimental results are presented and prospects for the new approach are discussed.