Using an active contour method to detect bilge dumps from SAR imagery

An automatic approach to detect bilge dumping in synthetic aperture radar (SAR) images over Southern African oceans is proposed. The approach uses a threshold-based algorithm and a region-based active contour model (ACM) algorithm to achieve an efficient bilge dump detection tool. A threshold method was used to detect areas with a high bilge dump probability while the ACM method is used to get closed contours of potential bilge dumps. A discrimination step was implemented to detect linear features as potential bilge dump events. The automated approach was investigated using SENTINEL-1A and ENVISAT Advanced Synthetic Aperture Radar (ASAR) where the proposed approach showed promising results.