Seafloor segmentation using angular backscatter responses obtained at sea with a forward-looking sonar system

Segmentation of the seabed is addressed by exploiting the local angular backscatter acoustic responses of the bottom. The study is based on data collected at sea with an experimental front-scan sonar system (COSMOS - Project partially funded by the European Commission in the MAST III program - Contract n° MAS3-CT97-0090 - DG12 - ESCY). Data were recorded during a three day survey in the Mediterranean Sea in high variability sediment areas. The front-looking geometry of the COSMOS system enables the collection of the local angular responses of the bottom over a wide range of incidence angles. The angular responses are projected on a principal components basis and subsequently classified by means of a density-based cluster identification method. The resulting segmentation maps delineate properly homogeneous zones of the seafloor that are in agreement with the ground-truth information provided by samples collected at sea.