Segmentation dirigée d'image sonar: application à la détection des stocks d'huîtres et de crépidules en baie de Quiberon

This study is inserted within the research project Risco, which aims at understanding the causes of oysters mortalities in the bay of Quiberon, since 2006. The objective was to test the feasability of an automatic segmentation of sonar images devoted to the distinction of molluscs (oysters and crepidulas) and sedimentary substrate. The method tested was of the type "segmentation dirigée basée région", implemented on the software SonarScope. It could be applied successfully only on muddy sediment where it succeeded to identify the shellfish sectors with negligeable error. However the distinction between oysters and crepidulas proved to be very delicate. A generalization to other sectors of the bay will be attempted.