Sea trials of a computer vision based fish species sorting and size grading machine

A prototype machine is described for sorting fish by species and size at sea. The fish are transported along a conveyor underneath a video camera whose images are processed by a computer to obtain shape and colour descriptors. The fish are then diverted into the appropriate bin using computer controlled pneumatic arms. Species sorting accuracies at both Rockall and the North Sea of 99% were achieved for flatfish and round fish at a throughput of 40 fish/min.