System for maritime surveillance aid

A system to aid maritime surveillance is being studied to search for small floating objects like a life raft or to detect oil spill more reliably and efficiently. The system consists of sensors, an image processor and a display so as to reject unnecessary noise in the sea surface images, and then to detect and identify the objects to be searched. This paper describes the optical sensor system with an infrared camera and a TV camera. The infrared camera detects 3-5 micrometers waveband by 512 by 512 solid state sensing elements. The systems was used to gather images on different sea areas in summer and winter by aircraft and on the ground. Typical images are presented to demonstrate the validity of the sensor system to search for small flowing objects. The influences of air and water temperature, weather and observation altitude upon the images are discussed. Image processing techniques like filtering or image superposition are also described to suppress noise.