Creation of models for the measurement of marine species using along track video (ATV)

Scientists have often used video as a qualitative data source, allowing them to determine the macro-species composition and abundance. Quantitative information has also been collected from video, though less frequently, using Along Track Video (ATV) methods. ATV data is obtained by attaching a video camera to a stable platform that is then towed over the area of interest. The resultant video images must be linked to a spatial reference system, and can be used in much the same way as along track satellite imagery. With correct calibration, photogrammetric methods may be utilised to obtain measurements of the size and volume of benthic biota. An ATV system had been developed by the Commonwealth Scientific and Industrial Research Organisation (CSIRO) Division of Marine Research, Hobart, Australia. The imaging platform is a towed submersible sled (the Towed Automatically Compensating Optical System, or TACOS). This system has been used for towing both still and video cameras to capture forward looking oblique images at depths of up to 200 metres. In conjunction with other data, the CSIRO has used ATV in a study of continental shelf habitats that are considered vital for sustainable commercial fisheries. A continuous coverage of ATV data is obtained by extracting sequential frames from the video record. ATV, used in conjunction with other methods, may prove to be a useful tool in deeper ocean biological studies. It is not bound by the depth limitations of overhead optical remote sensing methods, or subject to the safety and stability problems facing divers, and has distinct advantages over still photography. Video data have been used to create a rectified mosaic of a section of the seafloor, which allowed the measurement of target species. This task involved the integration of spatial information with data from the video record.