The Offshore Oil and Gas Industry in the North Sea has many requirements for three- dimensional measurements in air and underwater. A market audit found that use of conventional photogrammetry was being rejected for many applications because the information was not available fast enough. A development project was set up to replace the photographic cameras with a choice of video or high resolution digital electronic cameras, and the analysis system with a personal computer based image processing system. This solution is now in operation. The paper details the in-house development of the high resolution digital electronic camera and the personal computer based measurement hardware and software. It includes a discussion of the technological parameters, including the method for pixel for pixel correlation within the digital system, camera calibration techniques, the system algorithms, sub-pixel measurement and dimensional accuracy. It introduces the work that was carried out to make the final product acceptable to structural engineers, who now use it to transfer three- dimensional measurements to their CAD systems. It also looks at the work that is being carried out to transform the system into a closed loop control system for underwater robotic manipulators, which includes binary conversion, convolution filtering and tracking functions.
"Development of an operational digital photogrammetric system for the North Sea oil and gas industry", Proc. SPIE 1820, Videometrics, (24 February 1993); doi: 10.1117/12.141376; https://doi.org/10.1117/12.141376