Image Processing, Video Image Coordinate Transformation And Wave Run-up

Nearshore measurement is an important content of ocean observation.The main measurement items are the nearshore hydrological parameters, such as wave,wave run-up,wave breaking and so on.Traditional equipments for nearshore measurement have a very high cost, their installation and maintenance are also very difficult. Nearshore video measurement is a simple method and has a low cost,just need to install some cameras. Some nearshore hydrological parameters are extracted from the nearshore video images shooted by some cameras.Nearshore video measures the hydrological parameters using remote sensing method,so it will not affect the normal operation of the ocean engineering.In order to achieve the purpose of nearshore video measurement, some calibration points need to be installed in the scene area, the corresponding relations between the object and its image is solved based on the location information from these calibration points,and then the nearshore hydrological parameters are measured by the corresponding relations and the knowledge in other fields.The main content of this paper as follows:1.It briefly introduces nearshore video measurement method and wave run-up's video measurement method.2. It describes DLT's principle and algorithm.3. It describes a space line's correction and measurement principle according to DLT algorithm and calibration points.4. It introduces a space plane's correction algorithm with calibration points and an error removing method for calibration points by RANSAC.At the same time, a space plane correction algorithm without calibration points is given.5. In this paper,a wave run-up's time stack image is established by a period of nearshore wave video, and an algorithm called least cost path of pixels value's sum is given to extract wave run-up's up edge.In the paper, the technologies of nearshore video measurement and wave run-up's video measurement are studied.Some algorithms such as the correction algorithm of a space line, the correction algorithm of a space plane and the solving algorithm of wave run-up's up edge are proposed in this paper. Some related programs's codes are made and the foundation is laied for a further study of nearshore video measurement.