The underwater digital terrain model (DTM) is important in characterizing water-submerged zones If the DTM is generated by photogrammetry the effects of refraction at the air/water interface cause the depth-dependent bias in the underwater DTM The empirical method was used in this study to obtain the correction function based on the regression relation between the elevations of the river bed determined from the aerial image and that obtained from in-situ measurement This study used a medium frame camera with the pixel size of 6 8 μm and a ground resolution of 3 cm to acquire the high resolution color aerial imagery in northern Taiwan The position and orientation of the camera exposure position was determined by the onboard global positioning system and inertial measurement unit The SOCET GXP software was used to perform aerial triangulation Results were compared with the in-situ measurements obtained by the total station surveying The underwater DTM with refraction correction of the empirical method has the accuracy about 0 2 m and no evident bias
Acquiring Underwater DTM Using Aerial Imagery
可芹, 洪. (Author). 2014 6月 13
學生論文: Master's Thesis