ACQUIRING UNDERWATER DSM USING CLOSE-RANGE PHOTOGRAMMETRY

摘要

Underwater digital surface model (DSM), which is acquired by through water photogrammetry, is affected by light refraction so the resultant DSM is higher than its true value. Previous researches proposed correction procedures to mitigate this effect, but they show the tendency to over-correct the DSM. In this study, we propose a new correction procedure that based on the empirical relation between the DSM value determined from photogrammetry measurement and that obtained by a measuring probe. This new method is validated by comparing the DSMs of a small object acquired in exposed and underwater conditions.