Utilization of LiDAR and tidal gauge data for automaticextracting high and low tide lines
联合机载LiDAR数据和潮汐数据自动提取潮位线

First, a binary image containing only land and ocean pixels is generated by intersecting the LiDAR-derived shoredigital surface model (DSM) and the ocean surface derived from tidal gauge data at first. Then a series of image processing algorithmsare applied to extract preliminary high and low tide lines. Since LiDAR pulses can not penetrate into water, some regionsnear the low tide line may have invalid DSM values. In order to overcome this disadvantage, a mobile trend surface fitting methodis used to extrapolate the DSM near low water lines, hence more accurate low tide lines can be extracted. Experimental resultsshow that this method can extract high and low tide lines effectively with less manual labors.