結合空載LiDAR與彩色航照應用於崩塌地研判

Integrating Airborne LiDAR and Color Aerial Photography for Landslide Interpretation

10.6574/JPRS.2010.15(1).8

劉治中(Chi-Chung Lau)；蕭國鑫(Kuo-Hsin Hsiao)；饒見有(Jiann-Yeou Rau)；劉進金(Jin-King Liu)；吳哲榮(Jer-Rong Wu)；黃群修(Qun-Xiu Huang)

崩塌地 ； 數值高程資料 ； 空載光達 ； Landslides ； Digital Terrain Model DTM ； LiDAR

航測及遙測學刊

15卷1期（2010 / 03 / 01）

111 - 122

繁體中文

本研究結合彩色航照與空載光達資料，藉由半自動化方式辨識崩塌地，並利用三維立體展示的人機操作介面，供人工判釋及編輯崩塌地邊界向量資料。其中彩色航照利用綠度指數，空載光達資料則利用數值高程模型(DEM)與數值地表模型(DSM)，除計算地物高度模型(OHM)與坡度資料外，亦結合地表粗糙度(Roughness)來確定崩塌地範圍。初步成果顯示利用上述參數，依訓練樣區統計資料選定適當之門檻值後，可有效地偵測出局部範圍的崩塌區位置；對於誤判的地區，藉由開發的三維立體編修系統，可以透過人工進行必要之修正。另配合崩塌地完整屬性需求，亦設計了及時研判功能，並依崩塌地發生之位置、形狀、滑動面型態及崩塌方式等，建置崩塌地的地質屬性，提供後續之規劃參考用。

In this study, a semi-automatic landslide classification method is proposed and implemented using both airborne LiDAR data and color aerial photographs. A man-machine interface is implemented with three-dimensional perspective display capability, thus to ease the manual interpretation and editing after a preliminary result of landslide polygons are generated by an automatic algorithm proposed in this study. Four parameters are used in the automatic algorithm, namely Greenness, Slope, OHM and Roughness. Greenness is derived from color aerial photograph and employed to define non-vegetated land of fresh scars of shallow-seated landslides. All the other tree parameters are derived from LiDAR DSM and DEM to portray the geomorphometric characteristics of landslides. Thresholds are derived automatically from training areas and then are applied in real time to show the distribution of possible landslides. With the 3D interactive interface, the possible landslides are draped on 3D perspective landscape on the screen. This is convenient to assist the human expert to further modify the results by deleting erroneous ones or modify the boundaries of landslides visually. In addition, the interface system can go without the semi-automatic approach and just be used for visual interpretation solely on basis of the expert knowledge of feature locations, shapes, and types of landslides. Attribute table linked with the landslide spatial feature can also be established in this system. It is proved in this study that this is a practical and efficient system.