Topographic Normalization of Formosat2-MS Images of Forest in Rugged Terrain: Using The Modification of Variable Empirical Coefficient Algorithm

• Main Author: 田應平
• Other Authors: 張國楨
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/91885528529703552411

碩士 === 國立臺灣師範大學 === 地理學系 === 98 === Topographic correction is a very important approach of pre-process in the remote sensing application in rugged terrain. Without this step, the quantification and classification of the image will be influenced. A new topographic correction approach, the Modification of Variable Empirical Coefficient Algorithm (MVECA), was developed on the theoretical and statistic analysis of the spectral values of remotely sensed data acquired from the rugged terrain and topographic variables. To prove the approach is practical, The approach was explained and analyzed in comparison with that before topographic correction and other approaches. The test site selected for the study is located on the relatively rugged terrain over the southeastern hill of the Yu Shan Mountain in Taiwan, the remotely sensed data utilized for examining the result of the proposed approach MVECA is Formosat2 image acquired over the test site. Visual comparison, statistical analysis, and the classification of corrected image are adopted for feasible evaluation of the proposed algorithm, and the results suggest that the proposed approach MVECA is capable for removing the topographic effects contained in Formosat2 MS image. The result also shows that MVECA has better ability of topographic correction than SCS+C and Minnaert+SCS in the area of the shadowed area and the steep terrain where incidesnt angles may approach 90°.