Spectral angle mapper classification and vegetation indices analysis for winter cover monitoring using JERS-1 OPS data

Low solar elevations cause strong shadow effects in mountainous terrain. In order to examine the effect of bidirectional reflection on the reflected radiance response of the JERS-1 OPS bands, the NDVI and TVI were analyzed for differential shading. These geometric illumination conditions hinder accurate land use classification. This paper shows how the effects of differential shading on the classification of vegetation could be reduced through the use of the Spectral Angle Mapper (SAM) algorithm. This method proved better than layered classification logic or rule-based expert systems and fuzzy classification with nonparametric priors. The spectral angle mapper classification method produced seven land cover classes in the lower Nakdong River region : forest, urban, winter agricultural area, reed vegetation, barren(rock and sands), river (freshwater) and sea (salt water), and an unclassified category which indicated shadow areas in the mountainous forests