Performance evaluation of different DEMs for topographic correction on LAPAN-A3: A preliminary results

摘要

Topographic correction over the mountainous region is an essential preprocessing step for landuse/landcover extractionfrom earth observation (EO) satellite data. Until the time of this paper writing, there has not been any publication regardingtopographic correction on LAPAN-A3 multispectral data. Topographic correction mainly grouped into two categories:band ratio and illumination modeling which required ancillary digital elevation model (DEM). This paper aims to evaluatethree different DEM sources used for topographic correction on LAPAN-A3. These DEMs are Shuttle Radar TopographicMission (SRTM), ALOS World 3D (AW3D), and nation-wide DEMNAS. The topographic corrections were performedover a subset of forested mountainous region in South Sulawesi, Indonesia. Minnaert correction algorithm was used in allthree DEMs and evaluate the results. Performance evaluation was based on visual assessment, as well as spectralhomogeneity of the pixel value before and after correction. The spectral homogeneity was calculated based on coefficientvariation changes before and after correction. The initial results showed that SRTM produced the best visual appearance,while AW3D 30 performed the best in terms of highest reduction in coefficient variation.