STUDY ON A SMALL-SCALE TERRACED TERRAIN EXTRACTION METHOD USING WAVELET ANALYSIS MAP

Abstract

 Microtopographic and topographic maps produced from aerial laser survey data are increasingly used for commercial purposes. Unlike slope gradient maps, wavelet analysis maps can extract terrain steps without being affected by slope inclinations. First of all, we created a simulated terrain with varying slopes and specific height differences to examine those height differences that can be represented by wavelet analysis and slope gradient maps. Then we examined the height differences that can be extracted from the wavelet analysis and slope gradient maps for an average slope of approximately 40°, including the rockfall source, using the results of the field survey. The height difference that could be extracted from the wavelet analysis maps was approximately 2 m, whereas the difference that could be extracted from the slope gradient maps was 4 m or more. Therefore, wavelet analysis maps are better in extracting small height differences compared to slope gradient maps.