LAUSR

ABSTRACT Recently, China has witnessed rapid development of high-resolution imaging satellites, with remote sensing images from satellites being applied extensively in social and economic sectors. The normalized difference built-up index (NDBI) was first used to extract urban built-up areas from TM/ETM+ image data. After successful launch of the Landsat-8 satellite, modifications have been made to the NDBI approach (BBIOLI approach) for mapping urban built-up areas from operational land imager (OLI) data with higher accuracy. However, experiments showed that the BBIOLI approach is not very suitable for Chinese high-resolution satellite image data. This study firstly analysed the spectral curves of ground objects generated by the GF-1 satellite and then proposes an innovative WE-NDBI approach to mapping urban built-up in the study area, i.e. large counties located in Xichang. The experimental results demonstrate an overall accuracy of 91.4%. To compare the WE-NDBI and BBIOLI approaches, the latter was used to extract urban built-up areas from OLI data for the same study area, and the experimental accuracy is 77.0%. It is concluded that the WE-NDBI approach is more suitable for mapping urban built-up areas.