A method for detecting and mapping Urban Area by ALOS/PALSAR data

TitleA method for detecting and mapping Urban Area by ALOS/PALSAR data
Publication TypeConference Proceedings
Year of Conference2010
AuthorsItabashi, K, Miyazaki, H, Iwao, K, Nakamura, K, Shibasaki, R
Conference Name31st Asian Conference on Remote Sensing
Date Published2010
Conference LocationHanoi, Vietnam
KeywordsALOS PALSAR urban extent map high resolution
Abstract

Currently, global urban extent map of high accuracy and resolution have been constructed mainly using optical sensor including ASTER/VNIR. However, there are some regions where urban area is not detected because of cloud cover and similar reflectance among land cover classes. In the present work, by using ALOS/PALSAR, a microwave sensor, we proposed a method for detecting urban area which cannot be detected by ASTER/VNIR optical sensor and developing urban extent map in high accuracy and resolution. We mainly used satellite images taken by Fine Resolution Mode of ALOS/PALSAR. Local-incident-angle corrected images by Fine Resolution Mode were used for this method. The proposed method consists of sampling pixel values and ground truth data at urban and non-urban area from ALOS/PALSAR images; constructing classifier based on the pixel values and ground truth data; and classifying pixels into urban or non-urban area. We compared the results with urban extent map derived from ASTER/VNIR optical sensor images, and evaluated the possibility of using ALOS/PALSAR data for developing urban extent map. In addition, we examined accuracy improvement of detecting urban area using both ASTER/VNIR and ALOS/PALSAR images. The proposed method could classify regions which were misclassified by ASTER/VNIR optical sensor images, and develop urban extent map in high accuracy and resolution.