TOWARDS CONSTRUCTION OF SPECTRAL LIBRARY OF URBAN SURFACE MATERIALS BASED ON SPECTROSCOPY

Urban areas contains complex and high diversity of built-up and non built-up materials, involves horizontal and inclined surfaces like roads and roofs. For this purpose, spectra of the main urban surfaces (i.e. roofs and pavement materials) should be measured. Spectra acquired from an imaging platform, field and laboratory. In this study field spectra have been acquired directly using an ASD field 3 spectrometer instrument. Also, Spectra measurements of urban surface materials have been measured in the laboratory for small samples brought from field represented urban surface using two spectral comers VINIR Visible Near Infrared and Short Wave Infrared SWIR. Also, spectra have been acquired from satellite and airborne sensors; Landsat Enhanced Thematic Mapper ETM+ , Hyperion Earth Observing EO-1 and Hyspex camera. The selected study area located in Cairo, Egypt has a complex urban land use / Land cover LU / LC. The main objective is to develop, spectral library from imaging system, field and laboratory measurements. Spectral library proposed to be used for calibrating and validating hyperspectral data and for the purpose of accurate detection surface materials and improve results of classification of urban surfaces. The methodology involves divided urban surfaces into two main classes built up and un-built up areas. Each main class has been divided into sub classes according to materials, taken into consideration cowmen materials. After that develop sample strategies, measurements in situ, processing and construct a spectral library. The results show that there was considerable spectral confusion between urban land cover types (i.e. specific roof and road types). Construction complete spectral libarary for any country is very essential for many remote sensing applications but it is hard task and very expensive and timely.