Ground object identification-based on absorption-band position using EO-1 hyperion data

Abstract

In order to accurately identify ground objects in the hyperspectral imagery by spectral matching, it is important to analyze the absorption-band parameters. This paper presents a new spectral matching method which is based mainly on analysis of the absorption-band position. A measured spectrum of a ground object can be subject to shifts from its real wavelength position; meanwhile an absorption band in the spectrum can also be shifted relatively. Both these shifts are due to the environmental effects. Our spectral matching method stresses the quantification of the total shift of the absorption-band position, thus to get a possible offset range of the measured absorption bands. This offset range is taken as a constraint on the matching process. The pixel spectrum in the image is then compared to each known reference spectrum in a spectral library previously built, so that the ground object corresponding to the reference spectrum is identified. A case study is conducted in Pulang Porphyry Copper deposit, Zhongdian county, Yunnan, China. Five types of ground objects were studied and it is shown that our methods can get more accurate identification results than the approach which does not consider the shift ranges.