An improved spectral knowledge for multi-temporal images classification-a case study of urban area

The authors demonstrate that the normalized reflectance is much more suitable than bidirectional reflectance factor (BRF) as the scene-independent spectral knowledge as Wharton (1987) suggested. Normalized reflectance can be obtained from normalization of BRF by its intrinsic BRDF. Transformed divergences of apparent reflectance, BRF and normalized reflectance of the urban target in the multi-temporal dataset are compared.