These signatures encompass the contributions of all the materials in the training set. The result is a signature that is representative of a specific material or set of materials. Upon deriving a signature, conventional classifiers identify pixels in the scene that have the same spectral properties as the signature. A detection occurs when the difference between the residual spectrum and the signature falls within a set of tolerances. It provides a higher level of discrimination for most applications.
Traditional classifiers attempt to include all materials in the pixels.
Environmental Correction Generates a set of scene-specific environmental correction factors to compensate for variations in atmospheric and environmental conditions. This unique step allows signature portability to other scenes collected at different dates and places. Signature Derivation Allows the user to specify a training set and then derives the material of interest by extracting the spectral component that is most common. The material of interest can either be whole-pixel or subpixel in the training pixels. Classification Removes background materials and compares residual spectra to the reference signature.