Patent ID: 6665438
Filing Date: 2003-12-16
Classification: G06K

Abstract:
A method for hyperspectral imagery exploitation and pixel spectral unmixing, comprising the steps of:(a) receiving a hyperspectral image cube from a hyperspectral imaging sensor, wherein said hyperspectral image cube represents a scene in terms of wavelength and spatial position; (b) performing an image registration from band to band in an image registration module, wherein said image registration is a process of making one band image transforming to another band image without involving a map coordinate system transformation, so as to assure a physical position corresponding to one pixel in one band image coinciding with that in another band image; (c) sending said hyperspectral image cube registered in said image registration module to an atmospheric compensation module for compensating atmosphere effects in said atmospheric compensation module; and (d) unmixing hyperpsectral imagery data using genetic algorithm and robust Kalman filtering techniques, in a pixel by pixel fashion, until said hyperspectral image cube is completed, wherein the step (d) further comprises the steps of: (d-1) receiving spectral signatures of material of interest from a spectral library, and preprocessing said spectral signatures in a signature preprocessing module, wherein said spectral signatures from said spectral library are orthonormalized in said signature preprocessing module, so as to produce a decomposition of feature space into a collection of orthonormal signatures; (d-2) receiving said orthogonal signatures from said signature preprocessing module and a set of measurement data for a first pixel from said atmospheric compensation module by a first pixel abundance estimation module, and calculating an abundance estimation for said first pixel, wherein for pixel except from said first pixel, said first pixel abundance estimation module just bypasses said measurement data from said atmospheric compensation module; (d-3) receiving said orthogonal signatures from said signature preprocessing module and said measurement data for current pixel from said atmospheric compensation module, and said abundance estimate for said first pixel from said first pixel abundance estimation module by a Kalman filter, and performing spectral unmixing for said current pixel using Kalman filtering technique, wherein said abundance estimation for said first pixel is used as initial value for said Kalman filter which outputs an abundance estimation for said current pixel; (d-4) receiving said orthogonal signatures from said signature preprocessing module and said measurement data for said current pixel from said atmospheric compensation module, and said abundance estimation for said current pixel from said Kalman filter by a genetic algorithm unmixing module, and performing accurate spectral unmixing for said current pixel using said genetic algorithm to derive an accurate abundance estimation; (d-5) going to a next pixel, and receiving said orthogonal signatures from said signature preprocessing module and said measurement data for said current pixel from said atmospheric compensation module, and said accurate abundance estimate for the previous pixel from said genetic algorithm unmixing module by said Kalman filter, and performing spectral unmixing for said current pixel using Kalman filtering technique; and (d-6) going back to step (d-4) and iterating steps (d-4) and (d-5) until pixel ends in said hyperspectral image cube.