Patent ID: 9213913
Filing Date: 2015-12-15
Classification: G06F,G06K,G06T

Abstract:
1. A method for detecting a target in a scene pixel of a hyperspectral scene, the target having a spectrum similar to a known spectral reference, the method comprising: in a target detector provided with hyperspectral imaging data for a plurality of scene pixels of a hyperspectral scene and one or more spectral references each corresponding to a target, wherein the hyperspectral imaging data being provided from a hyperspectral sensor and a given spectral references includes a full set of terms representing spectrum whitened by transforming the spectrum using a spectral covariance of the hyperspectral scene, and wherein each term is indexed by an eigenvector and eigenvalue of the spectral covariance used to calculate that term: for a given spectral reference: with respect to the given spectral reference, for each scene pixel in the plurality of scene pixels: comparing the intermediate target score to a threshold; identifying scene pixels having intermediate target scores less than the threshold as empty scene pixels that do not include targets; if a number of empty scene pixels is less than a specified fraction of a total number of scene pixels and a number of intermediate target scores computed is less than a counter, then: for each scene pixel remaining in the plurality of scene pixels, computing an updated intermediate target score using the updated target score equation; comparing the updated intermediate target scores to an updated threshold, the updated threshold being greater in value than the threshold; identifying scene pixels having updated intermediate target scores less than the updated threshold as empty scene pixels that do not include targets; if the number of empty scene pixels is greater than or equal to the specified fraction of the total number of scene pixels or the number of intermediate target scores computed is greater than or equal to the counter, for each scene pixel remaining in the plurality of scene pixels, computing a full dimension target score based on a full dimension target score equation including a full set of terms; and declaring which scene pixels include targets corresponding to the given spectral reference based on comparisons of the computed full dimension target score to a full dimension target score threshold, the full dimension target score threshold being greater in value than the threshold and the updated threshold.