Title:A graphical operator framework for signature detection in hyperspectral
imagery
Abstract:Automated extraction of quantitative information via detection algorithms
from remotely sensed multi- & hyperspectral imagery requires one to have a
mathematical model for the "background" and "foreground" signatures in the
image. Given these data models, one can then make decisions per-pixel as to
the likelihood of the presence of a signature of interest. Traditional
processing schemes rely heavily on simple first and second order statistics
or linear subspace models of the data to make these decisions and have been
successful in several applications such as sub-pixel target detection and
anomaly detection. However, the new generation of sensors has a significant
improvement in spatial and spectral coverage and resolution. At these
improved spatial and spectral resolutions, the sensors image the surface of
the Earth at ever-greater levels of detail. It is simple to show that
assumptions of multivariate normality, or that the data are well-defined by
linear subspaces, are not well-met by the current generation of sensors.
Here we will present methods that derive from a graphical model of the image
data in the spectral domain. Non-linear dimensionality reduction methods
have been widely applied to hyperspectral imagery due to its structure as
the information can be mapped in a lower dimensional subspace. One of these
methods is Laplacian Eigenmaps (LE), which has been widely used in
clustering or automated classification. Schrodinger Eigenmaps (SE) has been
previously introduced as a semi-supervised classification scheme in order to
improve the classification performance by taking advantage of labeled data,
encoded in a potential term V. Here, we explore the idea of using SE in
target detection by varying V to include target signature label data.
Experimental results using different targets are shown.
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