Detecting the adjacency effect in hyperspectral imagery with spectral unmixing techniques
Faculty of Sciences. Physics
New York (N.Y.) :IEEE
Engineering sciences. Technology
IEEE journal of selected topics in applied earth observation and remote sensing / IEEE geoscience and remote sensing society; IEEE committee on earth observations. - New York (N.Y.)
, p. 1070-1078
University of Antwerp
The adjacency effect is an interesting phenomenon characterized by the occurrence of path interferences between the reflectances coming from different ground-cover materials. The effect is caused by atmospheric scattering, hence a typical approach to its detection has been the modeling of radiation transfer and spectral correspondence at particular wavelengths. In this paper, we investigate the detection of adjacency effects as being a general unmixing problem. This means that we opt to use spectral unmixing to separate the true signature of a pixel from the background scatter reflected from its adjacent neighborhood. To account for different types of atmospheric scattering, we consider several unmixing methods. These include the established linear- and a recently studied generalized bilinear model, as well as a more data-driven unmixing that could implicitly address nonlinearities not covered by the first mentioned approaches. We evaluate these unmixing models by comparing their results with those obtained from a specialized treatment of the adjacency effect in turbid waters surrounded by vegetated land. This comparison is demonstrated on real data acquired under varying atmospheric conditions.