Hyperspectral Unmixing With Endmember Variability via Alternating Angle Minimization


In hyperspectral unmixing applications, one typically assumes that a single spectrum exists for every endmember. In many scenarios, this is not the case, and one requires a set or a distribution of spectra to represent an endmember or class. This inherent spectral variability can pose severe difficulties in classical unmixing approaches. In this paper, we present a new algorithm for dealing with endmember variability in spectral unmixing, based on the geometrical interpretation of the resulting unmixing problem, and an alternating optimization approach. This alternating angle minimization algorithm uses sets of spectra to represent the variability present in each class, and attempts to identify the subset of endmembers which produce the smallest reconstruction error. The algorithm is analogous to the popular multiple endmember spectral mixture analysis technique, but has a much more favorable computational complexity, whileproducing similar results. We illustrate the algorithm on severalartificial and real data sets, and compare with several other recent techniques for dealing with endmember variability.




R. Heylen, A. Zare, P. Gader, and P. Scheunders, “Hyperspectral Unmixing With Endmember Variability via Alternating Angle Minimization,” IEEE Trans. Geosci. Remote Sens., vol. 54, iss. 8, pp. 4983-4993, 2016. 
author = {Rob Heylen and Alina Zare and Paul Gader and Paul Scheunders},
title = {Hyperspectral Unmixing With Endmember Variability via Alternating Angle Minimization},
journal = {IEEE Trans. Geosci. Remote Sens.},
year = {2016},
volume = {54},
number = {8},
pages = {4983-4993},
month = {Aug.},
doi = {10.1109/TGRS.2016.2554160},