Mixed-pixel decomposition of a hyperspectral image
is developed on the basis of extracting unique constituent elements
known as endmembers (EMs) and their abundance fraction
estimation. Recently, integration of spatial content and spectral
information is applied by means of several preprocessing modules
(PPs) with the purpose of improving EMextraction (EE) accuracy
and decreasing EE time. In this letter, a fast spatial–spectral
preprocessing module is proposed, which determines the spectral
purity score of pixels located at spatially homogenous regions.
These homogenous regions including not spatial border pixels are
identified using unsupervised k-means clustering technique and
spatial neighborhood system. Afterward, a fraction of homogenous
pixels (usually half) with greater spectral purity score is
adopted as the best EM candidates for subsequent EEs. This novel
PP is examined on synthetic and real AVIRIS data sets, which
demonstrates its worthy performance in terms of accuracy and
fast computation time.