Independent Component Analysis for Blind Unmixing of Hyperspectral Imagery With Additional Constraints

In recent years, independent component analysis (ICA) has been applied to unmix the hyperspectral data since it can perform without the prior knowledge of ground objects. The traditional ICA algorithm regards the extracted independent components as unmixing results, which is not reasonable for hyperspectral imagery, because different endmembers are not actually independent from each other. In order to solve this problem, a new approach, named as constrained ICA, is proposed, in which we consider “uncorrelation” instead of “independence.” Two constraints of the hyperspectral data (the abundance nonnegative and abundance sum-to-one constraints) are introduced to the ICA, changing its objective function based on independence assumption. Furthermore, we develop a technique, called as adaptive abundance modeling, to characterize the statistical distribution of the data. The model is automatically constructed according to the given data, which can encourage the algorithm that is applicable to various hyperspectral images with different statistical characteristics. The experimental results on both simulated and real hyperspectral data demonstrate that the proposed approach can obtain more accurate results with respect to existing algorithms. As an algorithm with no need of prior spectral knowledge, our method provides an effective solution for the blind unmixing of the hyperspectral data.