A. Lorencs, I. Mednieks & J. Sinica-Sinavskis. Selection of informative hyperspectral band subsets based on entropy and correlation. International Journal of Remote Sensing, 39:20, pp. 6931-6948, 2018.
The article proposes two novel and relatively simple unsupervised procedures for the selection of informative small subsets of spectral bands in hyperspectral images. To ensure the informativeness of the subsets, bands featuring higher entropy are included. The correlation of band images is restricted to avoid redundancy of the subsets. The entropy multiple correlation ratio procedure employs the entropy-correlation ratio for the selection of spectral bands. The entropy-based correlated band grouping (ECBG) procedure divides the spectrum into groups of bands featuring highly correlated images. The subsets obtained were characterized by the performance of classifiers using only data from included bands. The ECBG procedure provided better results than the alternatives if the number of selected bands was low. Another advantage of this procedure is the possibility of averaging the images obtained for spectral bands within the groups found. It is shown that classification results are significantly improved if such an averaging is used. In the data acquisition practice, it can be used for a purposeful merging of spectral bands in the configuration of hyperspectral imagers, which allows one to reduce the amount of data to be saved in real time and thus helps one to improve the achievable spatial resolution.