Hyperspectral Data Processing: Algorithm Design and Analysis

17.5 Real-Image Experiments

The HYDICE image scene in Figure 1.15 was chosen for real-image experiments because the ground truth of 15 panels specified by 19 R pixels is completely available for LSMA performance evaluation. Nevertheless, this ground truth should be only used to serve a reference since the scene is real data where uncharacterized spectral variations may affect the performance. Specifically, those pixels that are identified by a ground crew as panel center pixels may not actually pure pixels as demonstrated by Chang et al. (2004) and will be also shown in the following experiments. These experiments indicate that the prior knowledge may not be as reliable as it is supposed to be.

17.5.1 LS-ULSMA

First of all, the VD estimated for this scene, n_VD, is 9 with the false alarm probability . Figure 17.12(a) shows the 9 target VSs that were extracted directly from the original data by the ATGP and were considered as a set of BKG VSs that included three panel pixels from rows 1, 3, and 5. Figure 17.12(b) shows the 9 target VSs extracted from the sphered data by ATGP that included five panel panels extracted from each of five rows and were considered as a set of target VSs,