Figure 9. Validation of the decomposition method based on the simulated data. Plot a) shows time series of endmembers E1
and E2. X1 and X2 are the simulated components which are fractions of the two endmembers with noises (random values
from -0.1 to 0.1). The simulated mixed pixel time series (y) is the sum of two components X1 and X2. The time series (y) is
decomposed based on E1 and E2 and compared to X1 and X2, as shown in plots b) and c). The solid lines in b) and c) are
1-to-1 lines, and the dashed lines are regression results.
Figure 10. Comparison between the fractional covers derived from the frequency decomposition approach and cover
measured from high-resolution images: (a) woody components comparison, (b) herbaceous components comparison. The
regression line with R
2
, and residual standard error are displayed. c) Linear relationship between the woody
NDVI
and
IKONOS
and Google Earth derived fractional cover compared to previous studies.
PHOTOGRAMMETRIC ENGINEERING & REMOTE SENSING
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