are located at feature points around the sample points. For
example, in the cases of SCS and UKMS shown in Figs. 2 and 5, the
hollow triangle represents the ideal GCPs location in the reference
image, while the filled triangle represents the real GCPs location
after adjustment.
Using the framework of the simulation experiment discussed
in section 3.1, three sampling design for selecting GCPs (i.e., SRS,
SCS, and UKMS), the corresponding VP RMSE statistics (i.e., RMSEu,
RMSEv, RMSE) and the sum of the two square errors statistical inference
results (i.e., the mean, variance, t-value, lower confidence and
upper confidence of z) were calculated as listed in Table 1. In the
case of the SRS GCPs spatial sampling design (see Fig. 2a), the GCPs
were distributed randomly throughout the image. The RMSE and
the mean of z were 0.5413 and 0.2930, respectively, which were
the largest values among the three sampling design. In the case