Image Analysis, Classification and Change Detection in Remote Sensing, 3rd Edition

384 Change Detection

9.4.3 Scale invariance

An additional advantage of the MAD procedure stems from the fact

that the

calculations involved are invariant under linear and affine transformations of

the original image intensities. This implies insensitivity to linea r differences

in atmospheric conditions or sensor calibrations at the two acquisition times.

Scale invariance also offers the possibility of using the MAD transformation

to perform relative radiometr ic normalization of multi-temporal imagery in a

fully automatic way, as will be explaine d in Section 9.8 below.

We can illustrate the invariance as follows. Suppose the second ima ge G

2

is transformed ...