All digital change detection is affected by spatial, spectral, temporal, and thematic constraints.
The type of method implemented can profoundly affect the qualitative and quantitative estimates of the
disturbance (Colwell & Weber, 1981). Even in the same environment, different approaches may yield
different change maps. The selection of the appropriate method therefore takes on considerable
significance. Most digital change detection methods are based on per-pixel classifiers and change
information contained in the spectral-radiometric domain of the images. They combine both the
procedures for change extraction (change detection algorithm) and those for change separation/labeling
(change classification routine)