This abstract class defines a lookup table object. ByteLookupTable
and ShortLookupTable are subclasses, which
contain byte and short data, respectively. A lookup table
contains data arrays for one or more bands (or components) of an image
(for example, separate arrays for R, G, and B),
and it contains an offset which will be subtracted from the
input values before indexing into the arrays. This allows an array
smaller than the native data size to be provided for a
constrained input. If there is only one array in the lookup
table, it will be applied to all bands. All arrays must be the
same size.