data.frame containing control point coordinates arranged
in four (4) columns: X source, Y source, X target, Y target.
parameters
A vector of six (6) parameters for representing the
transformation, namely: a, b, c, d, e and f, where
x' = ax + by + c
y' = dx + ey + f
Author
German Carrillo
Details
Both controlPoints and parameters are optional, but one has to be given. In
the case of the latter, the name of the argument has to be specified, e.g.,
AffineTransformation(parameters=c(1,2,3,4,5,6))