Warning: This function is
currently not documented; only the argument list is
available.
Warning: This function is
EXPERIMENTAL. The behaviour of this function, the
name of this function, and anything else documented about this
function may change without notice in a future release of PHP.
Use this function at your own risk.
Applies a color vector to each pixel in the image. The length of the vector
is 0 for black and white and at its maximum for the midtones. The vector
weighing function is f(x)=(1-(4.0*((x-0.5)*(x-0.5)))).
Return Values
Returns TRUE
on success.