Using polynomials 
t and (1-t)
to transition between two things -- 
even images!
MAT329
Andy Long

image1=Import["http://ceadserv1.nku.edu/longa//classes/mat225/days/Rosemanie-with-her-Mohawk.jpg"];
image2=Import["http://ceadserv1.nku.edu/longa//classes/mat225/days/RoseBlur.jpg"];
{image1,image2}

image[t_]:=ImageAdd[ImageMultiply[image1,(1-t)],ImageMultiply[image2,t]]
{image[0],
image[.5],
image[1]}

Animate[image[t],{t,0,1},AnimationRunning->False]

image3=Import["http://ceadserv1.nku.edu/longa//classes/mat225/days/RoseUpsideDown.jpg"];

imageblend[t_]:=ImageAdd[ImageMultiply[image1,(1-t)],ImageMultiply[image3,t]]
Animate[imageblend[t],{t,0,1},AnimationRunning->False]