Image registration: statement of the problem

left:$u_1$                                                                                  right:$u_2= u_1\circ A$

$A:\mathbb {R}^2\rightarrow\mathbb {R}^2$

Find $A$. $A = A(p_1,\dots, p_k)$, estimate the $p_i$.
 

Summer School on Mathematical Problems in Image Processing, Trieste, Italy, September 4th-18th 2000