Hi there,

I've got a problem, which need to solve the derivative of affine transformation.

For example, a 2D affine transform is:

A_T(f_{x,y})=\left( \begin{array}{ccc}<br />
a_{11} & a_{12} & a_{13} \\<br />
a_{21} & a_{22} & a_{23} \\<br />
0 & 0 & 1 \end{array} \right)<br />
\left( \begin{array}{c}<br />
x \\<br />
y \\<br />
1 \end{array} \right)=<br />
\left( \begin{array}{c}<br />
x^' \\<br />
y^' \\<br />
1 \end{array} \right)

Here we got a_{ij}, which are 6 affine parameters. Then if we want to get the partial derivative of each parameter a_{ij}, which is:

\frac{\partial A_T}{\partial a}

May I ask how to solve the equation above please? Thanks.