Path Center Correction
1) Group of points: $\{ (x_{i},y_{i})\}_{i=1..n}$

2) Centroid of the group of points: $\left(\frac{1}{n} \sum^{n}_{i=1}x_{i},\frac{1}{n}\sum^{n}_{i=1}y_{i} \right)$.

3) Center of the image: $(x_{c},y_{c})$

4) Translation of arbitrary point $(x,y)$ to the center $(x_{c},y_{c})$: $t(x,y)=(x_{c}-x,y_{c}-y)$

Note that $(x,y)+t(x,y) = (x_{c},y_{c})$ ...

Now just substitute 2) in 4) and you have your formula to translate the centroid to the image center. Right?

I am sure that I am missing something here - the translation distance obviously cannot be kept the same for all points. Didn't you mean another type of transform (maybe scaling have to be included as well) ?