This module performs in-place a local zoom of order zero 
(pixel duplication) on a Cimage.
You may specify in $(center\_x,center\_y)$ 
the center of the local zoom (default
is $(256,256)$), and in $width$ the width of the zoomed box (default is 40).
The zoom factor is given by $factor$ (default is 2).
\index{zoom!of an image}

For an example of the use of this module, see the cview module.

