Let $U$ be the input image, $(x_0,y_0)$ the input coordinates and
$a,b$ the minimum and maximum values.
The module computes the connected component of the following morpho-set $S$, such
that the point $(x_0,y_0)$ belongs to it:
\[
S = \{ (x,y) / a \leq U(x,y) \leq b \}
\]
More precisely, the module returns the area (computed as the number of pixels)
associated to the connected component of $S$.
By default, the 4-connexity is considered. Use the option  \verb+-c+ 
to get the 8-connexity.

If the option \verb+-o+ is selected, the connected component is copied into
the output image $O$.
The option \verb+-s+ allows to stop the computation when the given area
is reached.
