This module copies the color level\index{level line} recorded in the 
{\em input} {\tt Cmimage} to the {\em output} {\tt Cmimage}, 
but the ones with length (number of pixels) less than a given threshold. 
The length threshold ($10$ by default) can be changed using the option
\verb+-l+.

As this module is very similar to {\tt ll\_remove}, but acts on a 
color topographic map\index{topographic map!color} instead of a 
gray levels one, please read the documentation of {\tt ll\_remove}
to get the filter this function performs, and refer to {\tt cml\_decompose} 
and~\cite{coll.froment:topographic} to learn more about color level lines.
