The input images are several zmaps.
The resulting image 'result.v' displays outlines of the individual zmaps
thresholded at the given parameters '-pos' and '-neg'.
Each outline of a zmap
receives an individual code (code '1' for the first zmap, code '2' for the
second zmap, etc.).
The image 'result.v' can be visualized just like a zmap
using standard visualization tools (e.g. 'vlview','vlrender').
By using an appropriate color table in 'vlview', the grey codes can be
transformed into color codes.
If the parameter '-ref' is supplied, a 3D anatomical reference image is added to the output file.