AimsSelectGradPoints
    --------------------

Select a given number of points from a volume with higher probability with
higher gradient norm.

Options :

--input | -i <string>
    Input volume.

--output | -o <string>
    Output bucket.

[ --channel | -c <string> ]
    Channel to use if color image: r[ed], g[reen], b[lue], n[orm] (default)

--npoints | -n <S64>
    Number of points to extract.

[ --balance | -b <FLOAT> ]
    Equilibriate probabilities. Number in [0,1].
    - If 0, the density is kept as is.
    - If 1, all points are equiprobables
    (default: 0)

[ --zero | -z <boolean> ]
    Include points with null gradient when balancing. (default: false)

[ --output_4d_volumes <S32> ]
    Write 4D images as several 3D files (0 = series of 3D volumes, 1 = one 4D
    volume, no value = use .aimsrc configuration files)

[ --debugLevel | -d <S32> ]
    Set debug information level (default = 0)

[ --verbose | -v [ <S32> ] ]
    Set verbosity level (default = 0, without value = 1)

[ -h | --help <boolean> ]
    show help message

[ --version <boolean> ]
    show Cartograph version

[ --info <boolean> ]
    show libraries information (install, plugins, paths, etc.)

[ --optionsfile <string> ]
    Read additional commandline options from the specified file (one switch or
    value per line)