1 SMOOTH
        SMOOTH

    Smooths an input map  using  various   methods,   all   based   upon   a
    convolving  kernel  of  5  points large only.  This method is crude, but
    very fast,  and  supports  blanking  in  principle...   Data  cubes  are
    processed plane by plane.

      1.  BOX A simple 5 by 5 boxcar smoothing.  This is   a   very   strong
        smoothing...
      2.  GAUSS A gaussian smoothing.  The gaussian is sampled on a 5  by  5
        grid   so  it  must not be too broad.  3 pixels seem a maximum.  Use
        task  GAUSS_SMOOTH  if  you  want   to   smooth   with   a   broader
        gaussian,   but   beware   it   does   not  handle  properly blanked
        pixels.
      3.  HANNING Smoothing by a 5 by 5 pyramid, with weights 3 2 1.
      4.  USER User defined smoothing coefficients on  a  5   by   5   grid,
        assuming   biaxial   symmetry.    Hence   6   coefficients  only are
        required, S00 S10 S11 S20  S21  S22.   The  corresponding  smoothing
        kernel is :
                                S22 S21 S20 S21 S22
                                S21 S11 S10 S11 S21
                                S20 S10 S00 S10 S20
                                S21 S11 S10 S11 S21
                                S22 S21 S20 S21 S22
        Such a generalised  "smoothing"  enables  some   image   enhancement
        based   on   gradients   (e.g.    with   weights 4 -1 0 0 0 0).  The
        "smoothed" image is normalised by the sum of absolute values of  the
        coefficients.

2 Y_NAME$
        TASK\FILE "Input image" Y_NAME$

    The name of the input image.
2 X_NAME$
        TASK\FILE "Smoothed output image" X_NAME$

    The name of the output smoothed image.
2 BLANKING$
        TASK\REAL "Blanking value and tolerance" BLANKING$[2]

    The blanking value and its tolerance in the input map.  This information
    is only used if it is not present in the header of the input map.
2 METHOD$
        TASK\CHARACTER "Smoothing Method" METHOD$

    The name of the smoothing method.  Supported methods are  BOX,  HANNING,
    and GAUSS.
2 WIDTH$
        TASK\REAL "Gaussian width in pixels" WIDTH$

    The width (in pixels)  of  the  smoothing  gaussian.   Beware  that  the
    gaussian  is  only  sampled on a 5x5 grid:  do not specify values higher
    than 3.
2 WEIGHT$
        TASK\REAL "Coefficients" WEIGHT$[6]

    The 6 smoothing coefficients for USER method. These coefficients are  in
    order 00 01 11 02 12 22. See EXPLAIN SMOOTH for details.
1 END