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Basic Information on smooth


Task: smooth
Purpose: Convolve an image (in the image domain) with a 2-D Gaussian
Categories: analysis

        SMOOTH is a MIRIAD task that convolves an image by an elliptical
        Gaussian or a boxcar the hard way.  The convolving Gaussian and
        boxcar have peaks of unity.  Additional scaling is provided by
        the keyword "scale"
 
        By default, SMOOTH will mask pixels in the output image if
        there are more masked pixels than unmaked pixels in the
        Gaussian convolution area. This means that pixels which were
        maked in the input may be unmasked in the output.

Key: in
        The input image.  Wild card expansion is supported, no default.

Key: out
        The output image.  No default.

Key: type
        Specifies the type of function to convolve by.  Should
        be one of
          "gaussian"     Gaussian at arbitrary position angle
          "boxcar"       Boxcar oriented in x and y directions. Note
                         that the full width is rounded up to be an
                         odd number of pixels.
        Default is gaussian.  Minimum match is active.

Key: fwhm
        The Gaussian FWHM along the major and minor axes or the boxcar
        full widths in the x and y directions (all in arcseconds).
        The image pixel increments are assumed to be in radians.
        No default.

Key: pa
        The position angle in degrees CCW from North of the major axis
        of the Gaussian.  Not used for boxcar smoothing.
        Default is 0.0.

Key: scale
        If unset, then SMOOTH will attempt to make the units of the
        smoothed image be Jy/beam for Gaussian convolution.  If 0.0,
        then the convolution integral is scaled (multipled) by the
        inverse of the volume of the convolving function. Otherwise,
        the integral is scaled by "scale"

Key: options
        "nocheck"   By default, blanked input pixels do not contribute
           to the convolution sum.  If you set NOCHECK then blanked
           input pixels are not checked for (but the output image is
           blanked around the unconvolved edge, and wherever the input
           image is blanked).
        "force"     Force masking of pixels in the output image which
           are masked in the input image.
 
Revision: 1.6, 2021/06/02 04:45:09 UTC

Generated by miriad@atnf.csiro.au on 02 Jun 2021