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Basic Information on vblank

Task: vblank
Purpose: mask outlier pixels on the spectral axis
Categories: image-analysis

        VBLANK takes a cube that has already been masked and masks it
        further so that unmasked pixels that are surrounded by only
        masked pixels along axis 1 will be masked.  The default is to
        mask if both adjacent pixels are masked; one can increase the
        window size with keyword 'tol'.
        This can be useful for reducing noise in a datacube that has
        already been masked with a smoothed cube and where the velocity
        field is assumed to be smooth.  In this case axis 1 would be the
        velocity axis and spikes far from the channels of actual
        emission are masked.
        NOTE: Because flagging is only implemented for planes, the
        spectral axis must be axis 1.  Use REORDER first to make this
          reorder in=file1 out=file2 mode='312'
          vblank  in=file2
          reorder in=file2 out=file3 mode='231'

Key: in
          Standard keyword in. See the help on in for more information.

Key: tol
        How far (in pixels) the nearest unmasked pixel can be for the
        given pixel to stay unmasked.  Default is 1.
Revision: 1.3, 2011/04/04 05:56:01 UTC

Generated by miriad@atnf.csiro.au on 21 Jun 2016