Name

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      THICKEN

Purpose

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      Thicken graphics in an existing image. Good for viewgraphs.

Category

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Calling Sequence

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      thicken, img, color

Inputs

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      color = color index to thicken. in

Keyword Parameters

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Keywords

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        BOLD=b Desired thickness (def=2).
          BOLD may also be set to an N x M array which defines
          a brush stroke by non-zero elements. For example:
          BOLD=shift(dist(3),-2,-2) lt 1.2
        SUBSTITUTE=nclr New color to replace color by after
          thickening. Needed for multiple calls. For example,
          to thicken multiple black lines, need a temporary color
          to thicken and then substitute black:
          thicken,img,clr,sub=0 will thicken clr, then make it
          be 0.
        /NOCENTER thicken on positive side of points (default is
            to center thickening.
        MASK=m Optionally returned mask with 1 for pixels
          in thickened areas, else 0. May be useful for more
          complex processing.
        /QUIET means suppress non-serious messages.

Outputs

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      img = input image (byte). in, out

Common Blocks

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Notes

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      Notes: Useful to make existing graphics such as axes,
        text, data curves, and so on thicker in an existing
        image. Makes viewgraphs more readable. May want to
        make original graphics in different colors so thickness
        can be customized: For axes use 0, for text use 1, ...

Modification History

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      R. Sterner, 1994 Feb 2.
      R. Sterner, 1994 Apr 4 --- Allowed 2-d brush stroke.
  Copyright (C) 1994, Johns Hopkins University/Applied Physics Laboratory
  This software may be used, copied, or redistributed as long as it is not
  sold and this copyright notice is reproduced on each copy made. This
  routine is provided as is without any express or implied warranties
  whatsoever. Other limitations apply as described in the file disclaimer.txt.