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Overlay Tool

This displays more than three images as a color overlay.


  • To use:
    • Click on an image.
    • Click 'Add Image' & select color
    • Repeat

Note - Image names are right justified at the green arrow, and colors are left justified.  This is supposed to make the list easier to read when some image titles (names) are long.



This tool is analogous to the 2 & 3 Variable Tool, but it will work, with varying success, on more than three images.  In the 2 & 3 Variable Tool, you assign each of three images to one of three colors (color components of a color overlay), red, green and blue.  In this Overlay Tool, you assign a color to each image, then the red, green and blue components are combined and displayed (as an RGB overlay).  In this Tool, the images, are not displayed strictly indepently as in the RGB overlay where one image only is shown by one color component.  Here, more than one image may be represented in one or more of the color components. However the results may still be useful.  For example:

Here is an example set of four images.

To assign colors, click on an image, then click on Choose colors.  There are a variety of methods of choosing the color for each image, including

  • the primary colors
  • combinations of the primary colors such as yellow
  • the current color of the color menu
  • selection from the choose color dialog
  • typing in the R, G and B components, either as a fraction (yellow would be 1.0 1.0 0) or as an intensity (yellow would be 255 255 0)

The Delete image button removes one or more image & color combination from the list shown in the tool.

There are several overlay methods and scaling methods.  Here is the result for the defaults:

(old version of the tool)


The Make Overlay Button makes the color overlay.