, fg, ...)
overlayPlot(x, y, bg, fg)
overlayPlot(x, y, bg, fg, ...)
</pre>

<h2>Description</h2>
<p><code>overlayPlot</code> overlays two 2D images. The background image is displayed using a grayscale map. For a non-zero dynamic range, the foreground image is log compressed (discarding negative values), thresholded to a particular dynamic range, and overlaid using an alpha value of 0.5. If the dynamic range is set to zero, the foreground image is overlaid without additional processing.</p>

<p>Example:</p>
