Northern Eclipse Help Reference

 Colormap Editor

The Colormap Editor is used to make custom color Lookup Tables (LUT’s).  A color LUT can be used to apply false colors to a monochrome image or to remap the colors of a 24-bit image (for color correction).  Also, some 24-bit color images can be approximated by using a colormap of well chosen colors, and therefore take up only the space of an 8-bit monochrome image.   See Apply Colormap for more information.

The Line button allows you to make gradient ramps between two values. 
The Point button allows freehand drawing of the colormap. 
The Smooth button smoothes out the curve. 
The Apply button applies this curve to the current image.
The Load and Save buttons bring up load and save dialogs respectively.

You can view a single color plane or all planes using the drop down box.  This is useful if you only want to adjust a particular plane, or want to see if the LUT curves are aligned.

Since the human eye is only capable of distinguishing between 20 to 30 gray values under good conditions, but can easily distinguish hundreds of thousands of colors, Pseudo-color (or false color) can be a powerful way to display small gray level variations. The Color Map Editor allows any one of 16.7 million color combinations to be assigned to a given gray value. Adding a LUT to an image does not really change any of the gray values of the original image that might affect subsequent measurements. To change an image back to monochrome after a color map has been applied, re-apply a Normal color map (all three lines would be drawn linear to make a Normal color map), or using the Copy Plane function pull off the Index plane of a Pseudo-colored image.


Note that you can convert an image that has a palette into a 24-bit image by using the Convert to 24-bit function.


See Also

Apply Colormap


Table of Contents
Function Reference
Menu Reference
Toolbar Reference