The PSEUDO procedure creates a pseudo- color table based on the LHB (Lightness, Hue, and Brightness) system and loads it.
The pseudo-color mapping used is generated by first translating from the LHB coordinate system to the LAB coordinate system, finding N colors spread out along a helix that spans this LAB space (supposedly a near maximal entropy mapping for the eye, given a particular N ) and remapping back into the RGB (Red, Green, and Blue) colorspace. The result is loaded as the current colortable.
This routine is written in the IDL language. Its source code can be found in the file
subdirectory of the IDL distribution.