!COLOR: Contains standard RGB color triplets.
            CMYK_CONVERT: Converts color triples to and from RGB, HLS, and HSV.
            COLOR_QUAN: Converts true-color (24-bit) image to pseudo-color (8-bit) image.
            COLORMAP_APPLICABLE: Determines whether the current visual class supports the use of a colormap. (Direct Graphics)
            CT_LUMINANCE: Calculates the luminance of colors.
            CW_COLORGRADIENT: Creates a compound widget to create color palettes built as gradients interpolated between a series of user-defined colors.
            CW_PALETTE_EDITOR : Creates a compound widget to display and edit color palettes.
            CW_PALETTE_EDITOR_GET: Gets CW_PALETTE_EDITOR properties.
            CW_PALETTE_EDITOR_SET : Sets CW_PALETTE_EDITOR properties.
            DIALOG_COLORGRADIENT: Allows you to interactively define a color table as a gradient interpolated between a series of user-defined colors.
            GAMMA_CT: Applies gamma correction to a color table.
            H_EQ_CT: Histogram-equalizes the color tables for an image or a region of the display.
            H_EQ_INT: Interactively histogram-equalizes the color tables of an image or a region of the display.
            HLS: Creates a color table in Hue, Lightness, Saturation color system.
            HSV: Creates a color table based on Hue and Saturation Value color system.
            IDLgrPalette: An object that contains a red-green-blue color lookup table.
            LOADCT Procedure: Loads one of the predefined IDL color tables. (Direct Graphics)
            MODIFYCT Procedure: Saves modified color tables in the IDL color table file. (Direct Graphics)
            MULTI Procedure: Replicates current color table to enhance contrast. (Direct Graphics)
            PSEUDO: Creates a pseudo-color table based on Lightness, Hue, and Brightness system.
            REDUCE_COLORS: Reduces the number of colors used in an image by eliminating unused pixel values.
            STRETCH: Stretches a color table for contrast enhancement.
            TEK_COLOR Procedure: Loads color table based on Tektronix printer. (Direct Graphics)
            TVLCT Procedure: Loads a color table. (Direct Graphics)
            XLOADCT Procedure: Provides GUI to interactively select and load color tables. (Direct Graphics)
            XPALETTE Procedure: Displays widget used to create and modify color tables. (Direct Graphics)