HP PCL/PJL reference (PCL 5 Color) - Technical Reference Manual

EN Color Printing Overview (Color LaserJet, 5, 5M, DeskJet) A-3
Color Concepts
This section describes some of the concepts and terminology used in
this chapter, such as palettes, raster vs. non-raster color,
device-independent vs. device-dependent color, black and white
references, color selection, pixel encoding, and color modes.
Palettes
A palette is a collection of colors that are selected by their index
numbers. You can create your own palette or choose from one of
several fixed palettes. Although only one palette is active at any time,
all palettes are assigned ID numbers and can be stored in the printer
for later selection using the ID number. They can be deleted when
desired. Palettes can also be saved (pushed) to a stack and later
retrieved (popped) when needed.
Raster Mode
Raster mode is entered explicitly by the Start Raster command
(
?*r#A) or implicitly by a Transfer Raster command (?*b#V,
?*b#W). Raster mode is exited explicitly by an End Raster command
(
?*rC) or implicitly by a non-raster command.
Raster Color vs. Non-Raster Color
Palettes are used differently depending on whether the printer is in
raster mode.
• In non-raster mode, the palette is always used for color
selection. The color of text or patterns is specified using the
Foreground Color command (
?*v#S).
• In raster mode, the palette is only used for indexed color
selection; it is not used for direct color selection. (Indexed and
direct color selection are explained later in this section.)