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

EN Color Printing Overview (Color LaserJet, 5, 5M, DeskJet) A-7
Encoding by Pixel
When encoding by pixel, each pixel is fully specified before any bits
are sent for the next pixel. For example, if four bits are needed to
define a pixel, then every group of four bits in the data stream defines
a pixel. The underlined (c4 . . . c1) group below defines the second
pixel in the first row.
The table below shows the four PCL options for selecting colors and
encoding color raster data.
Color Modes
There are four PCL 5 color modes:
• Black and White mode
• Simple Color mode
• PCL Imaging mode
• HP-GL/2 Imaging mode
All four modes create a palette. The palettes used in the Black and
White mode and Simple Color mode are not modifiable. You can,
however, modify the palettes in the PCL Imaging and HP-GL/2
Imaging modes.
You can use more than one mode on the same page. For example,
you could enter the Simple Color mode to print a headline and a bar
chart, PCL Imaging mode to print a raster photograph, and Black and
White mode to print some body text. Each mode is described in more
detail in Appendix B, “Using Color Modes.”
?*b#W row 1 b4 b3 b2 b1 c4 c3 c2 c1 . . .
?*b#W row 2 b4 b3 b2 b1 . . .
Planar Encoding Pixel Encoding
Indexed
Selection
Indexed planar Indexed pixel
Direct
Selection
Direct planar Direct pixel