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

EN Using Color Modes 2-9
PEM 1: INDEXED BY PIXEL
In this mode, each pixel in a row is fully specified before any bits are
sent for the next pixel. The bits for each pixel form a palette index
number. Assuming four bits per index, the underlined block below is
the palette index for pixel two of row one (i1 is the least significant bit).
?*b#W row 1 i4 i3 i2 i1 i4 i3 i2 i1 . . .
?*b#W row 2 i4 i3 i2 i1 i4 i3 i2 i1 . . .
?*b#W row 3 i4 i3 i2 i1 i4 i3 i2 i1 . . .
Example:
In the example below the data in the row transfer commands are
shown as two-digit hexadecimal numbers for clarity, even though the
actual data would be byte-aligned binary data. The example is for a
two-pixel-wide image.
?*v6W 00 01 04 08 08 08 Binary Data for the CID
command represented in
hexadecimal. This command
sets the color space to RGB, the
PEM to Indexed by Pixel, the
palette size to 16 (2
4
). The last
three bytes are ignored.
?*r1A Start raster
?*b1W45 The most significant nibble
selects palette entry 4 for the
first pixel. The second pixel is set
to index 5. Move to next row.
?*b1W6A The first pixel is index 6, the
second pixel is index 10. Move to
the next row.
?*b1W03 The first pixel is index 0, the
second pixel is index 3.