Color Raster Images
The suggested method for printing color images is by using 24-bit,
direct color pixels with delta row compression. The 24-bit, direct color
is specified using the Configure Image Data command. Delta row
compression is recommended over run length, or TIFF pack bits
since 24-bit, direct color uses three bytes per pixel so there is little
redundancy from one byte to the next. Delta row compression exploits
the redundancy from row to row, and therefore yields better
compression than any other supported PCL compression mode.