.sp
.LP
These routines convert images to a black pixel/white pixel image for
use on monochrome screens or printers without pre-dithering algorithms.
.SH
SHORT DESCRIPTION OF ROUTINES
.IP "Dither Image -" 20
 Perform dithering using ordered (matrix) technique.
.IP "Optimize 45 deg. -" 20
Perform dithering using ordered (matrix) technique, 
optimized for 45 degrees.
.IP "By Error Diffusion -" 20
Perform dithering by four-direction error diffusion.
