DITHERING

[mberger at RELAY.NSWC.NAVY.MIL]

     Does any one have any dithering functions/programs?

     I am trying to convert a 256 color grayscale image into a 16
color grayscale image.  I have tried a straight conversion, as well
as the ordered dither, and error diffusion algorithms described in
'Fundamentals of Interactive Computer Graphics'.  All of these methods
give very contoured images.

                                             Thanks in advance
                                             Mike