NAME

       ppmtospu - convert a PPM image to an Atari Spectrum 512 image

SYNOPSIS

       ppmtospu

       [-d0|-d2|-d4] [ppmfile]

       All  options can be abbreviated to their shortest unique prefix.  You may use two hyphens instead of one.
       You may separate an option name and its value with white space instead of an equals sign.

DESCRIPTION

       This program is part of Netpbm(1).

       This program converts from the PPM format to the uncompressed Spectrum 512 image format used on Atari  ST
       computers.

       Input  comes from the file you name with the ppmfile argument, or Standard Input by default.  Output goes
       to Standard Output.

       The input must be 320 pixels wide by 200 pixels high.  If you have an image of a different size, you  can
       use pamcut or pamscale to force it to these dimensions.

OPTIONS

       In  addition  to  the options common to all programs based on libnetpbm (most notably -quiet, see  Common
       Options ), ppmtospu recognizes the following command line options:

       -d0    The program does no dithering.

       -d2    The program uses a 2x2 ordered dither.

              This is the default.

       -d4    The program uses a 4x4 ordered dither.

SEE ALSO

       sputoppm(1), spctoppm(1), pamscale(1), pamcut(1), ppm(1)

AUTHOR

       Copyright (C) 1990 by Steve Belczyk

HISTORY

       This program was new in Netpbm 10.58 (March 2012).

       But it was written in 1990.  Steve Belczyk  posted  it  along  with  sputoppm,  spctoppm,  pi1toppm,  and
       pi1toppm  -  all  programs  for dealing with Atari image formats - to comp.sources.misc on July 15, 1990.
       For reasons that have been lost to history, all of these entered the Netpbm (then  Pbmplus)  distribution
       except ppmtospu.

       Georges  Kesseler  wondered In March 2012 why there was no counterpart to sputoppm in Netpbm and searched
       the web, finding only one reference to ppmtopsu: the 1990 comp.sources.misc posting, including the source
       code.  He emailed the Netpbm maintainer suggesting it be added.

       Bryan Henderson found the source code to be extremely primitive, not even using common library code.   So
       Bryan completely recoded it, but retained nearly all of the original logic.

DOCUMENT SOURCE

       This  manual  page was generated by the Netpbm tool 'makeman' from HTML source.  The master documentation
       is at

              http://netpbm.sourceforge.net/doc/ppmtospu.html

netpbm documentation                              08 March 2012                          Ppmtospu User Manual(1)