Ppmtospu User Manual(1) General Commands Manual Ppmtospu User Manual(1)
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 Stan-
dard 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 ]8;;index.html#commonoptions\ Common Options]8;;\ ), 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 re-
tained 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)
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