NAME
rletops - Convert RLE images to PostScript
SYNOPSIS
rletops [ -C ] [ -a aspect ] [ -b bits ] [ -c center ] [ -h height ] [
-m minrun ] [ -o outfile.ps ] [ -r ] [ -s ] [ infile ]
DESCRIPTION
Rletops converts RLE(5) images into
PostScript. The conversion uses the
PostScript image operator, instructing the
device to reproduce the image to the best of
its abilities. If infile isn't specified,
the RLE image is read from stdin. The
PostScript output is dumped to stdout, or to
outfile.ps, if specified.
OPTIONS
-a aspect
Specify aspect ratio of image. Default
is 1.0 (note PostScript uses square
pixels).
-b bits
Reduce the image to bits bits per
channel by dithering. This can
significantly reduce the size of the
resulting postscript file and therefore
the time required for printing. It may
reduce the image quality as well. bits
must be 1,2,4 or 8. The default is 8.
-C Causes a color PostScript image to be
generated. This creates larger files
and uses the PostScript colorimage
operator, which is not recognized by all
devices. The default is monochrome.
-c center
Centers the images about a point center
inches from the left edge of the page
(or left margin if -s is specified).
Default is 4.25 inches.
-h height
Specifies the height (in inches) the
image is to appear on the page. The
default is three inches. The width of
the image is calculated from the image
height, aspect ratio, and pixel
dimensions.
-m minrun
Specifies the minimum length run for run
length encoding of the output. The best
value in terms of the postscript file
size is 4, but this does not necessarily
produce the fastest postscript. The
default value (25) has been selected
empirically to minimize printing time
for the apple laserwriter operating on a
19.2K baud serial line. Your mileage
may vary.
-r Reverse the sense of white and black.
0: white; 1: black.
-s Specifies image is to be generated in
"Scribe Mode." The image is generated
without a PostScript showpage operator
at the end, and the default image center
is changed to 3.25 inches from the
margin (which usually is 1 inch). This
is to generate PostScript files that can
be included in Scribe documents with the
@Picture command. Images may also be
included in LaTex documents with local
conventions like the
\special{psfile=image.ps} command.
NOTES
On devices like the Apple LaserWriter,
rletops generates large PostScript files that
take a non-trivial amount of time to download
and print. An uncompressed 512x512 image
takes about ten minutes. Images with long
runs of constant value may be faster. For
including images in documents at the default
sizes, 256x256 is usually sufficient
resolution.
SEE ALSO
avg4(1), urt(1), RLE(5).
AUTHORS
Rod Bogart, John W. Peterson, Gregg Townsend,
James Painter.
Portions are based on a program by Marc
Majka.
BUGS
The dithering implied by the -b option may
The run length encoding in the postscript
file is ineffective for color images.
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