PSTOJPEG 1 "07 April 2001" "Version 1.00"

Table of contents


NAME

pstojpeg - convert (Encapsulated) PostScript files to JPEG bitmap files

SYNOPSIS

pstojpeg [ -? ] [ -crop ] [ -debug ] [ -extension name ] [ -gamma float-value ] [ -help ] [ -icon ] [ -margin pixels ] [ -norun ] [ -quality percent-value ] [ -resolution dpi ] [ -version ] [ -Wcomponent,option ] PostScript-files

DESCRIPTION

pstojpeg converts one or more input (Encapsulated) PostScript files to output Joint Photographic Experts Group (JPEG) lossy compressed bitmap files.

For maximal color fidelity, bitmaps are produced in 24-bit color mode, with 16,777,216 possible colors.

For each file given on the command line, an output file is written with the same basename as the input file, but with extension jpeg, or the name specified by the -extension option.

With the -icon option, small companion files with the same name are also written in a subdirectory icons, which is created if necessary.

If no files are given on the command line, then stdin is read, and stdout is written, and no icon file can be produced.

pstojpeg is a convenient interface to cjpeg(1), gs(1), pnmcrop(1), pnmmargin(1), and pngtopnm(1), which do the real work.


OPTIONS

Command-line options may be abbreviated to a unique leading prefix.

To avoid confusion with options, if a filename begins with a hyphen, it must be disguised by a leading absolute or relative directory path, e.g. /tmp/-foo.eps or ./-foo.eps.

Options may begin with either UNIX-style single hyphens, or GNU/POSIX-style double hyphens, and may be abbreviated to any unique prefix.

-crop
Crop the image to remove edges that are the background color.
-debug
Turn on debug tracing.
-extension name
Replace the default output file extension, xps, with name.
-gamma float-value
Specify an image gamma correction as a floating-point number. Small values darken the image, and large values lighten it. Typical values are in the range 0.5 .. 3.0.

[Default: 1.0]

-?

-help
Display a brief help message on stdout, and exit with a success status code (0 on UNIX).
-icon
Produce icon files as well as JPEG files. An icon file is just a low-resolution (12dpi) bitmap that may be useful as a compact representation of what is in the JPEG file.

In filter mode (no files on the command line), this option is ignored.

-margin pixels
Add a background margin of width pixels to the output image. This option is usually specified together with -crop.
-norun
Show on stdout the commands that would be executed, but do not run them.

Use this option to trap the complex command pipelines for further private customization.

-quality percent-value
Specify the JPEG quality parameter as a value in 0..100.

Unlike the lossless PNG and TIFF bitmap formats, the JPEG format is lossy, sacrificing quality to reduce data size. A quality value of 100 avoids quality loss, and smaller values produce smaller files of lower quality.

Warning: The JPEG format is suitable for continuous tone images, such as digital photographs, but introduces ghost artifacts in regions of a single color, such as a solid background in a line drawing. The artifacts are most evident at small quality values, and disappear as the quality value is increased to 100.

[Default: 25]

-resolution dpi
Set the output bitmap resolution to dpi dots per inch.

[Default: 100 dpi, suitable only for screen resolution].

-version
Display program version numbers and dates on stdout, and exit with a success status code (0 on UNIX).
-Wcomponent,option
Pass option to the program component, which must be one of cjpeg, gs, pngtopnm, pnmcrop, or pnmmargin.

This option, a POSIX convention, provides a general way for a user to pass options to programs invoked by another program. The value option is passed after any generated in response to options supplied to pstojpeg. For example, -Wpnmmargin,-black would cause any added margin to be colored black.


SEE ALSO

cjpeg(1), epsutil(1), gimp(1). gs(1), photoshop(1). pngtopnm(1), pnmcrop(1), pnmmargin(1), pstopng(1), pstotiff(1), xv(1).

AUTHOR

Nelson H. F. Beebe, Ph.D.
Center for Scientific Computing
University of Utah
Department of Mathematics, 322 INSCC
155 S 1400 E RM 233
Salt Lake City, UT 84112-0090
Tel: +1 801 581 5254
FAX: +1 801 585 1640, +1 801 581 4148
Email: beebe@math.utah.edu, beebe@acm.org,
       beebe@computer.org, beebe@ieee.org
WWW URL: http://www.math.utah.edu/~beebe