DragonFly On-Line Manual Pages
JPEG2PS(1) JPEG2PS(1)
NAME
jpeg2ps - convert JPEG compressed images to PostScript Level 2 or 3
SYNOPSIS
jpeg2ps [-a] [-b] [-h] [-o name ] [-p size ] [-q] [-r dpi ] file.jpg >
file.eps
DESCRIPTION
jpeg2ps reads a JPEG file (not stdin) and writes a DSC-compliant EPS
file containing the compressed JPEG data in PostScript format to
stdout. The produced EPS files contain the necessary DSC comments
including BoundingBox, so they may be imported in page layout
applications. However, they do not contain preview images, so you will
only see a gray box on screen.
The jpeg2ps program performs some sanity checks with the JPEG data. It
detects several kinds of corrupt input data, but it is not absolutely
foolproof. One special feature is that you can feed Macintosh JPEG
files (PICT-JPEG) to jpeg2ps. These normally have several hundred
bytes of additional stuff before the JPEG data. This PICT rubbish is
simply ignored by jpeg2ps.
OPTIONS
-a
Auto rotate feature. If the auto rotate feature is activated,
images with width > height are automatically rotated to
landscape mode. The image is scaled in a way to use at least one
full edge of the paper. A 20 pt margin is subtracted on each
side. Page sizes can be chosen with the -p option. The default
page size is letter or a4, depending on the compilation flags.
Don't use this option if you simply want to generate EPS files
for inclusion in your documents.
-b Binary mode. By default, jpeg2ps sends the image data in ASCII85
encoded form which is suitable for any communication channel
(serial, parallel or whatever). If you are sure that your
channel is truly 8-bit clean, you can force 8-bit data with this
option. Note that this normally does not apply to 8-bit serial
or even parallel channels since some control characters are
reserved for the communications protocol. You can use binary
data e.g.: with some networked printers, with direct-access
PostScript interpreters, e.g. Ghostscript, or serial and
parallel channels using Binary Control Protocol (BCP).
-h Hex mode (ASCIIHex encoding). Using this option, jpeg2ps
generates 7-bit clean data by using ASCIIHex encoding instead of
the more space-efficient ASCII85 encoding. This is only useful
for specialized applications, e.g. for debugging, since jpeg2ps
requires PostScript Level 2 anyway, and ASCII85 is supported in
any Level 2 interpreter.
-o name
Output file name (as an alternative to output redirection).
-p size
Page size name. Known names are: a0, a1, a2, a3, a4, a5, a6, b5,
letter, legal, ledger, p11x17
-q Quiet mode: suppress all informational messages
-r dpi
Resolution value. Using this option you can force jpeg2ps to use
a certain dpi value. Since automatic actions are also disabled
in this case, you are responsible for choosing a reasonable
resolution value. For example, you can print a 300 dpi image
half-sized by supplying -r 600. The option "-r 0" instructs
jpeg2ps to look for a JFIF density/resolution marker and use
that value. Automatic scaling and rotation are disabled.
However, if no resolution information is found in the file,
jpeg2ps applies the default algorithm described above.
DIAGNOSTICS
The jpeg2ps program issues three kinds of messages:
Notes Have an informational character.
Warnings
A potential problem with the file was recognized, processing
continues.
Errors Either a severe problem within the JPEG file was found or the
file explores JPEG features not compatible with PostScript Level
2.
Note that there are some JPEG producers which do not exactly conform to
the specification and that the JPEG spec itself does not cover every
aspect of the file format. You are on the safe side if you demand JFIF
files which are happily accepted by jpeg2ps. (For further information
see the JPEG FAQ by Tom Lane.)
SHAMELESS PLUG
My book contains a lot of information on PostScript, Fonts, and PDF
(currently only available in German):
Die PostScript- & PDF-Bibel
Von Thomas Merz und Olaf Druemmer
654 Seiten, ISBN 3-935320-01-9
Kopublikation PDFlib GmbH/dpunkt Verlag
http://www.pdflib.com/bibel
e-mail orders: books@pdflib.com
AUTHOR
Thomas Merz <tm@pdflib.com>
http://www.pdflib.com
LICENSE
This software is free. You are granted the right to use and copy it.
This software may not be sold or bundled with any commercial package
without express written permission of the author.
The author accepts no responsibility for damages resulting from the use
of this software and makes no warranty, either express or implied,
including but not limited to, any implied warranty of merchantability
or fitness for a particular purpose. This software is provided as is,
and you assume all risks when using it.
February 2, 2002 JPEG2PS(1)