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\input texinfo @c -*-texinfo -*-
@c %**start of header
@setfilename epspdf.info
@settitle Epspdf and epspdftk User Guide 0.5
@afourpaper
@c %**end of header

@ifhtml
@alias chapter = unnumbered
@alias section = unnumberedsec
@alias subsection = unnumberedsubsec
@end ifhtml

@tex
\input pstexi
@end tex

@iftex
@textfonts
@rm
@raggedbottom
@hyphenation{epspdf-tk epspdf}
@end iftex

@set version 0.5.2
@set homepage http://tex.aanhet.net/epspdf/

@setchapternewpage off
@paragraphindent none

@copying
This manual is for epspdf, version @value{version}.

Copyright @copyright{} 2006, 2008, 2009, 2010 Siep Kroonenberg.

@quotation
Copying and distribution of this file, with or without modification,
are permitted in any medium without royalty provided the copyright
notice and this notice are preserved.  This file is offered as-is,
without any warranty.
@end quotation
@end copying

@titlepage
@sp 1
@center @image{images/logo,,.4in}
@sp 2
@center @titlefont {Epspdf and epspdftk User Manual}
@sp 1
@center A multiplatform GUI- and command-line converter for [e]ps and pdf
@sp 2
@center Siep Kroonenberg (@email{n dot s dot kroonenberg at rug dot nl})
@vskip 0pt plus 1filll
@insertcopying
@end titlepage

@contents

@ifnottex
@node Top, Usage, (dir), (dir)
@top Epspdf and epsdftk

@insertcopying
@end ifnottex

@menu
* Usage::
* Command-line usage::
* Notes on PostScript and pdf::
* Bitmapped graphics for @LaTeX{} and pdflatex::
* Troubleshooting::
* Change history::

@detailmenu
 --- The Detailed Node Listing ---

Usage

* Overview::
* Viewing::
* Conversion options::
* Converting::
* The configuration screen::

Command-line usage

* Option summary::

Notes on PostScript and pdf

* Bitmapped and vector::
* Font embedding::
* Eps preview headers::
* Bounding- and other boxes::
* Orientation::
* Exporting PostScript from Windows programs::

Bitmapped graphics for @LaTeX{} and pdflatex

* Linux::
* Mac OS X::
* Windows::

Windows

* GUI use of sam2p and bmeps::

Troubleshooting

* Grayscaling fails::
* Part of the graphic gets cut off::
* Fonts look ugly::
* epspdftk quit unexpectedly (Mac OS X applet)::
* Resources for troubleshooting::

Change history

* Version 0.5::
* Version 0.4::

@end detailmenu
@end menu

@node Usage, Command-line usage, Top, Top
@chapter Usage

@menu
* Overview::
* Viewing::
* Conversion options::
* Converting::
* The configuration screen::
@end menu

@node Overview, Viewing, Usage, Usage
@section Overview

Epspdftk converts files between eps, pdf and general
PostScript. The main screen lets you open a file, select some options
and convert the file.

When opening a file, epspdf tries to find out file type and, in
the case of a pdf file, the number of pages. This information is
displayed in the box in the upper part of the screen.

@noindent @image{images/main_w32,,3in}
@iftex
@hfill
@end iftex
@image{images/cnv_osx,,3in}

@node Viewing, Conversion options, Overview, Usage
@section Viewing

The View button at the bottom of the screen calls an appropriate
external viewer.

@i{Windows and OS X:} Epspdftk simply tries to use the default Open
command.

Under Linux the PostScript- and pdf viewers are
configurable; see @ref{The configuration screen}.

The View button is grayed if epspdf thinks that there is no
previewer for the current file.

@node Conversion options, Converting, Viewing, Usage
@section Conversion options

@anchor{gray}@i{Grayscaling:} Simple color figures can be converted to
grayscale. Bitmapped data won't be converted. If grayscaling doesn't
work even on non-bitmapped data, select the ``Try harder to
grayscale'' option. This may cause an extra pdf-PostScript roundtrip,
but grayscaling may still fail.

@i{Compute tight boundingbox:} This option is only available
if a single page is converted.

@i{Page selection:} The only possibilities are selecting a
single page or selecting all pages. When converting to eps you are
restricted to a single page.

For general PostScript files, there is no quick way to determine the
number of pages, so the program may not check beforehand whether you
picked an existing page. If you don't like that, convert the entire
document to pdf first -- which will be done behind the scenes anyhow.

Specifying options such as grayscaling or page selection may require
several roundtrips between PostScript or eps and pdf.

@node Converting, The configuration screen, Conversion options, Usage
@section Converting

The Convert and save... button calls up a file save dialog. After a
successful conversion, the result becomes the new current file, so you
can judge the result by pressing the View button again.

@node The configuration screen,  , Converting, Usage
@section The configuration screen

@image{images/config_lnx,3in}

Epspdftk also has a configuration screen. The settings here are
preserved between sessions.

@subsection Configuring viewers

Under Unix, the preferred PostScript- and pdf viewers can be configured
in this screen. Epspdf looks for a number of PostScript- and pdf
viewers, from which you can select one, but you can also enter one
manually.

For Windows and Mac OS X, there is no such configuration option. Epspdf
will use the program associated with the file type, which can be
configured outside epspdf.

@subsection Options for converting to pdf
Double-check the setting ``Target use'' under ``Conversion to
pdf''. Choose ``prepress'' for pdfs which are target for commercial
printing. This option will try to embed all fonts, among other
things. Often, printshops insist on this. With luck, Ghostscript fonts
and system fonts will be used for fonts which were not originally
embedded.

On the other hand, you may prefer ``screen'' if file size is a
concern. See also the Ghostscript documentation, in particular Use.htm
and Ps2pdf.htm.

@subsection Options for converting to PostScript
For conversion the other way you may opt @i{not} to use pdftops even if
it is available. In this case, the conversion will be done by
Ghostscript. Characters may be converted to drawn shapes or little
bitmaps so this is not recommended if the file uses fonts.

Under Windows, this is also the place to point the program to the
location of pdftops.exe.

@anchor{hires}@subsection Hires BoundingBox
Uncheck the option ``Use hires boundingbox if possible'' if your
conversions come out slightly clipped. It has two effects:
@itemize @bullet
@item
When converting to pdf, it uses the standard rather than the hires
boundingbox for page dimensions
@item
When computing a boundingbox, it adds a small safety margin of 1pt to
the standard boundingbox, except where it would make any boundingbox
coordinate negative.
@end itemize

@node Command-line usage, Notes on PostScript and pdf, Usage, Top
@chapter Command-line usage

epspdf.rb is the backend of epspdftk, but it can also be used
standalone. It shares configuration settings with epspdftk.tcl.

Under Windows, is strongly recommended to invoke epspdf.rb via a wrapper script
epspdf.bat on the search path, e.g.
@example
"@var{path_to_ruby.exe}" "@var{path_to_epspdf.rb}" %*
@end example

The TeX Live package for epspdf already includes wrappers for Windows,
both for epspdf and for epspdftk.

The first parameter of epspdftk is interpreted as startup directory for
the file browser.

From version 0.5.2 on, there is no longer need for a wrapper script under
Unix/Linux/Mac OS X; a symlink on the searchpath to the actual script
suffices.

Basic usage:

@example
epspdf [@var{options}] @var{infile} @var{outfile}
@end example

@menu
* Option summary::
@end menu

@node Option summary,  , Command-line usage, Command-line usage
@section Option summary

Typing  @kbd{epspdf --help} gives you the following summary:
@example
$ epspdf --help
Epspdf version 0.5.2
Copyright (C) 2006, 2008, 2009, 2010 Siep Kroonenberg
Convert between [e]ps and pdf formats
Usage: epspdf.rb [options] infile [outfile]

Default for outfile is file.pdf if infile is file.eps or file.ps
Default for outfile is file.eps if infile is file.pdf

    -g, --gray, --grey               Convert to grayscale;
                                     success not guaranteed
    -G, --GRAY, --GREY               Try harder to convert to grayscale
    -p, --pagenumber=PAGENUMBER      Page to be converted or selected
    -b, --bbox, --BoundingBox        Compute tight boundingbox
    -n, --no-hires                   Don't use hires boundingbox
    -r, --hires                      Use hires boundingbox
    -T, --target=TARGET              Target use of pdf; one of
                                     default, printer, prepress, screen, ebook
    -N, --pdfversion=PDFVERSION      Pdf version to be generated
    -I                               Ignore pdftops even if available
                                     (default: use if available)
    -U                               Use pdftops if available
                                     (overrides previous -I setting)
    -C, --custom=CUSTOMOPTIONS       Custom options for conversion to pdf,
                                     view Use.htm and ps2pdf.htm from
                                     the Ghostscript documentation set
    -P, --psoptions=PSOPTIONS        Options for pdftops; default -level3,
                                     don't include -eps or page number options;
                                     these will be generated by the program
    -i, --info                       Info: display detected filetype
    -s                               Save (some) settings
    -d                               Debug: don't remove temp files
        --gui[=ACTION]               Do not use; reserved for GUI

    -v, --version                    Prints version info
    -h, --help                       Show this message
@end example

@node Notes on PostScript and pdf, Bitmapped graphics for @LaTeX{} and pdflatex, Command-line usage, Top
@chapter Notes on PostScript and pdf

@menu
* Bitmapped and vector::
* Font embedding::
* Eps preview headers::
* Bounding- and other boxes::
* Orientation::
* Exporting PostScript from Windows programs::
@end menu

@node Bitmapped and vector, Font embedding, Notes on PostScript and pdf, Notes on PostScript and pdf
@section Bitmapped and vector

Pictures can be described either in terms of pixels, or more abstractly,
in terms of geometric shapes, fonts and text.

Bitmapped or pixel-based graphics are appropriate for photographs and
screenshots, but less so for diagrams and spreadsheet-generated
graphics.

A file in PostScript- or pdf format can contain both types of graphic
data.

Vector graphics can be freely scaled without losing sharpness or
becoming pixellated.  If bitmapped graphics are enlarged too much,
individual pixels become apparent. With low-resolution bitmaps this
happens sooner than with high-resolution bitmaps, but high-resolution
bitmaps have (much) larger file sizes, and take longer to process.

So avoid converting vector to bitmap. However, converting from bitmap to
vector is also best avoided, since it is very hard to do well.

Epspdf normally avoids conversion from vector to bitmap and never
converts the other way. With the screen- and ebook ``Target use''
option, included bitmaps tend to be downsampled, i.e. reduced to a lower
resolution.

@node Font embedding, Eps preview headers, Bitmapped and vector, Notes on PostScript and pdf
@section Font embedding

When converting to pdf, Ghostscript handles font embedding differently
depending on the ``Target use'' option. For prepress, it embeds even
the standard fonts, including Times etc. Ghostscript has copies of these
fonts in case the PostScript file doesn't have them. For screen, it
doesn't embed standard fonts.

You can embed fonts after the fact by converting pdf to eps or ps, and
back to pdf, with target use set to ``prepress''. However, don't try this
unless you have pdftops.

If target use is set to ``screen'', then standard fonts will be removed
instead of added. This option may also cause downsampling of bitmaps.

@node Eps preview headers, Bounding- and other boxes, Font embedding, Notes on PostScript and pdf
@section Eps preview headers

Preview headers are quietly stripped from eps files. These
preview headers are used by e.g. desktop-publishing software to
represent eps files on screen without having to interpret the
PostScript code itself. Epspdf currently has no option to preserve
or add them.

@node Bounding- and other boxes, Orientation, Eps preview headers, Notes on PostScript and pdf
@section Bounding- and other boxes

A PostScript file may have a page size and a boundingbox defined. A pdf
file may have a mediabox, a trimbox and various other boxes. Ghostscript
by itself normally converts the PostScript page -- which is anchored at
(0,0) -- to the pdf mediabox.

When epspdf or a similar program converts eps to pdf, it adds code to
move the bottom left corner of the graphic to (0,0) and to set the page
to the size of the graphic. Anything outside the boundingbox should be
cut off.

Both Ghostscript and pdftops have some parameters for setting or using
these boxes; consult Ps2pdf.htm from the Ghostscript documentation and
``pdftops --help'' or ``man pdftops''.

@node Orientation, Exporting PostScript from Windows programs, Bounding- and other boxes, Notes on PostScript and pdf
@section Orientation

There appears to be no reliable way to set orientation for PostScript-
and pdf files. This may result part of a graphic being cut off after
conversion or even everything falling outside the page / mediabox /
boundingbox. It may help to change the extension from ``.eps'' to
``.ps'' before converting to pdf. In this case, let epspdf generate a
new boundingbox.

@node Exporting PostScript from Windows programs,  , Orientation, Notes on PostScript and pdf
@section Exporting PostScript from Windows programs

Often, the only way to get EPS or PostScript from a Windows program is
by ``printing'' to a PostScript file. From some programs, you can print
a selection. A suitable driver which comes with Windows is Generic / MS
Publisher Imagesetter. Pay attention to the printer properties: choose
``Outline'' for font downloading and avoid the ``Optimize for speed''
setting for PostScript Output Option. Try e.g. ``Archive''
instead. These options can be found under the Advanced button.

@image{images/ps_settings,2.5in}

Other possibilities are the TpX and wmf2eps programs, which both
have options to write clipboard contents to an emf file. Wmf2eps
uses a printer driver in the background. For faithful conversion,
pick wmf2eps; for subsequent editing, choose TpX. Both programs are
available from @url{http://www.tug.org/ctan.html}.

@node Bitmapped graphics for @LaTeX{} and pdflatex, Troubleshooting, Notes on PostScript and pdf, Top
@chapter Bitmapped graphics for @LaTeX{} and pdflatex

pdflatex can use graphics in .png format (best for screenshots) and .jpg
format (best for photographs) directly. However, for @LaTeX{} you are
stuck with .eps format. Tips for converting to .eps:

@menu
* Linux::
* Mac OS X::
* Windows::
@end menu

@node Linux, Mac OS X, Bitmapped graphics for @LaTeX{} and pdflatex, Bitmapped graphics for @LaTeX{} and pdflatex
@section Linux

@table @emph
@item sam2p
This command-line bitmap-to-PostScript/pdf conversion utility is
available from @url{http://code.google.com/p/sam2p/} and may already be
packaged for your distribution. It produces very small files:
@samp{sam2p image.png image.eps}
@item ImageMagick/convert
@command{convert} from the ImageMagick package is a command-line
utility: @samp{convert image.png image.eps}
@item The GIMP
This is the premier open source image editing program. It is often
pre-installed on Linux, and is also available for other platforms. The
GIMP can save in eps format.
@end table

@node Mac OS X, Windows, Linux, Bitmapped graphics for @LaTeX{} and pdflatex
@section Mac OS X

Mac OS X's built-in Preview application can read most bitmapped formats
and save them as .pdf, which epspdf can convert to .eps.

@node Windows,  , Mac OS X, Bitmapped graphics for @LaTeX{} and pdflatex
@section Windows

Windows is not a particularly friendly environment for PostScript and
pdf. A couple of command-line utilities try to fill the gap, @emph{e.g.}
@example
sam2p image.png image.eps
@end example
or
@example
bmeps -c image.png image.eps
@end example
sam2p is distributed with TeX Live (Windows only), bmeps both with TeX
Live and with MikTeX. Without the @code{-c} option, bmeps produces a
grayscale image. It produces larger files than sam2p.

@menu
* GUI use of sam2p and bmeps::
@end menu

@node GUI use of sam2p and bmeps,  , Windows, Windows
@subsection GUI use of sam2p and bmeps

Create a batchfile @file{bitmap2eps.bat} with contents
@verbatim
sam2p "%~1" "%~dpn1.eps"
@end verbatim
(TeX Live) or
@verbatim
bmeps -c "%~1" "%~dpn1.eps"
@end verbatim
(MikTeX) and place it @emph{e.g.} on your desktop. Now if you drop a
bitmapped graphic on this batchfile then you will get an eps file with
the same name as the original, but with extension @code{.eps}.

You can also right-click on a bitmap, choose @emph{Open With...} and
browse to this file bitmap2eps.bat, resulting in conversion to .eps. The
next time you do this with a file of the same type, bitmap2eps.bat will
already be in the list of possible programs for opening the file.

@node Troubleshooting, Change history, Bitmapped graphics for @LaTeX{} and pdflatex, Top
@chapter Troubleshooting

@menu
* Grayscaling fails::
* Part of the graphic gets cut off::
* Fonts look ugly::
* epspdftk quit unexpectedly (Mac OS X applet)::
* Resources for troubleshooting::
@end menu

@node Grayscaling fails, Part of the graphic gets cut off, Troubleshooting, Troubleshooting
@section Grayscaling fails

See above, under @ref{gray,,Grayscaling}. Epspdf is
limited by what can be done by the backend tools, i.e. Ghostscript
and pdftops. In particular, epspdf cannot grayscale bitmapped data.

@node Part of the graphic gets cut off, Fonts look ugly, Grayscaling fails, Troubleshooting
@section Part of the graphic gets cut off

Things to try:
@itemize @bullet
@item
If the PostScript file was generated with the Windows PostScript driver,
experiment with the PostScript Output option. Don't choose Optimize for
Speed.
@item
Replace the extension with ``.ps'' and let epspdf generate a
boundingbox.
@item
Boundingbox calculations may be slightly inaccurate where text is
involved. If just a sliver is cut off, let epspdf ignore the
high-resolutuion boundingbox. Command-line option: ``-n'' or
``--no-hires''.
@end itemize

@node Fonts look ugly, epspdftk quit unexpectedly (Mac OS X applet), Part of the graphic gets cut off, Troubleshooting
@section Fonts look ugly

If Ghostscript has to do the conversion from pdf to ps then text will
not remain text, but will be replaced by drawn shapes or bitmaps. Try
to get hold of the xpdf suite, which includes pdftops.

@node epspdftk quit unexpectedly (Mac OS X applet), Resources for troubleshooting, Fonts look ugly, Troubleshooting
@section Epspdftk quit unexpectedly (Mac OS X applet)

This sometimes happens to me when I start epspdftk from the AppleScript
applet. Unfortunately, I have no idea where this comes from.

Try the ``Reopen'' button in the popup dialog. If this repeatedly fails,
install the regular Unix edition instead and run it from the
command-line.

@node Resources for troubleshooting,  , epspdftk quit unexpectedly (Mac OS X applet), Troubleshooting
@section Resources for troubleshooting

@i{Logfile.} The GUI has a button for viewing log output. This same
output is also written to a file @file{epspdf.log}. For Linux/Unix/Mac
OS X this is in a subdirectory .epspdf of your home directory; for
Windows it is in a subdirectory epspdf of @file{%APPDATA%}. This APPDATA
directory may be @file{c:\Documents and Settings\@var{your user
name}\Application Data} or @file{c:\Users\@var{your user
name}\AppData\Roaming}. Otherwise, open a command prompt and type
@kbd{echo %APPDATA%}, which will produce this information.

The logfile lists all epspdf calls and all Ghostscript- and pdftops
calls plus error information. ``EPCallError'' is probably a program
error. 'EPSystemError'' is more likely caused by a faulty file, but may
be a program error as well.

@i{Temporary files.} The temporary files may give clues as
well. Uncheck the button ``Remove temp files'', or for the
command-line version, give a -d parameter to keep the temporary
files. Check the log(file) as to which temporary files have been
created.

@anchor{Documentation}@i{Ghostscript- and pdftops documentation.} For
Ghostscript, the most important files are Ps2pdf.htm and Use.htm. For
pdftops, type @kbd{pdftops -h}. For Unix, there is also a man page, and
for Windows there is a file pdftops.txt in the distribution zip.

@node Change history,  , Troubleshooting, Top
@chapter Change history

@menu
* Version 0.5::
* Version 0.4::
@end menu

@node Version 0.5, Version 0.4, Change history, Change history
@section Version 0.5

The GUI has been rewritten in Tcl/Tk, removing the dependence on the
Ruby/Tk interface library.

The Windows installer now installs a small Ruby subset and the standard
epspdf distribution, but with epspdftk.tcl replaced with a starpack: a
single executable containing @file{epspdftk.tcl} and a Tcl/Tk
runtime. See @url{http://wiki.tcl.tk/52}.

Epspdf now uses its own subdirectory for both the logfile and the
configuration file. For Linux/Unix/Mac OS X this is
@file{$HOME/.epspdf}, for Windows it is @file{%APPDATA%\epspdf}.
On all supported platforms, settings are stored in the file
@file{config} in this directory. Under Windows, the registry is no
longer used for this.

A button has been added to view log output.

There is a second new button ``Remove temp files'', which is normally
checked, causing temporary files to be deleted after each
conversion. Unchecking this button may be useful for troubleshooting. In
previous versions, temporary files were deleted at the end of the entire
epspdftk session but that has become less practical now that the GUI and
epspdf itself have become two separate programs.

The ``Open with...'' option for Windows has been dropped for technical
reasons.

The ``--version'' option now prints the version string instead of
setting the desired pdf version.

The ``--info'' option now also prints the number of pages for pdf
files.

@node Version 0.4,  , Version 0.5, Change history
@section Version 0.4

Hi-res boundingboxes are now supported. By default, conversion from eps
to pdf now uses the hires boundingbox as ``page'' to determine the page
dimensions of the pdf file. Other conversions preserve or generate a
hires boundingbox.

Under Windows, the new version looks for an installed @TeX{} and will
use its private Ghostscript if it cannot find a separately installed
Ghostscript. @TeX{} Live's pdftops, being on the searchpath, will be
used unless epspdf finds another copy first.

There is now a ``-v'' (lowercase) option to print the version string.

@ifhtml
@section @url{index.html,Main page}
@end ifhtml

@bye