home *** CD-ROM | disk | FTP | other *** search
- xpdf
- ====
- and: pdftops, pdftotext
-
- version 0.7a (beta)
- 98-feb-22
-
- The xpdf, pdftops, and pdftotext software and documentation are
- copyright 1996-1998 Derek B. Noonburg.
-
- Email: derekn@aimnet.com
- WWW: http://www.aimnet.com/~derekn/xpdf/
-
- The PDF data structures, operators, and specification are
- copyright 1995 Adobe Systems Inc.
-
-
- What is xpdf?
- -------------
-
- Xpdf is a viewer for Portable Document Format (PDF) files. (These are
- also sometimes also called 'Acrobat' files, from the name of Adobe's
- PDF software.) Xpdf runs under the X Window System on UNIX, VMS, and
- OS/2.
-
- Xpdf is designed to be small and efficient. It does not use the Motif
- or Xt libraries. It uses standard X fonts. Xpdf is quite usable on a
- 486-66 PC running Linux.
-
-
- Compatibility
- -------------
-
- Xpdf is developed and tested on a Linux 2.0 x86 system.
-
- In addition, it has been compiled by others on Solaris, AIX, HP-UX,
- SCO UnixWare, Digital Unix, Irix, and numerous other Unix
- implementations, as well as VMS, and OS/2. It should work on pretty
- much any system which runs X11 and has Unix-like libraries. You'll
- need ANSI C++ and C compilers to compile it.
-
- If you compiled xpdf for a system not listed on the web page, please
- let me know. If you're willing to make your binary available by ftp
- or on the web, I'll be happy to add a link from the xpdf web page. I
- have decided not to host any binaries I didn't compile myself (for
- disk space and support reasons).
-
- If you can't get xpdf to compile on your system, send me email and
- I'll try to help.
-
- Ports of xpdf to the Acorn and Amiga have been made. See the xpdf web
- page for links.
-
-
- Getting xpdf
- ------------
-
- The latest version is available from:
-
- http://www.aimnet.com/~derekn/xpdf/
-
- or:
-
- ftp://ftp.aimnet.com/pub/users/derekn/xpdf/
-
- Source code and several precompiled executables are available.
-
- Announcements of new versions are posted to several newsgroups
- (comp.text.pdf, comp.os.linux.announce, and others) and emailed to a
- list of people. If you'd like to receive email notification of new
- versions, just let me know.
-
-
- Running xpdf
- ------------
-
- To run xpdf, simply type:
-
- xpdf file.pdf
-
- To generate a PostScript file, hit the "print" button in xpdf, or run
- pdftops:
-
- pdftops file.pdf
-
- To generate a plain text file, run pdftotext:
-
- pdftotext file.pdf
-
- Command line options and many other details are described in the man
- pages (xpdf.1, pdftops.1, and pdftotext.1) and the VMS help files
- (xpdf.hlp, pdftops.hlp, and pdftotext.hlp).
-
-
- Fonts
- -----
-
- Xpdf uses X server fonts. It requires the following fonts:
-
- * Courier: medium-r, bold-r, medium-o, and bold-o
- * Helvetica: medium-r, bold-r, medium-o, and bold-o
- * Times: medium-r, bold-r, medium-i, and bold-i
- * Symbol: medium-r
- * Zapf Dingbats: medium-r
-
- Most X installations should already have all of these fonts, except
- Zapf Dingbats. You can install a Type 1 Zapf Dingbats font -- see the
- mkfontdir(1) man page for details. Use this font descriptor in your
- fonts.scale file:
-
- -itc-zapfdingbats-medium-r-normal--0-0-0-0-p-0-adobe-fontspecific
-
- You can get a Type 1 font file from the ghostscript 4.x distribution
- (look for d050000l.pfb).
-
- X servers, starting at R5, support font scaling. Xpdf will
- automatically take advantage of this. There are two types of scaling.
- The first type uses standard bitmap fonts: if a font doesn't exist in
- the requested size, the server will scale the bitmapped characters.
- This is reasonably fast, and the results are readable but not very
- pretty. X servers can also handle true scalable, e.g., Type 1, fonts.
- (See the mkfontdir(1) man page for details on setting these up.)
- Scalable fonts are slower, especially since PDF documents tend to use
- lots of fonts, but they look much nicer.
-
- Some X servers also support font rotation. Xpdf will use this feature
- if available.
-
-
- The Unisys LZW Patent
- ---------------------
-
- Nearly all PDF files include data which has been compressed with the
- LZW compression algorithm. Unfortunately, LZW is covered by a
- software patent which is owned by Unisys Corporation. Unisys refuses
- to license this patent for PDF-related use in software such as xpdf
- which is released for free and which may be freely redistributed.
- (This is same algorithm which is used by GIF. However, Unisys is not
- doing licensing for free PDF viwers in the same way as for free GIF
- viewers.)
-
- As a workaround, xpdf converts PDF-format LZW data to compress-format
- LZW data. (The standard UNIX compress utility also uses LZW, but with
- a slightly different file format.) This conversion does *not*
- decompress the data; it simply converts it to a different file format.
- Xpdf then calls uncompress to actually decompress the data.
-
- I have been told by several notable people that the LZW patent covers
- compression only, and does not cover decompression. This seems pretty
- fuzzy to me, so I'm going to stick with my workaround, at least for
- now.
-
- For Unisys's slant on things (mostly regarding GIF), see
- <http://www.unisys.com/LeadStory/lzwterms.html> and
- <http://www.unisys.com/LeadStory/lzwfaq.html>. These pages mention
- an email address for feedback.
-
-
- Compiling xpdf
- --------------
-
- Xpdf is written in C++ (with a little bit of C). It should work with
- any ANSI-compliant C++ and C compilers. The systems and compilers
- it's been tested with are listed on the xpdf web page.
-
- *** To compile xpdf for UNIX:
-
- * Run the configure script:
-
- ./configure
-
- This should produce a set of makefiles customized for your system.
- The configure script accepts the following options (in addition to
- the usual things accepted by autoconf configure scripts):
-
- --enable-a4-paper
- Switches the paper size for PostScript output (xpdf and
- pdftops) to A4. The default is Letter size.
-
- --enable-no-text-select
- With this option, xpdf will not copy text. (This is only
- useful on closed systems where the user can't get at the PDF
- file directly.)
-
- --with-gzip
- Use gzip instead of uncompress.
-
- * Type 'make'. This should build the executables:
-
- xpdf/xpdf
- pdftops/pdftops
- pdftotext/pdftotext
-
- You can also do 'make xpdf', etc., to compile just one of the
- executables.
-
- * If desired, type 'make install' to install the binaries and man
- pages.
-
- If the configure script doesn't work for some reason, the old
- Makefile.config and Makefiles are included (as Makefile.config.old,
- Makefile.old, and */Makefile.old). But please let me
- (derekn@aimnet.com) know what went wrong, as I don't intend to support
- Makefile.config anymore.
-
- *** To compile xpdf for OS/2:
-
- Xpdf is known to run under OS/2 with the EMX runtime environment and
- XFree86. The configure script has not been tested on OS/2, however.
-
- *** To compile xpdf for VMS:
-
- * There are two sets of scripts: vmscomp.com (for gcc on VAX) and
- vmsdecccomp.com (for DEC C on Alpha). There are four of each: in
- the top-level directory, [.goo], [.ltk], and [.xpdf]. You may need
- to edit these scripts as appropriate for your system.
-
- * The 'stddef.h' include file which comes with older versions of gcc
- may be missing a definition for wchar_t. In this case, add the
- following lines:
- -----
- File GNU_CC:[INCLUDE]STDDEF.H;2
- 44 /* Wide characters, not yet supported by VAXCRTL [match VAXC's <stddef.
- 45 #if !defined(_WCHAR_T) && !defined(_WCHAR_T_)
- 46 typedef unsigned int wchar_t;
- 47 #endif
- 48 #define _WCHAR_T
- 49 #define _WCHAR_T_
- 50
- -----
-
- * Type '@vmscomp' or '@vmsdecccomp' in the top-level directory.
-
- * The executables will be left in '[.xpdf]xpdf' and '[.xpdf]pdftops'.
-
-
- Distribution
- ------------
-
- Xpdf may be distributed under the following conditions:
-
- 1. This file ('README') is included, unmodified, in the distribution.
-
- 2. The distribution includes:
- a. all of the xpdf source code and documentation, unmodified; OR
- b. one or more xpdf executables, compiled from the unmodified
- source code, plus the associated documentation (UNIX man pages
- or VMS help files); OR
- c. both of the above.
-
- If you distribute xpdf, I would appreciate receiving a pointer (ftp
- site, BBS phone number, etc.) or a copy (disk, CD-ROM, etc.).
-
- Modified versions of xpdf or applications using some or all of the
- xpdf code (i.e., 'derivative works' under copyright law) may not be
- distributed without explicit permission.
-
-
- Bugs
- ----
-
- This is a beta release of xpdf, and there are still a bunch of PDF
- features which I have yet to implement.
-
- At this point, the biggest problem is that embedded fonts are not
- handled correctly.
-
- If you find a bug in xpdf, i.e., if it prints an error message,
- crashes, or incorrectly displays a document, and you don't see that
- bug listed here, please send me email, with a pointer (URL, ftp site,
- etc.) to the PDF file.
-
-
- Acknowledgments
- ---------------
-
- Thanks to:
-
- * Patrick Voigt for help with the remote server code.
- * Patrick Moreau for the VMS port.
- * David Boldt and Rick Rodgers for sample man pages.
- * Brendan Miller for the icon idea.
- * Olly Betts for help testing pdftotext.
- * Peter Ganten for the OS/2 port.
- * Michael Richmond for the Win32 port of pdftops and pdftotext.
-
-
- References
- ----------
-
- Adobe Systems Inc., _Portable Document Format Reference Manual_.
- Addison-Wesley, 1993, ISBN 0-201-62628-4.
- [The printed manual for PDF version 1.0.]
-
- Adobe Systems Inc., _Portable Document Format Reference Manual_,
- Version 1.2. November 12, 1996.
- [Updated manual for PDF 1.2. Also includes the encryption spec.
- Available on the WWW as
- http://www.adobe.com/supportservice/devrelations/PDFS/TN/PDFSPEC.PDF .]
-
- Adobe Systems Inc., _PostScript Language Reference Manual_, 2nd ed.
- Addison-Wesley, 1990, ISBN 0-201-18127-4.
- [The official PostScript manual.]
-
- Adobe Systems Inc., _Supporting the DCT Filters in PostScript Level
- 2_, Adobe Developer Support Technical Note #5116. 1992.
- [Description of the DCTDecode filter parameters.]
-
- Anonymous, RC4 source code.
- [This is the algorithm used to encrypt PDF files. Available on
- various ftp sites, e.g., ftp://ftp.ox.ac.uk/pub/crypto/misc/rc4.tar.gz
- or ftp://idea.sec.dsi.unimi.it/pub/crypt/code/rc4.tar.gz .]
-
- CCITT, _Blue Book_, Volume VII Fascicle 3: "Terminal Equipment and
- Protocols for Telematic Services", Recommendations T.4 and T.6.
- [The official Group 3 and 4 fax standards. These are available on the
- net (but misformatted) as
- ftp://ftp.uu.net/doc/standards/ccitt/1988/7_3_01.ps and 7_3_02.ps .]
-
- L. Peter Deutsch, "ZLIB Compressed Data Format Specification version
- 3.3". RFC 1950.
- [Information on the general format used in FlateDecode streams.]
-
- L. Peter Deutsch, "DEFLATE Compressed Data Format Specification
- version 1.3". RFC 1951.
- [The definition of the compression algorithm used in FlateDecode
- streams.]
-
- Jim Flowers, "X Logical Font Description Conventions", Version 1.5, X
- Consortium Standard, X Version 11, Release 6.1.
- [The official specification of X font descriptors, including font
- transformation matrices. Available on the net as
- ftp://ftp.x.org/pub/R6.1/xc/doc/hardcopy/XLFD/xlfd.PS.Z .]
-
- Foley, van Dam, Feiner, and Hughes, _Computer Graphics: Principles and
- Practice_, 2nd ed. Addison-Wesley, 1990, ISBN 0-201-12110-7.
- [Colorspace conversion functions, Bezier spline math.]
-
- Robert L. Hummel, _Programmer's Technical Reference: Data and Fax
- Communications_. Ziff-Davis Press, 1993, ISBN 1-56276-077-7.
- [CCITT Group 3 and 4 fax decoding.]
-
- Christoph Loeffler, Adriaan Ligtenberg, George S. Moschytz, "Practical
- Fast 1-D DCT Algorithms with 11 Multiplications". IEEE Intl. Conf. on
- Acoustics, Speech & Signal Processing, 1989, 988-991.
- [The fast IDCT algorithm used in the DCTDecode filter.]
-
- R. Rivest, "The MD5 Message-Digest Algorithm". RFC 1321.
- [MD5 is used in PDF document encryption.]
-
- Gregory K. Wallace, "The JPEG Still Picture Compression Standard".
- [Good description of the JPEG standard. Available on the net as
- ftp://ftp.uu.net/graphics/jpeg/wallace.ps.gz . Also published in
- CACM, April 1991, and submitted to IEEE Transactions on Consumer
- Electronics.]
-
- "ISO 8859-2 (Latin 2) Resources".
- [This is a web page with all sorts of useful Latin-2 character set and
- font information:
- http://sizif.mf.uni-lj.si/linux/cee/iso8859-2.html .]
-