com.lowagie.text.pdf.fonts.cmap_info.txt Maven / Gradle / Ivy
The *.cmap and *.properties files in this jar are necessary
to produce PDF files with iText that use CJK fonts.
Note that whatever value you pass for the 'embedded' parameter
with the method BaseFont.createFont, the font WILL NOT BE embedded.
To understand why, please read the following information.
The fonts that are used in Acrobat Reader when viewing a PDF file
that uses CJK fonts will be downloaded in one or more font packs.
You can download these fontpacks yourself from this URL:
http://www.adobe.com/products/acrobat/acrrasianfontpack.html
On this page, you can find the following information:
"If the author of an Adobe (R) Portable Document Format (PDF) file
embeds CJK and Central European (CE) fonts in a PDF document, then
any language version of Adobe Reader (R) software will be able to
display the CJK and CE text on any system without additional software.
If the author of the PDF document uses CJK or CE fonts but does not
embed them in the document, then the correct fonts will need to be
installed in order to view the Adobe PDF file on non-native systems."
When you download one of the font packs, for instance the font
pack for "Chinese Simplified", you will see that the fonts are
licensed for use in Adobe Reader only:
"Note: The font software contained in this package is being licensed
to you solely for use with Adobe (R) Acrobat (R) Reader (R) software
("Acrobat Reader") and is subject to the terms and conditions of
the electronic End-User License Agreement accompanying Acrobat Reader."
This explains why iText doesn't ever embed a CJK font in the PDF file.
These fonts have to be downloaded and used in the context of Adobe
Reader; you can not use them with iText to produce a PDF document
that has these fonts embedded (as you would do with other fonts) so
that they can be viewed in other readers; unless you have a license
from Adobe to use these fonts.
The *.cmap and *.properties files in this jar, do not contain
any font program. They contain information (mappings, metrics,...)
that is based on font information distributed on Adobe's site:
http://partners.adobe.com/public/developer/acrobat/index_advanced.html#pci
The original copyright notice of the mappings is as follows:
"Copyright 1990-2000 Adobe Systems Incorporated.
All Rights Reserved.
Patents Pending
NOTICE: All information contained herein is the property
of Adobe Systems Incorporated.
Permission is granted for redistribution of this file
provided this copyright notice is maintained intact and
that the contents of this file are not altered in any
way from its original form.
PostScript and Display PostScript are trademarks of
Adobe Systems Incorporated which may be registered in
certain jurisdictions."
The original files with the mappings are plain text files,
and therefore not optimized for being read by a computer
software program. That's why they were pre-processed to map
directly the Unicode value with the CID value using a 64k
char array. No data was changed in this process.
Additionally, the iTextAsian.jar contains some properties files
with font metrics. These are included for the same reason AFM
files are needed (see also the file mustRead.html shipped with
the iText.jar). As defined in the PDF reference: "The width
information for each glyph is stored both in the font dictionary
and in the font program itself. (The two sets of widths must be
identical; storing this information in the font dictionary, although
redundant, enables a consumer application to determine glyph
positioning without having to look inside the font program.)"
See PDF Reference sixth edition section 5.1.3 (p393-394).
Whereas in the case of CJK fonts, the font program is subject
to the Adobe Reader EULA, the font metrics aren't. Page 396:
"Glyph metric information is also available separately in the
form of Adobe font metrics (AFM) and Adobe composite font metrics
(ACFM) files. These files are for use by application programs
that generate PDF page descriptions and must make formatting
decisions based on the widths and other metrics of glyphs. (...)
Specifications for the AFM and ACFM file formats are available
in Adobe Technical Note #5004, Adobe Font Metrics File Format
Specification; the files can be obtained from the Adobe Solutions
Network Web site."
Unfortuntately the URL of these files has changed over time, and
some metrics files seem to have been removed. However, you'll
find sufficient information in the Technical Notes to build your
own AFM and/or ACFM files if you ever need font metrics in the
Adobe Font Metrics format.
Note that the properties files in the iTextAsian.jar contain
font metrics, but they are not stored in the AFM or ACFM format.
For reasons of performance, the font metrics were stored as
key-value pairs. Compare the keys in the properties files with
the keys mentioned in Table 5.19 on p456 of the PDF Reference.
This way, the necessary key-value pairs can be imported directly
into a Font Dictionary that is part of a PDF file created by iText.
These specific metrics files were created by Paulo Soares and
may be used, copied, and distributed for any purpose and without
charge, with or without modification.